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Office of Scientific and Technical Information
Does the Air-Conditioning Engineering Rubric Work in Residences...
NLE Websites -- All DOE Office Websites (Extended Search)
Does the Air-Conditioning Engineering Rubric Work in Residences? Title Does the Air-Conditioning Engineering Rubric Work in Residences? Publication Type Conference Paper LBNL...
Gas Powered Air Conditioning Absorption vs. Engine-Drive
E-Print Network (OSTI)
It used to be that the only alternative to costly electric air conditioning was the double-effect gas-fired absorption chiller/heaters. Beginning in the 1980's, they were the "star" equipment promoted by gas companies throughout the nation. Although not a new technology at the time, neither was the gas engine. But now in the 19901s, gas engine-drive (GED) chillers have "hit" the air conditioning market with a "bang". In the Lone Star Gas Company area in 1995, GED chillers are now being considered in as many projects as are Absorption. units. Where once the only studies being analyzed were absorption vs. electric chiller operation costs. Now, the choice is: Why, Where, and How to choose between gas fired Absorption and GED chillers. WHY Absorption or Engine ? . Absorption uses the most environmentally friendly refrigerant - water. . Absorption chillers are chiller/heaters Absorption chillers are manufactured by the four US major manufacturers Absorption chillers have few moving parts . Engine chillers provide "free" hot water Engine chillers retrofit with DX systems . Engine chillers use less gas per ton WHERE Do Absorption And Engine Chillers Belong? . Absorption: Office buildings, restaurants, industries, churches, universities . Engine: Hospitals, universities, hotels, apartments, industries HOW To Choose Between Absorption And Engine Chillers? Energy cost Operation and maintenance costs Equipment cost Environmental concerns Thermal requirements . Space requirements Staff experience
Phillips, J. N.
Seawater Air Conditioning for Downtown Engineering Project Manager
of energy use in typical office and hotel buildings in Hawaii. Hawaii relies on imported fossil fuels electricity usage by 75 percent compared to conventional air conditioning systems. This renewable energy conditioning. Conventional air conditioning systems are energy intensive and represent close to 50 percent
Frandsen, Jannette B.
Air Conditioning and lungs
Air Conditioning and lungs Name: freeman Status: NA Age: NA Location: NA Country: NA Date: Around 1993 Question: What affect does air conditioning have upon the lungs of the...
Large HVAC Codes and Standards Update 2000: American Society of Heating, Refrigerating and Air-Conditioning Engineers
Science Conference Proceedings (OSTI)
This report documents EPRI activities in the year 2000 related to building codes and standards. The following activities are covered: attendance at the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) meetings and participation in technical committee and subcommittee meetings related to ASHRAE Standard 90.l; review of relevant U.S Department of Energy (DOE) appliance standards; review of developments of other building energy code organizations; and participation in the E...
Movements in air conditioning.
??Movements in Air Conditioning is a collection of poems that explores the obstacles inherent in creating a new sense of home in a country that� (more)
Hitt, Robert D. (Robert David)
Comparison of Zone Cooling Load for Radiant and All-Air Conditioning Systems
Load for Radiant and Air Conditioning Systems. ProceedingsRefrigerating and Air Conditioning Engineers Inc. Babiak,of European Heating ahd Air-Conditioning Associations. CEN (
Feng, Jingjuan; Schiavon, Stefano; Bauman, Fred
Solar air conditioning
DOE Green Energy (OSTI)
Development of a hybrid solar-assisted air conditioning system that combines a vapor compression section for sensible cooling with a desiccant section for dehumidification and that uses both solar energy and condenser waste heat to drive the dehumidifier has been under way for the last two years (1981 and 1982). The results of this research are included in this report: utilizing solar energy in an economical way has proven quite difficult.
Robison, H.
Air Conditioning | Department of Energy
Energy.gov (U.S. Department of Energy (DOE)) Indexed Site
Conditioning Conditioning Air Conditioning July 1, 2012 - 6:28pm Addthis Air conditioners cost U.S. homeowners more than $11 billion each year, and regular maintenance can keep your air conditioner running efficiently. | Photo courtesy of ©iStockphoto/JaniceRichard Air conditioners cost U.S. homeowners more than $11 billion each year, and regular maintenance can keep your air conditioner running efficiently. | Photo courtesy of ©iStockphoto/JaniceRichard How does it work? An air conditioner uses energy -- usually electricity -- to transfer heat from the interior of your home to the relatively warm outside environment. Two-thirds of all homes in the United States have air conditioners. Air conditioners use about 5% of all the electricity produced in the United States, at an annual cost of more than $11 billion to homeowners. As a
Optimization of Air Conditioning Cycling.
??Systems based on the vapor compression cycle are the most widely used in a variety of air conditioning applications. Despite the vast growth of modern� (more)
Seshadri, Swarooph
Computer controlled air conditioning systems
SciTech Connect
This patent describes an improvement in a computer controlled air conditioning system providing for circulation of air through an air conditioned house in contact with concrete walls requiring a humidity within a critical range. The improvement consists of: a computer for processing sensed environmental input data including humidity and oxygen to produce output control signals for affecting the humidity of the air in the house; provision for an air flow circulation path through the house in contact with the concrete walls; sensing responsive to the amount of oxygen in the house for providing input signals to the computer; mixing for combining with the air in the house a variable amount of fresh atmospheric air to supply fresh oxygen; and humidity modifying means for modifying the humidity of the air flowing in the flow path responsive to the control signals.
Dumbeck, R.F.
Air conditioning: Impact on the built environment
The topics discussed in this book are: Introduction. 1. Air Conditioning - An Ever Expanding Market. 2. Building Envelope Design and Air Contitioning. 3. Air Conditioning and Energy - The CIBSE Building Energy Code. 4. Thermal Storage in Air Conditioning Systems. 5. Good Practice in the Design and Construction of Air Conditioning Systems. 6. Software for Air Conditioning Load Analysis and Design. 7. Lloyd's of London - The Architecture of Air Conditioning - Prediction of the Environment.
Sherratt, A.F.C.
Automobile air-conditioning unit. Final report
In this study the refrigerant in the automobile air-conditioner is compressed by thermal energy in a unique compression system rather than by work in a standard compressor. The compression uses an intermittent compression process with a solid absorbent. The vapor is absorbed by an absorbent at relatively low temperature and ejected as the absorbent temperature is raised. A set of one way valves limits flow to one direction. Major contributions are heat transfer requirements, molecular sieve-refrigerant matching, minimizing non-producing mass, solving thermal fatigue and shock problems, and applying this to automobile air-conditioning. The performance study shows energy savings up to fifty percent are possible, depending on engine load. A twenty percent energy savings with the vehicle tested with the air-conditioner in operation is average. The study also showed that less fuel is used with the windows open than with the air-conditioner operating.
Schaetzle, W.J.
Opportunities for Saving Energy and Improving Air Quality in Urban Heat Islands
Refrigeration, and Air conditioning Engineers, Atlanta,Refrigeration, and Air Conditioning Engineers, Atlanta,Refrigeration, and Air Conditioning Engineers, Atlanta,
Akbari, Hashem
Central Air Conditioning | Department of Energy
Central Air Conditioning Central Air Conditioning Central Air Conditioning May 30, 2012 - 8:01pm Addthis Central air conditioners circulate cool air through a system of supply and return ducts. | Photo courtesy of ©iStockphoto/DonNichols. Central air conditioners circulate cool air through a system of supply and return ducts. | Photo courtesy of ©iStockphoto/DonNichols. What does this mean for me? Central air conditioning systems are thermostatically controlled and convenient to use. Central air conditioning systems must be installed properly to operate efficiently. Central air conditioning systems can share ductwork with your heating system. Central air conditioners circulate cool air through a system of supply and return ducts. Supply ducts and registers (i.e., openings in the walls,
Air-Conditioning Basics | Department of Energy
Air-Conditioning Basics Air-Conditioning Basics Air-Conditioning Basics August 16, 2013 - 1:59pm Addthis Air conditioning is one of the most common ways to cool homes and buildings. How Air Conditioners Work Air conditioners employ the same operating principles and basic components as refrigerators. Refrigerators use energy (usually electricity) to transfer heat from the cool interior of the refrigerator to the relatively warm surroundings; likewise, an air conditioner uses energy to transfer heat from the interior space to the relatively warm outside environment. An air conditioner uses a cold indoor coil called the evaporator. The condenser, a hot outdoor coil, releases the collected heat outside. The evaporator and condenser coils are serpentine tubing surrounded by aluminum fins. This tubing is usually made of copper.
environment. An air conditioner uses a cold indoor coil called the evaporator. The condenser, a hot outdoor coil, releases the collected heat outside. The evaporator and...
Investigation of residential central air conditioning load shapes in NEMS
of Residential Central Air Conditioning Load Shapes in NEMSof Residential Central Air Conditioning Load Shapes in NEMSof Residential Central Air Conditioning Load Shapes in NEMS
Hamachi LaCommare, Kristina; Marnay, Chris; Gumerman, Etan; Chan, Peter; Rosenquist, Greg; Osborn, Julie
Heating, Ventilation and Air Conditioning Efficiency
Presented By: WALTER E. JOHNSTON, PE Presented By: WALTER E. JOHNSTON, PE CEM, CEA, CLEP, CDSM, CPE Air Conditioning (HVAC) system is to provide and maintain a comfortable environment within a building for the occupants or for the process being conducted Many HVAC systems were not designed with energy efficiency as one of the design factors 3 Air Air is the major conductor of heat. Lack of heat = air conditioning OR 4 Btu - Amount of heat required to raise one pound of water 1 F = 0.252 KgCal 1 Pound of Water = About 1 Pint of Water ~ 1 Large Glass 1 Kitchen Match Basics of Air Conditioning = 1 Btu 5 = 6 Low Cost Cooling Unit 7 8 Typical Design Conditions 75 degrees F temperature 50% relative humidity 30 - 50 FPM air movement
Lab Breakthrough: Desiccant Enhanced Evaporative Air Conditioning |
Desiccant Enhanced Evaporative Air Conditioning Desiccant Enhanced Evaporative Air Conditioning Lab Breakthrough: Desiccant Enhanced Evaporative Air Conditioning May 29, 2012 - 5:22pm Addthis This breakthrough combines desiccant materials, which remove moisture from the air using heat, and advanced evaporative technologies to develop a cooling unit that uses 90 percent less electricity and up to 80 percent less total energy than traditional air conditioning. This solution, called the desiccant enhanced evaporative air conditioner (DEVAP), also controls humidity more effectively to improve the comfort of people in buildings. View the entire Lab Breakthrough playlist. What are the key facts? Recent materials advances and liquid desiccant advances to design the compact and cost-effective DEVAP system. DEVAP uses 90 percent less electricity and up to 80 percent less
Lab Breakthrough: Desiccant Enhanced Evaporative Air Conditioning Lab Breakthrough: Desiccant Enhanced Evaporative Air Conditioning Lab Breakthrough: Desiccant Enhanced Evaporative Air Conditioning May 29, 2012 - 5:22pm Addthis This breakthrough combines desiccant materials, which remove moisture from the air using heat, and advanced evaporative technologies to develop a cooling unit that uses 90 percent less electricity and up to 80 percent less total energy than traditional air conditioning. This solution, called the desiccant enhanced evaporative air conditioner (DEVAP), also controls humidity more effectively to improve the comfort of people in buildings. View the entire Lab Breakthrough playlist. What are the key facts? Recent materials advances and liquid desiccant advances to design the compact and cost-effective DEVAP system.
Zoned heating and air conditioning system
This patent describes a zoned heating and air conditioning system comprising: a central air handling system with an air heating means and an air cooling means and a blower connected to an air duct system; thermostats each have heating and cooling set points, respectively associated with and located in different zones of a building; dampers respectively associated with each building zone positioned in the air duct system. Each damper has an open position allowing air into the respective zone from the duct system and a closed position; relay means for connecting one thermostat to the air handling system upon a call for heating or cooling by one thermostat and disconnecting all other thermostats by connecting one thermostat's connections between the thermostat and air handling system. Only one thermostat is connected to the air handling system at a time and the relay means disconnects one thermostat from the air handling system after one thermostat is satisified; and damper actuating means for unlocking each damper in one building zone responsive actuated by a respective zone thermostat connected to the air handling system by the relay means. The damper actuates means including a damper solenoid for each damper located adjacent each damper and connected to a respective zone thermostat. It unlocks each damper in one building zone responsive to being actuated by the respective zone thermostat and unlocks the dampers in one building zone when one thermostat is actuated while preventing the dampers in another thermostat's building zone from unlocking.
Beachboard, S.A.
Troubleshooting the residential air conditioning system
In order to effectively diagnose problems in a residential air conditioning system, the technician should develop and follow a logical step-by-step troubleshooting procedure. A list of problems, along with possible causes and solutions, that a technician may encounter when servicing a residential air conditioner is presented.
Puzio, H. [Sussex County Vocational Technical School, Sparta, NJ (United States)
Performance of underfloor air distribution: Results of a field study
Refrigerating, and Air Conditioning Engineers. AtlantaRefrigerating, and Air Conditioning Engineers. AtlantaRefrigerating, and Air-Conditioning Engineers, Inc. ,
Fisk, William; Faulkner, David; Sullivan, Douglas
Heating, ventilation and air conditioning systems
A study is made of several outstanding issues concerning the commercial development of environmental control systems for electric vehicles (EVs). Engineering design constraints such as federal regulations and consumer requirements are first identified. Next, heating and cooling loads in a sample automobile are calculated using a computer model available from the literature. The heating and cooling loads are then used as a basis for estimating the electrical consumption that is to be expected for heat pumps installed in EVs. The heat pump performance is evaluated using an automobile heat pump computer model which has been developed recently at Oak Ridge National Laboratory (ORNL). The heat pump design used as input to the model consists of typical finned-tube heat exchangers and a hermetic compressor driven by a variable-speed brushless dc motor. The simulations suggest that to attain reasonable system efficiencies, the interior heat exchangers that are currently installed as automobile air conditioning will need to be enlarged. Regarding the thermal envelope of the automobile itself, calculations are made which show that considerable energy savings will result if steps are taken to reduce {open_quote}hot soak{close_quote} temperatures and if the outdoor air ventilation rate is well controlled. When these changes are made, heating and cooling should consume less than 10% of the total stored electrical energy for steady driving in most U.S. climates. However, this result depends strongly upon the type of driving: The fraction of total power for heating and cooling ({open_quote}range penalty{close_quote}) increases sharply for driving scenarios having low average propulsion power, such as stop-and-go driving.
Kyle, D.M. [Oak Ridge National Lab., TN (United States); Sullivan, R.A. [Dept. of Energy, Washington, DC (United States)
A study of membrane properties on air conditioning performance.
??Energy consumption due to heating, ventilation, and air conditioning amounts to 10-20% of global electrical energy usage. Air conditioning alone uses one trillion kilowatt hours� (more)
Boyer, Elizabeth J.
Stirling engine with air working fluid
DOE Patents (OSTI)
A Stirling engine capable of utilizing air as a working fluid which includes a compact heat exchange module which includes heating tube units, regenerator and cooler positioned about the combustion chamber. This arrangement has the purpose and effect of allowing the construction of an efficient, high-speed, high power-density engine without the use of difficult to seal light gases as working fluids.
Corey, John A. (North Troy, NY)
Rotating heat pipe for air-conditioning
A unique rotary hermetic heat pipe is disclosed for transferring heat from an external source to an external heat sink. The heat pipe has a tapered condensing surface which is curved preferably to provide uniform pumping acceleration, the heat pipe being rotated at a velocity such that the component of centrifugal acceleration in an axial direction parallel to the tapered surface is greater than lG and so that the condensing surface is kept relatively free of liquid at any attitude. The heat pipe may be incorporated in an air conditioning apparatus so that it projects through a small wall opening. In the preferred air conditioning apparatus, a hollow hermetic air impeller is provided which contains a liquefied gaseous refrigerant, such as freon, and means are provided for compressing the refrigerant in the evaporator region of the heat pipe.
Gray, V.H.
Importance of Design Conditions for Sizing Air-Conditioning Plant
Design conditions based on the meteorological data collected at two weather stations located less than 10 km away from each other within Kuwait City are presented for dry-bulb temperature (DBT) and web-bulb temperature (WBT) prioritization. The proposed design conditions specific to the location and the application are drastically different than currently used single design conditions for all application and locations. Cooling load estimates fro two building located in Kuwait have been analyzed for the proposed and the current design conditions to highlight over- or under-sizing the air-conditioning (A/C) plant capacity. Finally, a number of recommendations are made for architects and designers to use proper design conditions to ensure year-round comfort and energy conservation.
Shaban, N.; Maheshwari, G. P.; Suri, R. K.
Seminar 14 - Desiccant Enhanced Air Conditioning: Desiccant Enhanced Evaporative Air Conditioning (Presentation)
This presentation explains how liquid desiccant based coupled with an indirect evaporative cooler can efficiently produce cool, dry air, and how a liquid desiccant membrane air conditioner can efficiently provide cooling and dehumidification without the carryover problems of previous generations of liquid desiccant systems. It provides an overview to a liquid desiccant DX air conditioner that can efficiently provide cooling and dehumidification to high latent loads without the need for reheat, explains how liquid desiccant cooling and dehumidification systems can outperform vapor compression based air conditioning systems in hot and humid climates, explains how liquid desiccant cooling and dehumidification systems work, and describes a refrigerant free liquid desiccant based cooling system.
Kozubal, E.
Study of long term options for electric vehicle air conditioning
There are strong incentives in terms of national energy and environmental policy to encourage the commercialization of electrically powered vehicles in the U.S. Among these incentives are reduced petroleum consumption, improved electric generation capacity utilization, reduced IC engine emissions, and, depending on the primary fuel used for electric power generation, reduced emissions of carbon dioxide. A basic requirement for successfully commercializing any motor vehicle in the US is provision of adequate passenger comfort heating and air conditioning (cooling). Although air conditioning is generally sold as optional equipment, in excess of 80% of the automobiles and small trucks sold in the US have air conditioning systems. In current, pre-commercial electric vehicles, comfort heating is provided by a liquid fuel fired heater that heats water which is circulated through the standard heater core in the conventional interior air handling unit. Air conditioning is provided by electric motor driven compressors, installed in a system having, perhaps, an [open quotes]upsized[close quotes] condenser and a standard evaporator (front and rear evaporators in some instances) installed in the conventional interior air handler. Although this approach is adequate in the near term for initial commercialization efforts, a number of shortcomings of this arrangement, as well as longer range concerns need to be addressed. In this project, the long term alternatives for cooling and heating electric vehicles effectively, efficiently (with minimum range penalties), and without adverse environmental impacts have been examined. Identification of options that can provide both heating and cooling is important, in view of the disadvantages of carrying separate heating and cooling systems in the vehicle.
Dieckmann, J.; Mallory, D. (Little (Arthur D.), Inc., Cambridge, MA (United States))
There are strong incentives in terms of national energy and environmental policy to encourage the commercialization of electrically powered vehicles in the U.S. Among these incentives are reduced petroleum consumption, improved electric generation capacity utilization, reduced IC engine emissions, and, depending on the primary fuel used for electric power generation, reduced emissions of carbon dioxide. A basic requirement for successfully commercializing any motor vehicle in the US is provision of adequate passenger comfort heating and air conditioning (cooling). Although air conditioning is generally sold as optional equipment, in excess of 80% of the automobiles and small trucks sold in the US have air conditioning systems. In current, pre-commercial electric vehicles, comfort heating is provided by a liquid fuel fired heater that heats water which is circulated through the standard heater core in the conventional interior air handling unit. Air conditioning is provided by electric motor driven compressors, installed in a system having, perhaps, an {open_quotes}upsized{close_quotes} condenser and a standard evaporator (front and rear evaporators in some instances) installed in the conventional interior air handler. Although this approach is adequate in the near term for initial commercialization efforts, a number of shortcomings of this arrangement, as well as longer range concerns need to be addressed. In this project, the long term alternatives for cooling and heating electric vehicles effectively, efficiently (with minimum range penalties), and without adverse environmental impacts have been examined. Identification of options that can provide both heating and cooling is important, in view of the disadvantages of carrying separate heating and cooling systems in the vehicle.
Dieckmann, J.; Mallory, D. [Little (Arthur D.), Inc., Cambridge, MA (United States)
Thermal storage HVAC system retrofit provides economical air conditioning
This article describes an EMS-controlled HVAC system that meets the ventilation and cooling needs of an 18,000-seat indoor ice hockey arena. The Buffalo Memorial Auditorium (affectionately referred to as the Aud) was built in 1937 under the Works Project Administration of the federal government. Its original configuration included a 12,000-seat arena with an ice skating rink. By the late 1980s, the city was unsuccessfully attempting to attract events and tenants to the auditorium, which lacked air conditioning and other modern amenities. Thus, it was decided to renovate the facility to make it marketable. The first phase of the renovation included installing an air-conditioning system in the arena and repairing the existing building systems that were inoperable because of deferred maintenance. After considering the existing conditions (such as size of the space, intermittent usage, construction restrictions, operating budgets and the limited operations staff), the engineering team designed an innovative HVAC system. The system's features include: a carbon dioxide monitoring device that controls the intake of outside air; an ice storage system that provides chilled water and shifts electrical demand to off-peak hours; and a design that uses the building mass as a heat sink. A new energy management system (EMS) determines building cooling needs based on the type of event, ambient conditions and projected audience size. Then, it selects the most economical method to obtain the desired arena temperature.
Smith, S.F. (Wendel Engineers, P.C., Buffalo, NY (United States))
Alternative non-CFC mobile air conditioning
Concern about the destruction of the global environment by chlorofluorocarbon (CFC) fluids has become an impetus in the search for alternative, non-CFC refrigerants and cooling methods for mobile air conditioning (MAC). While some alternative refrigerants have been identified, they are not considered a lasting solution because of their high global warming potential, which could result in their eventual phaseout. In view of this dilemma, environmentally acceptable alternative cooling methods have become important. This report, therefore, is aimed mainly at the study of alternative automotive cooling methodologies, although it briefly discusses the current status of alternative refrigerants. The alternative MACs can be divided into work-actuated and heat-actuated systems. Work-actuated systems include conventional MAC, reversed Brayton air cycle, rotary vane compressor air cycle, Stirling cycle, thermoelectric (TE) cooling, etc. Heat-actuated MACs include metal hydride cooling, adsorption cooling, ejector cooling, absorption cycle, etc. While we are better experienced with some work-actuated cycle systems, heat-actuated cycle systems have a high potential for energy savings with possible waste heat applications. In this study, each altemative cooling method is discussed for its advantages and its limits.
Mei, V.C.; Chen, F.C.; Kyle, D.M.
Effect of Intake Air Filter Condition on Vehicle Fuel Economy
The U.S. Department of Energy (DOE) Office of Energy Efficiency and Renewable Energy and the U.S. Environmental Protection Agency (EPA) jointly maintain a fuel economy website (www.fueleconomy.gov), which helps fulfill their responsibility under the Energy Policy Act of 1992 to provide accurate fuel economy information [in miles per gallon (mpg)] to consumers. The site provides information on EPA fuel economy ratings for passenger cars and light trucks from 1985 to the present and other relevant information related to energy use such as alternative fuels and driving and vehicle maintenance tips. In recent years, fluctuations in the price of crude oil and corresponding fluctuations in the price of gasoline and diesel fuels have renewed interest in vehicle fuel economy in the United States. (User sessions on the fuel economy website exceeded 20 million in 2008 compared to less than 5 million in 2004 and less than 1 million in 2001.) As a result of this renewed interest and the age of some of the references cited in the tips section of the website, DOE authorized the Oak Ridge National Laboratory (ORNL) Fuels, Engines, and Emissions Research Center (FEERC) to initiate studies to validate and improve these tips. This report documents a study aimed specifically at the effect of engine air filter condition on fuel economy. The goal of this study was to explore the effects of a clogged air filter on the fuel economy of vehicles operating over prescribed test cycles. Three newer vehicles (a 2007 Buick Lucerne, a 2006 Dodge Charger, and a 2003 Toyota Camry) and an older carbureted vehicle were tested. Results show that clogging the air filter has no significant effect on the fuel economy of the newer vehicles (all fuel injected with closed-loop control and one equipped with MDS). The engine control systems were able to maintain the desired AFR regardless of intake restrictions, and therefore fuel consumption was not increased. The carbureted engine did show a decrease in fuel economy with increasing restriction. However, the level of restriction required to cause a substantial (10-15%) decrease in fuel economy (such as that cited in the literature) was so severe that the vehicle was almost undrivable. Acceleration performance on all vehicles was improved with a clean air filter. Once it was determined how severe the restriction had to be to affect the carbureted vehicle fuel economy, the 2007 Buick Lucerne was retested in a similar manner. We were not able to achieve the level of restriction that was achieved with the 1972 Pontiac with the Lucerne. The Lucerne's air filter box would not hold the filter in place under such severe conditions. (It is believed that this testing exceeded the design limits of the air box.) Tests were conducted at a lower restriction level (although still considerably more severe than the initial clogged filter testing), allowing the air filter to stay seated in the air box, and no significant change was observed in the Lucerne's fuel economy or the AFR over the HFET cycle. Closed-loop control in modern fuel injected vehicle applications is sophisticated enough to keep a clogged air filter from affecting the vehicle fuel economy. However for older, open-loop, carbureted vehicles, a clogged air filter can affect the fuel economy. For the vehicle tested, the fuel economy with a new air filter improved as much as 14% over that with a severely clogged filter (in which the filter was so clogged that drivability was impacted). Under a more typical state of clog, the improvement with a new filter ranged from 2 to 6%.
Norman, Kevin M [ORNL; Huff, Shean P [ORNL; West, Brian H [ORNL
Keeping Cool Without Air Conditioning | Department of Energy
Keeping Cool Without Air Conditioning Keeping Cool Without Air Conditioning August 2, 2013 - 9:50am Addthis Trees can save you energy by blocking sunlight in the summer and letting...
Feature - Air Force Fellows helping work toward smarter diesel engines
Air Force Fellows helping work toward smarter diesel engines Air Force Fellows helping work toward smarter diesel engines Air Force Fellows Clint Abell (left) and Jeff Gillen work on Smarter Diesel Engine (SDE) 21. The project involves using ion sensors to help the engine run at maximum efficiency. Air Force Fellows Clint Abell (left) and Jeff Gillen work on Smarter Diesel Engine (SDE) 21. The project involves using ion sensors to help the engine run at maximum efficiency. (Photo by Wes Agresta) One of the three core values of the Air Force is "excellence in all we do." So it should be no surprise that there are currently two Air Force officers here at Argonne studying ways to improve the efficiency of military vehicles. Lieutenant Colonel Jeff Gillen and Major Clint Abell are the fourth set of Air Force Fellows to spend time at Argonne, but the first to be stationed
Magnetic Refrigeration Technology for High Efficiency Air Conditioning
Magnetic refrigeration was investigated as an efficient, environmentally friendly, flexible alternative to conventional residential vapor compression central air conditioning systems. Finite element analysis (FEA) models of advanced geometry active magnetic regenerator (AMR) beds were developed to minimize bed size and thus magnet mass by optimizing geometry for fluid flow and heat transfer and other losses. Conventional and magnetocaloric material (MCM) regenerator fabrication and assembly techniques were developed and advanced geometry passive regenerators were built and tested. A subscale engineering prototype (SEP) magnetic air conditioner was designed, constructed and tested. A model of the AMR cycle, combined with knowledge from passive regenerator experiments and FEA results, was used to design the regenerator beds. A 1.5 Tesla permanent magnet assembly was designed using FEA and the bed structure and plenum design was extensively optimized using FEA. The SEP is a flexible magnetic refrigeration platform, with individually instrumented beds and high flow rate and high frequency capability, although the current advanced regenerator geometry beds do not meet performance expectations, probably due to manufacturing and assembly tolerances. A model of the AMR cycle was used to optimize the design of a 3 ton capacity magnetic air conditioner, and the system design was iterated to minimize external parasitic losses such as heat exchanger pressure drop and fan power. The manufacturing cost for the entire air conditioning system was estimated, and while the estimated SEER efficiency is high, the magnetic air conditioning system is not cost competitive as currently configured. The 3 ton study results indicate that there are other applications where magnetic refrigeration is anticipated to have cost advantages over conventional systems, especially applications where magnetic refrigeration, through the use of its aqueous heat transfer fluid, could eliminate intermediate heat exchangers or oil distribution issues found in traditional vapor compression systems.
Boeder, A; Zimm, C
Air-Conditioning, Heating, and Refrigeration Institute (AHRI...
Conditioning, Heating, and Refrigeration Institute (AHRI) Regulatory Burden RFI Air-Conditioning, Heating, and Refrigeration Institute (AHRI) Regulatory Burden RFI These comments...
Closed-loop air cooling system for a turbine engine
Method and apparatus are disclosed for providing a closed-loop air cooling system for a turbine engine. The method and apparatus provide for bleeding pressurized air from a gas turbine engine compressor for use in cooling the turbine components. The compressed air is cascaded through the various stages of the turbine. At each stage a portion of the compressed air is returned to the compressor where useful work is recovered.
North, William Edward (Winter Springs, FL)
Innovative Systems for Solar Air Conditioning of Buildings
Solar air conditioning is an attractive technology to achieve comfortable room conditions, especially in hot and sunny climates. In particular air conditioning systems based on sorption technologies offer several advantages as they can be designed for a high efficient utilization of solar thermal energy. To show the today's and near future potential innovative solar cooling and air conditioning systems are discussed which are well adapted to the utilization of solar energy. The system performance of each air conditioning system is evaluated under Abu Dhabi design conditions.
Kessling, W.; Peltzer, M.
Investigation of Residential Central Air Conditioning Load Shapes in
LBNL-52235 Investigation of Residential Central Air Conditioning Load Shapes in NEMS Kristina Laboratory is an equal opportunity employer. #12;#12;LBNL-52235 Investigation of Residential Central Air;#12;Investigation of Residential Central Air Conditioning Load Shapes in NEMS i Table of Contents Acronyms
Analysis of a Dedicated Outdoor Air System and Low Temperature Supply Air Conditioning System
This paper presents the principles and the characteristics of a dedicated outdoor air system (DOAS) and low temperature supply air system. DOAS is offered based on the demands of indoor air quality and the low temperature supply air system is offered based on the demands of saving energy. The two systems are very similar, which is analyzed in this paper. Using actual engineering, we compute the air flow rate, cold load and energy consumption in detail, and provide some good conclusions.
Guang, L.; Li, R.
Effects of operating conditions, compression ratio, and gasoline reformate on SI engine knock limits
A set of experiments was performed to investigate the effects of air-fuel ratio, inlet boost pressure, hydrogen rich fuel reformate, and compression ratio on engine knock behavior. For each condition the effect of spark ...
Gerty, Michael D
Alternative Air Conditioning Technologies: Underfloor Air Distribution (UFAD)
is defined as any space conditioning system that allowsor by a separate space conditioning system, but in eitherenergy use - As with any space conditioning system, a poorly
Webster, Tom
Nuclear Maintenance Applications Center: Heating, Ventilating, and Air Conditioning Specialist Guide
The people responsible for heating, ventilating, and air conditioning (HVAC) in the nuclear power industry are known by various titles--HVAC specialist, HVAC component engineer, HVAC system manager, and HVAC system engineer, to name a few. Although HVAC duties and responsibilities are often spread across several departments, such as maintenance, operations, engineering, and procurement, it is up to the HVAC specialist to ensure that HVAC system and component health and reliability are maintained. This re...
Life-cycle cost and payback period analysis for commercial unitary air conditioners
Prices Computed from Air Conditioning Load Reductions UsingRefrigerating and Air-Conditioning Engineers, Inc. (ASHRAE)/Refrigerating and Air-Conditioning Engineers, Inc. (ASHRAE),
Rosenquist, Greg; Coughlin, Katie; Dale, Larry; McMahon, James; Meyers, Steve
An Analysis of Price Determination and Markups in the Air-Conditioning and Heating Equipment Industry
of Commercial and Residential Air Conditioning and HeatingOF COMMERCIAL AND RESIDENTIAL AIR-CONDITIONING AND HEATINGand residential air-conditioning and heating equipment.
Using Modelica for Physical Modeling of Air-Conditioning Systems
Using Modelica for Physical Modeling of Air-Conditioning Systems Using Modelica for Physical Modeling of Air-Conditioning Systems Speaker(s): Jonas Eborn Date: August 23, 2007 - 12:00pm Location: 90-4133 Seminar Host/Point of Contact: Michael Wetter The Air Conditioning library is a commercial Modelica library for the steady-state and transient simulation of air conditioning systems using both compact micro-channel heat exchangers as well as fin-and-tube type heat exchangers. Currently it is mostly used by automotive OEMs and suppliers that need high-accuracy system level models to evaluate energy efficiency of systems developed under the pressure of reduced design cycle times. The library also has applications in other areas, including aircraft cooling systems and residential air-conditioning. The Air Conditioning library contains published correlations for heat and mass transfer and
Apparatus for controlling the air-fuel ratio in an internal combustion engine
Apparatus for controlling the air-fuel ratio in an internal combustion engine to substantially maintain the ratio at a predetermined value while the engine is operating under various load conditions. The engine has a carburetor with an air passageway through which air is drawn into the engine. Fuel is supplied to the carburetor through a fuel system and mixed with air passing through the carburetor. The presence of oxygen in the combustion products, which is a function of the air-fuel ratio of the mixture, is sensed and a first electrical signal representative of the oxygen content is supplied. The first electrical signal is compared with a predetermined reference level which is a function of the predetermined value to produce a second electrical signal having first and second signal elements, a first signal element being produced when the air-fuel ratio of the mixture is greater than the predetermined level and a second signal element being produced when the ratio is less than the level. A control responsive to the second electrical signal supplies to an air metering unit a control signal by which the quantity of air introduced into the fuel system is controlled. A change in the control signal is produced whenever the second electrical signal has a transition from one signal element to the other thereby for the air metering unit to change the quantity of air introduced into the fuel system conduit by an amount necessary to substantially maintain the air-fuel ratio at the predetermined value.
Gantzert, T.R.; Hicks, D.L.; Lindberg, A.W.
Weatherking Heating & Air conditioning | Open Energy Information
Open Energy Info (EERE)
Page Page Edit with form History Facebook icon Twitter icon » Weatherking Heating & Air conditioning Jump to: navigation, search Name Weatherking Heating & Air conditioning Address 51 Meadow Lane Place Northfield, Ohio Zip 44067 Sector Buildings, Efficiency, Geothermal energy, Renewable Energy, Services Product Business and legal services; Energy audits/weatherization; Energy provider: power production;Energy provider: wholesale;Engineering/architectural/design;Installation;Investment/finances;Maintenance and repair; Retail product sales and distribution Phone number 330-908-0281 Website http://www.weatherking1.com Coordinates 41.3340869°, -81.530299° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":41.3340869,"lon":-81.530299,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}
Modeling and construction of a computer controlled air conditioning system.
??As energy efficient devices become more necessary, it is desired to increase the efficiency of air conditioning systems. Current systems use on/off control, where the� (more)
Frink, Brandon S.
and ready-to-use models for all relevant components of automotive air conditioning systems like condenser, evaporator, compressor, expansion devices and accumulatorreceiver...
New and Underutilized Heating, Ventilation, and Air Conditioning...
8, 2013 - 2:56pm Addthis The following heating, ventilation, and air conditioning (HVAC) technologies are underutilized within the Federal sector. These technologies have been...
2001 Consumption and Expenditures -- Electric Air-Conditioning ...
U.S. Energy Information Administration (EIA)
CE3-1c. Electric Air-Conditioning Energy Consumption in U.S. Households by Climate Zone, 2001 : 2: CE3-2c. ...
Date | 1Refrigeration and Air Conditioning EMA Education and Training Date | 2Refrigeration and Air Conditioning EMA Education and Training
Date | 1Refrigeration and Air Conditioning EMA Education and Training #12;Date | 2Refrigeration Flow Coil Design etc. Finger Print Relationship Every evaporator is unique Unstable Region * = examples
Oak Ridge National Laboratory
Design of Air-cooled Microchannel Condensers for Mal-distributed Air Flow Conditions .
??Air-cooled condensers are routinely designed for a variety of applications, including residential air-conditioning systems. Recent attempts at improving the performance of these heat exchangers have� (more)
Subramaniam, Vishwanath
Air Conditioning Load Prediction Based on DE-SVM Algorithm
Based on SVM (Support Vector Machine) theory, and the model to predict air conditioning load was established. In order to optimize the behavior of SVM, the DE (Differential Evolution) algorithm was introduced into classic SVM. The DE-SVM model is applied ... Keywords: Air Conditioning load, DE-SVM, Prediction
Zhonghai Chen; Yong Sun; Guoli Yang; Tengfei Wu; Guizhu Li; Longbiao Xin
The Feasibility Analysis of a New Air-Conditioning System
This paper presents a new modular solar refrigeration and liquid desiccant air conditioning system composed by adsorption refrigeration system, liquid desiccant system and roof cold radiation. The feasibility and beneficial of this new system are analyzed ... Keywords: liquid desiccant, modular solar refrigeration, new air conditioning system, roof cold radiation, technical and economic feasibility analysis
Jinggang Wang; Meixia Du; Xiaoxia Gao; Jin Zhao; Zhenjiang Yin; Yi Man
Air conditioning system with supplemental ice storing and cooling capacity
The present air conditioning system with ice storing and cooling capacity can generate and store ice in its pipe assembly or in an ice storage tank particularly equipped for the system, depending on the type of the air conditioning system. The system is characterized in particular in that ice can be produced and stored in the air conditioning system whereby the time of supplying cooled air can be effectively extended with the merit that the operation cycle of the on and off of the compressor can be prolonged, extending the operation lifespan of the compressor in one aspect. In another aspect, ice production and storage in great amount can be performed in an off-peak period of the electrical power consumption and the stored ice can be utilized in the peak period of the power consumption so as to provide supplemental cooling capacity for the compressor of the air conditioning system whereby the shift of peak and off-peak power consumption can be effected with ease. The present air conditioning system can lower the installation expense for an ice-storing air conditioning system and can also be applied to an old conventional air conditioning system.
Weng, Kuo-Lianq (Taichung, TW); Weng, Kuo-Liang (Taichung, TW)
BEETIT: Building Cooling and Air Conditioning
BEETIT Project: The 14 projects that comprise ARPA-E�s BEETIT Project, short for �Building Energy Efficiency Through Innovative Thermodevices,� are developing new approaches and technologies for building cooling equipment and air conditioners. These projects aim to drastically improve building energy efficiency and reduce greenhouse gas emissions such as carbon dioxide (CO2) at a cost comparable to current technologies.
NREL: Vehicle Ancillary Loads Reduction - Air Conditioning and Emissions
Conditioning and Emissions Conditioning and Emissions Air conditioning and indirect emissions go together in the sense that when a vehicle's air conditioning system is in use, fuel economy declines. When more petroleum fuel is burned, more pollution and greenhouse gases are emitted. An additional, "direct" source of greenhouse gas emissions is the refrigerant used in air conditioning. Called HFC-134a, this pressurized gas tends to seep through tiny openings and escapes into the atmosphere. It can also escape during routine service procedures such as system recharging. NREL's Vehicle Ancillary Loads Reduction team applied its vehicle systems modeling expertise in a study to predict fuel consumption and indirect emissions resulting from the use of vehicle air conditioning. The analysis
Neural network control for an intelligent air handler in an air-conditioning system.
??Many commercial air-conditioning systems in hot and humid areas like Singapore are operated throughout the year. There are two main classifications for these systems: the� (more)
Zhang, Qi.
Direct Digital Control in Air Conditioning Systems for Energy Efficiency
With the rapid development of Intelligent Buildings (IB), the Building Automation System (BAS) has come to control and manage the equipment in the building more and more scientifically, economically and rationally, which can not only raise the function and the level of the building, but also save energy. At present, air-conditioning design in internal commercial buildings is becoming more complex and enormous. The proportion of air conditioning systems in the whole building is getting larger. In order to control and manage the air-conditioning systems effectively and take full use of energy-saving technology, we apply computer control to the system of air automation control. This paper discusses direct digital control (DDC) in the air conditioning system in buildings.
Liu, W.; Ye, A.; Li, D.
Heating, Ventilation, and Air Conditioning Renovations | Department of
Heating, Ventilation, and Air Conditioning Renovations Heating, Ventilation, and Air Conditioning Renovations Heating, Ventilation, and Air Conditioning Renovations October 16, 2013 - 4:49pm Addthis Renewable Energy Options for HVAC Renovations Geothermal Heat Pumps (GHP) Solar Water Heating (SWH) Biomass Passive Solar Heating Biomass Heating Solar Ventilation Air Preheating Federal building renovations that encompass the heating, ventilation, and air conditioning (HVAC) systems in a facility provide a range of renewable energy opportunities. The primary technology option for HVAC renovations is geothermal heat pumps (GHP). Other options include leveraging a solar water heating (SWH) system to offset heating load or using passive solar heating or a biomass-capable furnace or boiler. Some facilities may also take
Air-Conditioning Effect Estimation for Mid-Term Forecasts of Tunisian Electricity Consumption
: Engineering-industry, secondary: Econometrics. 1 Introduction The electric power mid-term loads forecasting: Estimated annual temperature sensitive electricity load components 3 Mid-term load forecasting StatisticalAir-Conditioning Effect Estimation for Mid-Term Forecasts of Tunisian Electricity Consumption
Paris-Sud XI, Université de
Developer Air Force Center for Engineering and the Environment...
en.openei.orgwikiSpecial:SearchByPropertyDeveloperAir-20Force-20Center-20for-20Engineering-20and-20the-20Environment" Special pages About us Disclaimers Energy blogs...
Hydrogen-air mixing evaluation in reciprocating engines
This report presents the results of a computational study of fuel-air mixing in a hydrogen jet using a spark-ignited, hydrogen-fueled engine. The computational results were compared with experimental measurement being conducted at the Musashi Institute of Technology in Tokyo, Japan. The hydrogen-air mixing work was directed at understanding the extreme sensitivity of ignition to spark plug location and spark timing in direct-injected, hydrogen-fueled engines.
Dodge, L; Naegeli, D [Southwest Research Inst., San Antonio, TX (United States)
Development of a Novel Air Hybrid Engine.
??An air hybrid vehicle is an alternative to the electric hybrid vehicle that stores the kinetic energy of the vehicle during braking in the form� (more)
Fazeli, Amir
Desiccant Enhanced Evaporative Air Conditioning: Parametric Analysis and Design; Preprint
This paper presents a parametric analysis using a numerical model of a new concept in desiccant and evaporative air conditioning. The concept consists of two stages: a liquid desiccant dehumidifier and a dew-point evaporative cooler. Each stage consists of stacked air channel pairs separated by a plastic sheet. In the first stage, a liquid desiccant film removes moisture from the process (supply-side) air through a membrane. An evaporatively-cooled exhaust airstream on the other side of the plastic sheet cools the desiccant. The second-stage indirect evaporative cooler sensibly cools the dried process air. We analyze the tradeoff between device size and energy efficiency. This tradeoff depends strongly on process air channel thicknesses, the ratio of first-stage to second-stage area, and the second-stage exhaust air flow rate. A sensitivity analysis reiterates the importance of the process air boundary layers and suggests a need for increasing airside heat and mass transfer enhancements.
Woods, J.; Kozubal, E.
Residential Air-Conditioning System with Smart-Grid Functionality.
??This thesis sets forth a novel intelligent residential air-conditioning (A/C) system controller that provides optimal thermal comfort and electricity cost trade-offs for a household resident� (more)
Thomas, Auswin George
Intelligent Control of Heating, Ventilating and Air Conditioning Systems
This paper proposed a simulation-optimization energy saving strategy for heating, ventilating and air conditioning (HVAC) systems' condenser water loop through intelligent control of single speed cooling towers' components. An analysis of system components ...
Patrick Low Kie; Lau Bee Theng
Approaches to Selecting Design Temperatures for Air-Conditioning
Approaches to Selecting Design Temperatures for Air-Conditioning Speaker(s): Eric Peterson Date: July 7, 2005 - 12:00pm Location: 90-3122 Seminar HostPoint of Contact: Philip...
Fuel-cell engine stream conditioning system
A stream conditioning system for a fuel cell gas management system or fuel cell engine. The stream conditioning system manages species potential in at least one fuel cell reactant stream. A species transfer device is located in the path of at least one reactant stream of a fuel cell's inlet or outlet, which transfer device conditions that stream to improve the efficiency of the fuel cell. The species transfer device incorporates an exchange media and a sorbent. The fuel cell gas management system can include a cathode loop with the stream conditioning system transferring latent and sensible heat from an exhaust stream to the cathode inlet stream of the fuel cell; an anode humidity retention system for maintaining the total enthalpy of the anode stream exiting the fuel cell related to the total enthalpy of the anode inlet stream; and a cooling water management system having segregated deionized water and cooling water loops interconnected by means of a brazed plate heat exchanger.
DuBose, Ronald Arthur (Marietta, GA)
Reducing Air-Conditioning System Energy Using a PMV Index
The control system of central air-conditioning, based on PMV, not only improves thermal comfort but also reduces system energy consumption. A new thermal comfort degree softsensor model is built via use of the CMAC neural network nonlinear calibration function. It can realize on-line detection of thermal comfort. At the same time it can also realize real-time control of central air-conditioning system based on PMV. Simulation results demonstrate the simplicity and effectiveness of the presented method.
Li, H.; Zhang, Q.
Approaches to Selecting Design Temperatures for Air-Conditioning Approaches to Selecting Design Temperatures for Air-Conditioning Speaker(s): Eric Peterson Date: July 7, 2005 - 12:00pm Location: 90-3122 Seminar Host/Point of Contact: Philip Haves Edward A. Arens The presentation will describe and compare the methods of determining cooling design conditions used by ASHRAE and the Australian Institute of Refrigeration, Air-Conditioning and Heating. A case study based on weather data for Brisbane will be used to illustrate the issues that arise. One issue is the usefulness of the 3-hourly temperature observations archived in International Weather Office records compared to the hourly observations required by the ASHRAE method. Another issue is the use of daily maxima, which have been archived for over 100 years at many Australian locations. Daily data can easily be used to find trends
Room Air Conditioning Energy Efficiency and Demand Response Potential
Room or window air conditioners are a common appliance in parts of the United States residential sector for providing summertime cooling. The technology is based on the same vapor compression cycle common in central air conditioning and refrigeration applications, but with all system components in one enclosure, which is generally small and comparatively inexpensive. The systems are simple and modular enough to be installed by the homeowner, and can be installed in windows without major modification, or ...
Commentary: Air-conditioning as a risk for increased use of health services
55476 Commentary: Air-conditioning as a risk for increased5-14-04 Commentary: Air-conditioning as a risk for increasedof office buildings with air-conditioning systems (e.g. ,
Mendell, Mark J.
Accurate Air Engineering, Inc. and Kraft Foods Teaming Profile | ENERGY
Accurate Air Engineering, Inc. and Kraft Foods Teaming Profile Accurate Air Engineering, Inc. and Kraft Foods Teaming Profile Secondary menu About us Press room Contact Us Portfolio Manager Login Facility owners and managers Existing buildings Commercial new construction Industrial energy management Small business Service providers Service and product providers Verify applications for ENERGY STAR certification Design commercial buildings Energy efficiency program administrators Commercial and industrial program sponsors Associations State and local governments Federal agencies Tools and resources Training In This Section Campaigns Commercial building design Communications resources Energy management guidance Financial resources Portfolio Manager Products and purchasing Recognition Research and reports Service and product provider (SPP) resources
Energy Conservation of Air Conditioning Systems in Large Public Buildings
Analyzing the actuality of the large-scale public buildings' energy consumption, we know that most of them run not only in low efficiency, but also in high energy consumption. According to the characteristics of the building, we should proceed with the heating characteristics of the exterior -protected construction, the set value of the temperature of the air-conditioning, the lectotype of the Central air-conditioning system, the regulation and the modification of the transmission and distribution system, the use of the new energy and the daily management or the method of adjustment and control, and so on , so we can make the air-conditioning system run efficiently. Analyzing and comparing the large-scale public buildings' energy consumption with each other, some pointed improvement measures are proposed further. According to the study and analysis, even though large-scale public buildings consume a great of energy, there exists a huge potential for energy conservation.
Liu, P.; Li, D.
Non-CFC air conditioning for transit buses
In the United Sates, more than 80% of transit city buses are air conditioned. Vapor compression refrigeration systems are standard for air conditioning buses and account for up to 25% of fuel consumption in the cooling season. Vapor compression devices use chlorofluorocarbons (CFCs), chemicals that contributes to Earths`s ozone depletion and to global warming. Currently, evaporative cooling is an economical alternative to CFC vapor compression refrigeration for air conditioning buses. It does not use CFCs but is restricted in use to arid climates. This limitation can be eliminated by dehumidifying the supply air using desiccants. We studied desiccant systems for cooling transit buses and found that the use of a desiccant-assisted evaporative cooling system is feasible and can deliver the required cooling. The weight and the size of the desiccant system though larger than vapor compression systems, can be easily accommodated within a bus. Fuel consumption for naming desiccant systems was about 70% less than CFC refrigeration system, resulting in payback periods of less than 2.5 years under most circumstances. This preliminary study indicated that desiccant systems combined with evaporative cooling is a CFC-free option to vapor compression refrigeration for air conditioning of transit buses. The concept is ready to be tested in a fun prototype scale in a commercial bus.
Pesaran, A.A.; Parent, Y.O.; Bharathan, D.
In the United Sates, more than 80% of transit city buses are air conditioned. Vapor compression refrigeration systems are standard for air conditioning buses and account for up to 25% of fuel consumption in the cooling season. Vapor compression devices use chlorofluorocarbons (CFCs), chemicals that contributes to Earths's ozone depletion and to global warming. Currently, evaporative cooling is an economical alternative to CFC vapor compression refrigeration for air conditioning buses. It does not use CFCs but is restricted in use to arid climates. This limitation can be eliminated by dehumidifying the supply air using desiccants. We studied desiccant systems for cooling transit buses and found that the use of a desiccant-assisted evaporative cooling system is feasible and can deliver the required cooling. The weight and the size of the desiccant system though larger than vapor compression systems, can be easily accommodated within a bus. Fuel consumption for naming desiccant systems was about 70% less than CFC refrigeration system, resulting in payback periods of less than 2.5 years under most circumstances. This preliminary study indicated that desiccant systems combined with evaporative cooling is a CFC-free option to vapor compression refrigeration for air conditioning of transit buses. The concept is ready to be tested in a fun prototype scale in a commercial bus.
Table HC4-12a. Air Conditioning by West Census Region, Million U.S ...
Table HC4-12a. Air Conditioning by West Census Region, Million U.S. Households, 2001 Air Conditioning Characteristics RSE Column Factor: Total U.S.
Table HC4-9a. Air Conditioning by Northeast Census Region, Million ...
Table HC4-9a. Air Conditioning by Northeast Census Region, Million U.S. Households, 2001 Air Conditioning Characteristics RSE Column Factor: Total
Table AC1. Total Households Using Air-Conditioning Equipment, 2005 ...
Table AC1. Total Households Using Air-Conditioning Equipment, 2005 Million U.S. Households Type of Air-Conditioning Equipment (millions) Central System
Table AC7. Average Expenditures for Air-Conditioning by Equipment ...
Central System 5 Table AC7. Average Expenditures for Air-Conditioning by Equipment Type, 2005 Dollars per Household Type of Air-Conditioning Equipment
Effect of Intake Air Filter Condition on Light-Duty Gasoline Vehicles
Proper maintenance can help vehicles perform as designed, positively affecting fuel economy, emissions, and the overall drivability. This effort investigates the effect of one maintenance factor, intake air filter replacement, with primary focus on vehicle fuel economy, but also examining emissions and performance. Older studies, dealing with carbureted gasoline vehicles, have indicated that replacing a clogged or dirty air filter can improve vehicle fuel economy and conversely that a dirty air filter can be significantly detrimental to fuel economy. The effect of clogged air filters on the fuel economy, acceleration and emissions of five gasoline fueled vehicles is examined. Four of these were modern vehicles, featuring closed-loop control and ranging in model year from 2003 to 2007. Three vehicles were powered by naturally aspirated, port fuel injection (PFI) engines of differing size and cylinder configuration: an inline 4, a V6 and a V8. A turbocharged inline 4-cylinder gasoline direct injection (GDI) engine powered vehicle was the fourth modern gasoline vehicle tested. A vintage 1972 vehicle equipped with a carburetor (open-loop control) was also examined. Results reveal insignificant fuel economy and emissions sensitivity of modern vehicles to air filter condition, but measureable effects on the 1972 vehicle. All vehicles experienced a measured acceleration performance penalty with clogged intake air filters.
Thomas, John F [ORNL; Huff, Shean P [ORNL; West, Brian H [ORNL; Norman, Kevin M [ORNL
Ventilation and air-conditioning concept for CNGS underground areas
The aim of the CNGS project is to prove the existence of neutrino oscillation by generating an intense neutrino beam from CERN in the direction of the Gran Sasso laboratory in Italy, where two large neutrino detectors are built to detect the neutrinos. All the components for producing the neutrino beam will be situated in the underground tunnels, service galleries and chambers. The ventilation and air-conditioning systems installed in these underground areas have multiple tasks. Depending on the operating mode and structure to be air-conditioned, the systems are required to provide fresh air, cool the machine, dehumidify areas housing sensible equipment or assure the smoke removal in a case of a fire. This paper presents the technical solutions foreseen to meet these requirements.
Lindroos, J
Solutions for Summer Electric Power Shortages: Demand Response and its Applications in Air Conditioning and Refrigerating Systems
LBNL-63806 Refrigeration, Air Conditioning, & Electric Powerand its Applications in Air Conditioning and Refrigeratingand its applications in Air Conditioning and refrigerating
Han, Junqiao; Piette, Mary Ann
Solar powered desiccant air conditioning system. Final report
A solar-powered desiccant air conditioning system using silica gel has been developed, and modifications to the existing unit and additional testing are proposed to demonstrate the feasibility of the unit. Conversion from a rotating bed to a fixed bed of silica gel is proposed. Some general plans for commercialization are briefly discussed. (LEW)
Not Available
Solar air conditioning system using desiccant wheel technology
The electrical energy consumption in Malaysia has increased sharply in the past few years. Modern energy efficient technologies are desperately needed for the national energy policy. In this paper, a new design of desiccant cooling is being developed ... Keywords: air-conditioning, desiccant cooling, solar thermal energy, solid desiccant
Arfidian Rachman; Sohif Mat; Taib Iskandar; M. Yahya; Azami Zaharim; Kamaruzzaman Sopian
Research on Fuzzy Regulation Strategies in the Constant Air Volume Air Conditioning System
The energy consumption of the constant air volume (CAV) system largely depends on the regulation strategies. Although some air conditioning systems are equipped with automatic regulation devices, others lack effective regulation strategies. To avoid wasting energy and presenting simple regulation methods, fuzzy regulation strategies for CAV systems are studied in this research. A CAV system of an office building is modeled and simulated with the Designer's Simulation Toolkit (DeST). The operating parameters are calculated based on the instantaneous load obtained from simulation. The operation of the system is divided into five stages according to different conception of �cold� or �hot� in different seasons. The relationship between the outdoor air temperature and the fresh air volume, and the supply air temperature is presented in the form of fuzzy rules. Then the building is simulated under different load conditions and the operating parameters are obtained from fuzzy reasoning. Finally, the effect of fuzzy strategies on energy consumption is analyzed and compared with the effects of the operating parameters obtained from simulation. The results show that energy consumption using a fuzzy regulation strategy is close to the energy consumption of knowing the exact load of the building, while the fuzzy regulation strategy can largely simplify the regulation of the air conditioning system.
Bai, T.; Zhang, J.; Ning, N.; Tong, K.; Wu, Y.; Wang, H.
Performance assessment on continuous air monitors under real operating conditions
In the nuclear industry, workers may be exposed to artificial radioactive aerosols. These aerosols are generally composed of particles with a diameter measuring between 0.1 {mu}m and 10 {mu}m. To protect workers in nuclear facilities, monitors that continuously measure radioactivity in the air are used. The main function of the monitor is to provide real-time measurement of activity concentration. Measurement of aerosol activity concentration can be affected by a number of factors specific to the aerosols and the instrument. The first part of the article will present the general operating principles of continuous air monitors (CAMs) and inherent measurement difficulties, as well as the main standard tests. The second section describes the experimental ICARE facility The ICARE facility generates standard artificial and natural radioactive aerosols for calibrating continuous air monitors under real operating conditions. (authors)
Monsanglant-Louvet, C.; Liatimi, N.; Gensdarmes, F. [Inst. of Radioprotection and Nuclear Safety- IRSN, Saclay (France)
Application of neural network for air-fuel ratio identification in spark ignition engine
In the present work, Recurrent Neural Network (RNN) is used for Air-Fuel Ratio (AFR) identification in Spark Ignition (SI) engine. AFR identification is difficult due to nonlinear and dynamic behaviour of SI engines. Delays present in the engine ... Keywords: AFR sensors, RNNs, air-fuel ratio control, air-fuel ratio sensors, engine modelling, recurrent neural networks, simulation, spark ignition engines, virtual sensors
Samir Saraswati; Satish Chand
Engine Air Intake Manifold Having Built In Intercooler
A turbocharged V type engine can be equipped with an exhaust gas recirculation cooler integrated into the intake manifold, so as to achieve efficiency, cost reductions and space economization improvements. The cooler can take the form of a tube-shell heat exchanger that utilizes a cylindrical chamber in the air intake manifold as the heat exchanger housing. The intake manifold depends into the central space formed by the two banks of cylinders on the V type engine, such that the central space is effectively utilized for containing the manifold and cooler.
Freese, V, Charles E. (Westland, MI)
Improving Glass Walls Thermal Resistance In Air-Conditioned Buildings
The solar radiation through an air conditioned building depends on what is called the building envelope. Building envelope consists of the surfaces that separate the inside from the building outdoors. Area, direction, and specifications of glass walls; as one of envelope surfaces; has an important impact on solar radiation. Design and construction of glass walls have significant effects on building comfort and energy consumption. This paper describes methods of improving glass walls thermal resistance in air conditioned buildings. Effect of glass wall radiation temperature on the indoor temperature distribution of building rooms is also investigated. Heat gain through various types of glass is discussed. Optimization and testing of these types are carried out theoretically and experimentally as well. A series of experiments on different types of glass with special strips is performed.
Galal, T.; Kulaib, A. M.; Alajmi, R.; Al-Ansary. A; Abuzaid, M.
ILLINOIS -RAILROAD ENGINEERING Impact of Automated Condition
oduc o Methods Mainline Efficiency U i Di t hUsing Dispatch Simulation Software Future Work #12Acoustic Bearing Detectors Wheel Impact Load Detectors Hunting Truck Detectors Truck Performance Detectors Administration (FRA) Office of Safety Analysis #12;8/27/2010 10 Slide 10 ILLINOIS - RAILROAD ENGINEERING Cost
Barkan, Christopher P.L.
Air Distribution and Microenvironment Evaluation of a Desktop Task Conditioning System
Task conditioning aims to provide each occupant with personalized clean air direct to the breathing zone. The microenvironment of a typical office workplace, consisting of two desktop task conditioning systems (a Horizontal Desk Grill (HDG) and Vertical Desk Grill (VDG)) were studied by numerical simulation. Numerical simulation by k- 3-D turbulent flow was separately conducted to study the influence of supply velocity on the microenvironment of these two desktop task conditioning systems. Three task conditioning velocities were studied. Temperature and velocity distribution, Draught Rating (DR) and Predicted Percentage of Dissatisfied (PPD) of the room and workstation were applied to study the performance of task air conditioning. Results show that the performances of HDG and VDG are almost the same. Results also show that task conditioning can provide excellent working environment when supply velocity is well designed. The supply velocity of task conditioning can be set between 0.8-1.0 m/s. However, task conditioning may cause draught, and engineers should seriously consider this problem. The results can provide important references for design and optimization of the task conditioning system.
Zheng, G.
Solar air-conditioning-active, hybrid and passive
After a discussion of summer air conditioning requirements in the United States, active, hybrid, and passive cooling systems are defined. Active processes and systems include absorption, Rankine cycle, and a small variety of miscellaneous systems. The hybrid solar cooling and dehumidification technology of desiccation is covered as well as evaporative cooling. The passive solar cooling processes covered include convective, radiative and evaporative cooling. Federal and state involvement in solar cooling is then discussed. (LEW)
Yellott, J. I.
Service center to test solar air-conditioning system
Field testing of an advanced solar-powered air-conditioning system developed under the joint Saudi Arabia-US Agreement for Cooperation in the Field of solar Energy (SOLERAS) will be conducted in Arizona over a three-phase 34-month perod. Participants in the program and their contribution are cited. The solar-Rankine alternative to conventional systems using electricity or fossil fuels. (DCK)
Fetz Plumbing, Heating & Air Conditioning | Open Energy Information
Fetz Plumbing, Heating & Air Conditioning Fetz Plumbing, Heating & Air Conditioning Jump to: navigation, search Name Fetz Plumbing, Heating & Air Conditioning Address 115 Washington Street - P.O. Box 516 Place Urbana, Ohio Zip 43078 Sector Efficiency, Geothermal energy, Services, Solar Product Installation; Maintenance and repair Phone number 937-652-1136 Website http://fetzphc.com Coordinates 40.108862°, -83.757291° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":40.108862,"lon":-83.757291,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}
High Technology Centrifugal Compressor for Commercial Air Conditioning Systems
R&D Dynamics, Bloomfield, CT in partnership with the State of Connecticut has been developing a high technology, oil-free, energy-efficient centrifugal compressor called CENVA for commercial air conditioning systems under a program funded by the US Department of Energy. The CENVA compressor applies the foil bearing technology used in all modern aircraft, civil and military, air conditioning systems. The CENVA compressor will enhance the efficiency of water and air cooled chillers, packaged roof top units, and other air conditioning systems by providing an 18% reduction in energy consumption in the unit capacity range of 25 to 350 tons of refrigeration The technical approach for CENVA involved the design and development of a high-speed, oil-free foil gas bearing-supported two-stage centrifugal compressor, CENVA encompassed the following high technologies, which are not currently utilized in commercial air conditioning systems: Foil gas bearings operating in HFC-134a; Efficient centrifugal impellers and diffusers; High speed motors and drives; and System integration of above technologies. Extensive design, development and testing efforts were carried out. Significant accomplishments achieved under this program are: (1) A total of 26 builds and over 200 tests were successfully completed with successively improved designs; (2) Use of foil gas bearings in refrigerant R134a was successfully proven; (3) A high speed, high power permanent magnet motor was developed; (4) An encoder was used for signal feedback between motor and controller. Due to temperature limitations of the encoder, the compressor could not operate at higher speed and in turn at higher pressure. In order to alleviate this problem a unique sensorless controller was developed; (5) This controller has successfully been tested as stand alone; however, it has not yet been integrated and tested as a system; (6) The compressor successfully operated at water cooled condensing temperatures Due to temperature limitations of the encoder, it could not be operated at air cooled condensing temperatures. (7) The two-stage impellers/diffusers worked well separately but combined did not match well.
Ruckes, John
Engine cooling system air venting arrangement with buoyant air purge valve
An air vent arrangement is described for the cooling system of an automotive type engine having a radiator with a coolant inlet. The engine has coolant passages communicating with the radiator through an outlet essentially horizontally disposed, tubing connecting the radiator inlet and coolant outlet, and a thermostat in the outlet horizontally movable to open and closed positions. A horizontally disposed air bleed bypass passage is located vertically above the thermostat connecting the coolant outlet to a portion of the tubing downstream of the thermostat bypassing the same when the thermostat is in a closed position for bleeding air from the cooling system. The bypass passage has a valve therein moveable between a position blocking flow of coolant through the same and a second position opening the passage permitting the bleed of air therethrough. The valve is buoyant and constructed and arranged to pivot from a non flowblocking air bleed position into a flow blocking position in response to flow of coolant into the bypass passage acting thereagainst.
Schnizlein, M.E.
Identifying Efficiency Degrading Faults in Split Air Conditioning Systems
Studies estimate that as much as 50% of packaged air conditioning systems operate in faulty conditions that degrade system efficiency. Common faults include: under- and over-charged systems (too much or too little refrigerant), faulty expansions valves (stuck valves, valve hunting, poorly tuned valve controllers), and fouled evaporators and condensers. Furthermore, air conditioning systems can often be adjusted to improve efficiency while continuing to meet cooling loads (adjusting system pressures, decreasing superheat setpoints). This study presents the design of a low cost device that can non-invasively measure system operating conditions, diagnose faults, estimate potential energy savings, and provide recommendations on how the system should be adjusted or repaired. Using eight external temperature measurements, the device potentially can detect and diagnose up to ten faults commonly found in HVAC systems. Steady state temperatures are compared to threshold values obtained from literature and HVAC manufacturers to detect and determine the severity of faults and subsequent reductions in coefficient of performance. Preliminary tests reveal the potential for the device to detect and diagnose common efficiency-degrading faults in HVAC systems.
Terrill, T. J.; Brown, M. L.; Cheyne, R. W. Jr.; Cousins, A. J.; Daniels, B. P.; Erb, K. L.; Garcia, P. A.; Leutermann, M. J.; Nel, A. J.; Robert, C. L.; Widger, S. B.; Williams, A. G.; Rasmussen, B. P.
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the top of the tower An (earlier) alternative is to use a spray pond to cool water; disadvantages. Air conditioning, cooling towers7. Air conditioning, cooling towersg, gg, g Ron Zevenhoven �?�?bo, is the hi htemperature at which condensation begins when air is cooled at constant pressurecooled
Zevenhoven, Ron
Vehicle Transient Air Conditioning Analysis: Model Development& System Optimization Investigations
The National Renewable Energy Laboratory (NREL) has developed a transient air conditioning (A/C) system model using SINDA/FLUINT analysis software. It captures all the relevant physics of transient A/C system performance, including two-phase flow effects in the evaporator and condenser, system mass effects, air side heat transfer on the condenser/evaporator, vehicle speed effects, temperature-dependent properties, and integration with a simplified cabin thermal model. It has demonstrated robust and powerful system design optimization capabilities. Single-variable and multiple variable design optimizations have been performed and are presented. Various system performance parameters can be optimized, including system COP, cabin cool-down time, and system heat load capacity. This work presents this new transient A/C system analysis and optimization tool and shows some high-level system design conclusions reached to date. The work focuses on R-134a A/C systems, but future efforts will modify the model to investigate the transient performance of alternative refrigerant systems such as carbon dioxide systems. NREL is integrating its transient air conditioning model into NRELs ADVISOR vehicle system analysis software, with the objective of simultaneously optimizing A/C system designs within the overall vehicle design optimization.
Hendricks, T. J.
Commissioning and Diagnosis of VAV Air-Conditioning Systems
This paper presents a fault detection and diagnosis (FDD) strategy based on system knowledge, qualitative states and object-oriented statistical process control (SPC) models for typical pressure-independent variable air volume (VAV) air-conditioning systems. Eight FDD schemes are built to detect the eleven pre-defined VAV faults using the qualitative and quantitative FDD approaches within the strategy at two steps. The ten hard faults, which would affect the system operation, are analyzed at Step 1. The soft fault, which would not affect the basic system operation but would impact the supervisory controls, is analyzed at Step 2. The strategy is tested and validated on typical VAV systems involving multiple faults, both in simulation and in-situ tests. A software package is developed as a BMS-assisted automatic commissioning tool based on the FDD strategy. Off-line tests were conducted in both the simulated building and the real building.
Qin, J.; Wang, S.; Chan, C.; Xiao, F.
Reducing air conditioning waste by signalling it is cool outside
This experiment looked at the effects on residential energy consumption of providing homeowners with (1) a signalling device that indicated a conservation opportunity and (2) information feedback about their rate of energy use. The signalling device operated when the outside temperature was below 68F and the air conditioner was on. Homeowners were told that the signalling device indicated when they could cool their house effectively by opening the windows and turning off their air conditioner. Forty households were randomly assigned to one of four conditions: signalling device only, feedback only, both, neither. The results showed a significant 15.7% decrease in energy use for those households with the signalling devices. Neither the feedback nor interaction effect was significant. The advantages and disadvantages of having people in the control cycle were discussed. 4 references, 1 table.
Becker, L.J.; Seligman, C.
Liquid over-feeding air conditioning system and method
A refrigeration air conditioning system utilizing a liquid over-feeding operation is described. A liquid refrigerant accumulator-heat exchanger is placed in the system to provide a heat exchange relationship between hot liquid refrigerant discharged from condenser and a relatively cool mixture of liquid and vaporous refrigerant discharged from the evaporator. This heat exchange relationship substantially sub-cools the hot liquid refrigerant which undergoes little or no evaporation across the expansion device and provides a liquid over-feeding operation through the evaporator for effectively using 100 percent of evaporator for cooling purposes and for providing the aforementioned mixture of liquid and vaporous refrigerant.
Mei, Viung C. (Oak Ridge, TN); Chen, Fang C. (Knoxville, TN)
A refrigeration air conditioning system utilizing a liquid over-feeding operation is described. A liquid refrigerant accumulator-heat exchanger is placed in the system to provide a heat exchange relationship between hot liquid refrigerant discharged from condenser and a relatively cool mixture of liquid and vaporous refrigerant discharged from the evaporator. This heat exchange relationship substantially sub-cools the hot liquid refrigerant which undergoes little or no evaporation across the expansion device and provides a liquid over-feeding operation through the evaporator for effectively using 100 percent of evaporator for cooling purposes and for providing the aforementioned mixture of liquid and vaporous refrigerant. 1 figure.
Mei, V.C.; Chen, F.C.
Evaluation of air-conditioning compressor performance for assessment of load management potential
Residential air-conditioning contributes heavily to the electrical utilities' summer peak demand. Cycling programs in which utilities turn off air-conditioning compressors a certain percentage of each hour through remotely-controlled switches can help ...
Jerry R. Harber; Aileen Henson
Regression Forecasting of the Onset of the Indian Summer Monsoon with Antecedent Upper Air Conditions
It is shown that the recorded onset dates of the summer monsoon in southwestern India can be closely related functionally to the antecedent upper air conditions. The antecedent upper air conditions are represented by April mean values of the ...
Ernest C. Kung; Taher A. Sharif
Table HC2.6 Air Conditioning Characteristics by Type of Housing ...
Table HC2.6 Air Conditioning Characteristics by Type of Housing Unit, 2005 Million U.S. Housing Units Air Conditioning Characteristics Attached 2 to 4 Units 5 or More
An overview of solar assisted air-conditioning system application in small office buildings in Malaysia
In many regions of the world especially tropical weather in Malaysia, the demand for cooling of indoor air is growing due to increasing comfort expectations and increasing cooling loads. Air-conditioning, the most common cooling mechanism for providing ... Keywords: Malaysian climatic conditions, absorption chiller, evacuated tube solar collector, high energy consumption, peak load demand, solar assisted air conditioning system, solar energy
Lim Chin Haw; Kamaruzzaman Sopian; Yusof Sulaiman
Prediction of Air Conditioning Load Response for Providing Spinning Reserve - ORNL Report
This report assesses the use of air conditioning load for providing spinning reserve and discusses the barriers and opportunities. Air conditioning load is well suited for this service because it often increases during heavy load periods and can be curtailed for short periods with little impact to the customer. The report also provides an appendix describing the ambient temperature effect on air conditioning load.
Kueck, John D [ORNL; Kirby, Brendan J [ORNL; Ally, Moonis Raza [ORNL; Rice, C Keith [ORNL
TransForum v9n2 - Air Force Fellows and Smarter Diesel Engines
Air Force Fellows Help Work Toward Smarter Diesel Engines Air force fellows Major Clint Abell (center), Steve McConnell, Lt. Col. Jeff Gillen, Thomas Wallner and Steve Ciatti (in...
Electrical applications for air conditioning and refrigeration systems
Electrical troubleshooting is possibly the most neglected area of maintaining air conditioning and refrigeration equipment. This text explains and illustrates methods for troubleshooting the full spectrum of electrical or electronic circuits of these systems. Comprehensive sections offer coverage of electrical fundamentals, single-phase electric motors, three-phase motors, control devices, electrical control circuits, use of schematic diagrams in troubleshooting, ice makers, solid state electronics, and basic electronic controls. The author`s clear, concise coverage of controls enables one to quickly understand both how a specific type of control works, and how it is used in the system. The reader will find a wealth of useful instructions for making operational checks and troubleshooting for proper operation. The book is conveniently divided into application-specific units, making it easy to quickly find information specific to a particular job at hand.
Langley, B.C.
Solar liquid-desiccant air-conditioning system. Final report
A design for a closed, diurnal, intermittent absorption chiller for passive solar air-conditioning using liquid sorbents has been constructed and tested. LiBr-H/sub 2/O will not work with this design because of its low vapor pressure at the temperature available. The approach has possibilities using the 2 LiBr-ZrBr-CH/sub 3/OH or H/sub 2/O-NH/sub 3/ sorbent refrigerant pairs. The use of H/sub 2/O-NH/sub 3/ appears to be the better candidate because of the lower solution viscosity and less cycle weight, through tank volumes and collector requirements are similar. Further study of other refrigerant pairs such as S-Thiocyanate-ammonia is indicated, however, the difficulties encountered in construction and low potential coefficient of performance, and thus large collection area needed, makes commercialization of such a system doubtful in the foreseeable future.
This memo explains what Berkeley Lab has learned about how the residential central air-conditioning (CAC) end use is represented in the National Energy Modeling System (NEMS). NEMS is an energy model maintained by the Energy Information Administration (EIA) that is routinely used in analysis of energy efficiency standards for residential appliances. As part of analyzing utility and environmental impacts related to the federal rulemaking for residential CAC, lower-than-expected peak utility results prompted Berkeley Lab to investigate the input load shapes that characterize the peaky CAC end use and the submodule that treats load demand response. Investigations enabled a through understanding of the methodology by which hourly load profiles are input to the model and how the model is structured to respond to peak demand. Notably, it was discovered that NEMS was using an October-peaking load shape to represent residential space cooling, which suppressed peak effects to levels lower than expected. An apparent scaling down of the annual load within the load-demand submodule was found, another significant suppressor of the peak impacts. EIA promptly responded to Berkeley Lab's discoveries by updating numerous load shapes for the AEO2002 version of NEMS; EIA is still studying the scaling issue. As a result of this work, it was concluded that Berkeley Lab's customary end-use decrement approach was the most defensible way for Berkeley Lab to perform the recent CAC utility impact analysis. This approach was applied in conjunction with the updated AEO2002 load shapes to perform last year's published rulemaking analysis. Berkeley Lab experimented with several alternative approaches, including modifying the CAC efficiency level, but determined that these did not sufficiently improve the robustness of the method or results to warrant their implementation. Work in this area will continue in preparation for upcoming rulemakings for the other peak coincident end uses, commercial air conditioning and distribution transformers.
Two stroke homogenous charge compression ignition engine with pulsed air supplier
A two stroke homogenous charge compression ignition engine includes a volume pulsed air supplier, such as a piston driven pump, for efficient scavenging. The usage of a homogenous charge tends to decrease emissions. The use of a volume pulsed air supplier in conjunction with conventional poppet type intake and exhaust valves results in a relatively efficient scavenging mode for the engine. The engine preferably includes features that permit valving event timing, air pulse event timing and injection event timing to be varied relative to engine crankshaft angle. The principle use of the invention lies in improving diesel engines.
Clarke, John M. (Chillicothe, IL)
Effectiveness of Shading Air-Cooled Condensers of Air-Conditioning Systems
In air-conditioning (A/C) systems with air-cooled condensers, the condensing unit has to be kept in the open for easy access to outdoor air in order to efficiently dissipate heat. During daytime, the solar radiation falling on the surfaces of the condenser and the high ambient temperatures can be detrimental for the energy performance. The effectiveness of shading the condensing unit to mitigate this adverse impact is investigated in this paper. A limiting analysis compares the performance of several A/C systems with ideal shade to those with ideal solar heat gain. The comparison is based on a theoretical model and data from equipment catalogs. The theoretical increase in the coefficient of performance (COP) due to shading is found to be within 2.5%. Furthermore, this small improvement in ideal efficiency decreases at higher ambient temperatures, when enhancements to efficiency are more needed. The actual efficiency improvement due to shading is not expected to exceed 1%, and the daily energy savings will be lower.
ElSherbini, A.; Maheshwari, G. P.
Experimental Investigation on the Operation Performance of a Liquid Desiccant Air-conditioning System
A large share of energy consumption is taken by an air-conditioning system. It worsens the electricity load of the power network. Therefore, more and more scholars are paying attention to research on new types of air-conditioning systems that are energy- saving and environment-friendly. A liquid desiccant air conditioning system is among them, as it has a tremendous ability for power storage and low requirements for heat resources. Heat with low temperatures, such as excess heat, waste heat, and solar power, is suitable for the liquid desiccant air-conditioning system. The feasibility and economical efficiency of the system are studied in this experimental research. The result shows that when the temperature of the regeneration is about 80?, the thermodynamic coefficient of the system is about 0.6, and the supply air temperature of the air-conditioning system remains stable at 21?, the air-conditioning system can meet human comfort levels.
Liu, J.; Wang, J.; Wu, Z.; Gu, W.; Zhang, G.
Experimental Study of Air-Fuel Ratio Control Strategy for a Hydrogen Internal Combustion Engine
One of the most attractive combustive features for hydrogen fuel is its wide range of flammability. The wide flammability limits allow hydrogen engine to be operated at extremely lean air�fuel ratios compared to conventional fuels. Concepts for ... Keywords: Hydrogen internal combustion engine, Air/Fuel ratio, Control strategy
Zhong-yu Zhao; Fu-shui Liu
Potential benefits of oxygen-enriched intake air in a vehicle powered by a spark-ignition engine
A production vehicle powered by a spark-ignition engine (3.1-L Chevrolet Lumina, model year 1990) was tested. The test used oxygen-enriched intake air containing 25 and 28% oxygen by volume to determine (1) if the vehicle would run without difficulties and (2) if emissions benefits would result. Standard Federal Test Procedure (FTP) emissions test cycles were run satisfactorily. Test results of catalytic converter-out emissions (emissions out of the converter) showed that both carbon monoxide and hydrocarbons were reduced significantly in all three phases of the emissions test cycle. Test results of engine-out emissions (emissions straight out of the engine, with the converter removed) showed that carbon monoxide was significantly reduced in the cold phase. All emission test results were compared with those for normal air (21% oxygen). The catalytic converter also had an improved carbon monoxide conversion efficiency under the oxygen-enriched-air conditions. Detailed results of hydrocarbon speciation indicated large reductions in 1,3-butadiene, formaldehyde, acetaldehyde, and benzene from the engine with the oxygen-enriched air. Catalytic converter-out ozone was reduced by 60% with 25%-oxygen-content air. Although NO{sub x} emissions increased significantly, both for engine-out and catalytic converter-out emissions, we anticipate that they can be ameliorated in the near future with new control technologies. The automotive industry currently is developing exhaust-gas control technologies for an oxidizing environment; these technologies should reduce NO{sub x} emissions more efficiently in vehicles that use oxygen-enriched intake air. On the basis of estimates made from current data, several production vehicles that had low NO{sub x} emissions could meet the 2004 Tier II emissions standards with 25%-oxygen-content air.
Ng, H.K.; Sekar, R.R.
??Mechanical Engineering M.S.E. Experiments were carried out to investigate the effect of ambient air temperatures on the heat pump performance using a variable speed compressor.� (more)
Zhang, Hao
Energy.gov (U.S. Department of Energy (DOE))
OE Framework Document and Stakeholder Meeting regarding the Enforcement of the updated Energy Conservation Standards for Air Conditioners, Furnaces and Heat Pumps.
Intelligent Residential Air-Conditioning System with Smart-Grid Functionality
1 Intelligent Residential Air-Conditioning System with Smart-Grid Functionality Auswin George residential air-conditioning (A/C) system controller that has smart grid functionality. The qualifier, conditional on anticipated retail energy prices. The term "smart- grid functionality" means that retail energy
Tesfatsion, Leigh
Active improvement of air-conditioning system energy consumption with adaptive thermal comfort approach.
??The MSc research project aims to suggest improvements to building air-conditioning control systems, to reduce energy consumption while maintaining the comfort level of the occupants.� (more)
Muhammad Saleh, Muhammad Fadzli
Theoretical analysis of the steam pressure exchange ejector for an automotive air conditioning application.
?? The project conducted at The George Washington University is a computer simulation and theoretical analysis of the steam pressure exchange ejector air conditioning system� (more)
Gould, David
Effects of ambient humidity on the energy use of air conditioning equipment.
??This paper addresses the real-time use of ambient wet bulb temperature measurements in the optimization of building air conditioning system control as a means to� (more)
White, Justin George
The Stakeholders Using Strategy of Diversification for Taiwan's Business Transformation: Case on Air Conditioning Industry.
??As environmental protection issue become the most hot global issues recently, Air Conditioning Industry has to face not only its own management and marketing problems,� (more)
Hung, Li-Yun
Study of a solar-assisted air conditioning system for South Africa.
??In South Africa, a significant amount of electrical energy is used for air conditioning in commercial buildings, on account of the high humidity experienced. Due� (more)
Joseph, Jerusha Sarah.
Superheat control for air conditioning and refrigeration systems: Simulation and experiments.
??Ever since the invention of air conditioning and refrigeration in the late nineteenth century, there has been tremendous interest in increasing system efficiency to reduce� (more)
Otten, Richard J.
Demonstration and Testing of ClimaStat for Improved Rooftop Air-Conditioning Efficeincy
Presentation covers the demonstration and testing of ClimaStat for improved rooftop air-conditioning efficiency at the March 15, 2012, Federal Technology Deployment Working Group meeting.
Table CE3-3e. Electric Air-Conditioning Energy Expenditures in U.S ...
Electric Air-Conditioning Energy Expenditures in U.S. Households by Household Income, 2001 RSE Column Factor: Total 2001 Household Income Below Poverty Line Eli-
Energy studies on central and variable refrigerant flow air-conditioning systems
Air-conditioning is a major contributor to energy end-use in commercial buildings. Different types of airconditioning systems are installed in commercial buildings including packaged systems
Table HC6.7 Air-Conditioning Usage Indicators by Number of Household...
Gasoline and Diesel Fuel Update (EIA)
7 Air-Conditioning Usage Indicators by Number of Household Members, 2005 Total... 111.1 30.0 34.8 18.4 15.9...
Table CE3-1e. Electric Air-Conditioning Energy Expenditures in U.S ...
Dollars per Household4,a Electric Air-Conditioning Expenditures per Household ... per Household4 2001 Cooling Degree-Days per Household Total U.S. Households ...
Table CE3-6.1u. Electric Air-Conditioning Energy Consumption and ...
Table CE3-6.1u. Electric Air-Conditioning Energy Consumption and Expenditures by Household Member and Usage Indicators, 2001 Usage Indicators RSE Column Factor:
Impact of Vehicle Air-Conditioning on Fuel Economy, Tailpipe Emissions, and Electric Vehicle Range: Preprint
Vehicle air-conditioning can significantly impact fuel economy and tailpipe emissions of conventional and hybrid electric vehicles and reduce electric vehicle range. In addition, a new US emissions procedure, called the Supplemental Federal Test Procedure, has provided the motivation for reducing the size of vehicle air-conditioning systems in the US. The SFTP will measure tailpipe emissions with the air-conditioning system operating. Current air-conditioning systems can reduce the fuel economy of high fuel-economy vehicles by about 50% and reduce the fuel economy of today's mid-sized vehicles by more than 20% while increasing NOx by nearly 80% and CO by 70%.
Farrington, R.; Rugh, J.
Table AC6. Average Consumption for Air-Conditioning by Equipment ...
Central System 5 Table AC6. Average Consumption for Air-Conditioning by Equipment Type, 2005 Million British Thermal Units (Btu) per Household
Table CE3-6.2u. Electric Air-Conditioning Energy Consumption and ...
Table CE3-6.2u. Electric Air-Conditioning Energy Consumption and Expenditures by Square Feet and Usage Indicators, 2001 Usage Indicators RSE Column Factor:
Engineered microorganisms capable of producing target compounds under anaerobic conditions
The present invention is generally provides recombinant microorganisms comprising engineered metabolic pathways capable of producing C3-C5 alcohols under aerobic and anaerobic conditions. The invention further provides ketol-acid reductoisomerase enzymes which have been mutated or modified to increase their NADH-dependent activity or to switch the cofactor preference from NADPH to NADH and are expressed in the modified microorganisms. In addition, the invention provides isobutyraldehyde dehydrogenase enzymes expressed in modified microorganisms. Also provided are methods of producing beneficial metabolites under aerobic and anaerobic conditions by contacting a suitable substrate with the modified microorganisms of the present invention.
Buelter, Thomas (Denver, CO); Meinhold, Peter (Denver, CO); Feldman, Reid M. Renny (San Francisco, CA); Hawkins, Andrew C. (Parker, CO); Urano, Jun (Irvine, CA); Bastian, Sabine (Pasadena, CA); Arnold, Frances (La Canada, CA)
New Automotive Air Conditioning System Simulation Tool Developed in MATLAB/Simulink
Further improvements in vehicle fuel efficiency require accurate evaluation of the vehicle's transient total power requirement. When operated, the air conditioning (A/C) system is the largest auxiliary load on a vehicle; therefore, accurate evaluation of the load it places on the vehicle's engine and/or energy storage system is especially important. Vehicle simulation software, such as 'Autonomie,' has been used by OEMs to evaluate vehicles' energy performance. A transient A/C simulation tool incorporated into vehicle simulation models would also provide a tool for developing more efficient A/C systems through a thorough consideration of the transient A/C system performance. The dynamic system simulation software Matlab/Simulink was used to develop new and more efficient vehicle energy system controls. The various modeling methods used for the new simulation tool are described in detail. Comparison with measured data is provided to demonstrate the validity of the model.
Kiss, T.; Chaney, L.; Meyer, J.
Analysis of Air Conditioning Effectiveness vs. Outdoor Conditions: Traditional Bins or Joint Frequency Bins?
There are a number of methods used to estimate the effectiveness of air conditioning equipment in handling loads. Full hourly computer simulations are probably the most accurate, but lack flexibility and are more cumbersome to use than more compact approaches. Alternately, some form of binned weather data has been used with load and performance estimation carried out for each of the bin weather conditions. The most common binning method puts weather into bins of dry bulb temperature with mean coincident wet bulb temperatures. Mean coincident humidity terms lose the extreme humidity levels that commonly exist. This can lead one to assume that conditions will be held at all times, while in fact the humidity loads will not be met and discomfort, among other consequences, will result. Three-dimensional plots of the joint frequency results clearly illustrate problem areas. A better procedure, it will be shown, is to use a joint frequency bin data set, which puts hours of occurrence into a matrix with dry bulb ranges on one axis and humidity ratio ranges on the second axis. This form of binning is easily accomplished if a utility like BinMaker is used to generate the binned data set.
Cohen, B. M.
Influence of air conditioning management on heat island in Paris air street temperatures
spatial cartography of air- cooled chillers and cooling towers in the city of Paris and surroundings have); secondly the actual situation including individual air dry coolers, wet cooling towers and an urban cooling the air cooling demand. Results of a meso-scale meteorological model (MESO-NH), coupled to an urban energy
Ice storage rooftop retrofit for rooftop air conditioning
A significant fraction of the floor space in commercial and federal buildings is cooled by single-package rooftop air conditioning units. These units are located on flat roofs and usually operate during the day under hot conditions. They are usually less energy efficient than a chiller system for building cooling. Several U.S. companies are developing systems that employ ice storage in conjunction with chillers to replace older, inefficient rooftop units for improved performance and minimal use of on-peak electricity. Although the low evaporator temperatures needed for ice making tend to reduce the efficiency of the chiller, the overall operating costs of the ice storage system may be lower than that of a packaged, conventional rooftop installation. One version of this concept, the Roofberg{reg_sign} System developed by the Calmac Corporation, was evaluated on a small building at Oak Ridge National Laboratory in Oak Ridge, Tennessee. The Roofberg system consists of a chiller, an ice storage tank, and one or more rooftop units whose evaporator coils have been adapted to use a glycol solution for cooling. The ice storage component decouples the cooling demand of the building from the operation of the chiller. Therefore, the chiller can operate at night (cooler, more efficient condensing temperatures) to meet a daytime cooling demand. This flexibility permits a smaller chiller to satisfy a larger peak cooling load. Further, the system can be operated to shift the cooling demand to off-peak hours when electricity from the utility is generated more efficiently and at lower cost. This Roofberg system was successfully installed last year on a small one-story office building in Oak Ridge and is currently being operated to cool the building. The building and system were sufficiently instrumented to allow a determination of the performance and efficiency of the Roofberg system. Although the energy efficiency of a simulated Roofberg storage/chiller concept operating in the full storage mode was about equal to what could be expected through a simple rooftop efficiency upgrade, the operating costs for the Roofberg system could be much more favorable depending on the utility rate structure. The ability of Roofberg to move much of the cooling load to off-peak periods enables it to take advantage of on-peak demand charges and time-of-use electricity rates. The Roofberg system, as installed, was able to reduce the on-peak energy use of the cooling system to 35% of the on-peak energy consumption of the baseline system. A comparative analysis of a rooftop replacement and Roofberg indicated that the Roofberg system on Building 2518 would be the better economic choice over a range of demand charges and on-off peak energy prices which are typical of utility rate tariffs for commercial buildings.
Tomlinson, J.J. [Oak Ridge National Lab., TN (United States); Jennings, L.W. [Univ. of Tennessee, Knoxville (United States)
Fault Diagnosis of an Air-Conditioning System Using LS-SVM
This paper describes fault diagnosis of an air-conditioning system for improving reliability and guaranteeing the thermal comfort and energy saving. To achieve this goal, we proposed a technique which is model based fault diagnosis technique. Here, a ... Keywords: Air-Conditioning System, FDD, LS-SVM, Residuals generator
Mahendra Kumar; I. N. Kar
Impact of the Variable Refrigerant Volume Air Conditioning System on Building Energy Efficiency
The application of the variable refrigerant volume multi-zone air conditioning systems has met with mixed results since the publication of the Design Standard for Energy Efficiency of Public Buildings. This paper analyzes the characteristics of the variable refrigerant volume multi-zone air conditioning system, and discusses the advantages of its application.
Zhu, H.
Performance simulation of R410A air conditioning system with variable speeds
With the implementation of "Montreal protocol on substances that deplete the ozone layer", HCFCs especially R22 will be phased out. R410A (R32/R125,50/50wt%), as one alternative of R22, is a promising refrigerant for air conditioning ... Keywords: R410A, air conditioning, electronic expansion valve, performance, refrigerants, system simulation, variable speeds
Zaoxiao Zhang; Yongzhang Yu; Leping Zhang
Opportunities to Reduce Air-Conditioning Loads Through Lower Cabin Soak Temperatures
Air-conditioning loads can significantly reduce electric vehicle (EV) range and hybrid electric vehicle (HEV) fuel economy. In addition, a new U. S. emissions procedure, called the Supplemental Federal Test Procedure (SFTP), has provided the motivation for reducing the size of vehicle air-conditioning systems in the United States. The SFTP will measure tailpipe emissions with the air-conditioning system operating. If the size of the air-conditioning system is reduced, the cabin soak temperature must also be reduced, with no penalty in terms of passenger thermal comfort. This paper presents the impact of air-conditioning on EV range and HEV fuel economy, and compares the effectiveness of advanced glazing and cabin ventilation. Experimental and modeled results are presented.
Farrington, R.; Cuddy, M.; Keyser, M.; Rugh, J.
Retrofitting Air Conditioning and Duct Systems in Hot, Dry Climates
This technical report describes CARB's work with Clark County Community Resources Division in Las Vegas, Nevada, to optimize procedures for upgrading cooling systems on existing homes in the area to implement health, safety, and energy improvements. Detailed monitoring of five AC systems showed that three of the five systems met or exceeded air flow rate goals.
Shapiro, C.; Aldrich, R.; Arena, L.
Effects of secondary air injection during cold start of SI engines
The paucity of exhaust oxygen during cold start of automobile SI engines limits the extent of exothermic chemical reactions in the exhaust port, manifold, and catalyst. The injection of air into the exhaust system therefore ...
Lee, Dongkun
Module Development and Simulation of the Variable Refrigerant Flow Air Conditioning System under Cooling Conditions in Energyplus
As a high-efficiency air conditioning scheme, the variable refrigerant flow (VRF) air-conditioning system is finding its way into medium-sized office buildings. Based on a generic dynamic building energy simulation environment, EnergyPlus, a new module is developed and the energy usage of the VRF system is investigated. This paper compares the energy consumption of the VRF system with that of two conventional air-conditioning systems, namely, the variable air volume (VAV) system and the fan-coil plus fresh air (FPFA) system. A generic office building is used to accommodate the different types of heating, ventilating, and air conditioning (HVAC) systems. Our objective is to examine the energy consumption of the VRF system applied to office buildings and make suggestions for evaluating and making decisions on HVAC systems in the early stages of building design. Simulation results show that the energy-saving potential of the VRF system is expected to achieve 22.2 percent and 11.7 percent, compared to the VAV system and the FPFA system, respectively. An energy-usage breakdown of electricity end-users in various systems is also presented.
Zhou, Y.; Wu, J.; Wang, R.; Shiochi, S.
Air entrainment by a plunging jet under intermittent vortex conditions
This fluid dynamic video entry to the 2011 APS-DFD Gallery of Fluid Motion details the transient evolution of the free surface surrounding the impact region of a low-viscosity laminar liquid jet as it enters a quiescent pool. The close-up images depict the destabilization and breakup of the annular air gap and the subsequent entrainment of bubbles into the bulk liquid.
Kim, Kevin Jin; Li, Kevin; Kiger, Ken T
Improving the Performance of Air-Conditioning Systems in an ASEAN Climate
This paper describes an analysis of air conditioning performance under hot and humid tropical climate conditions appropriate to the Association of South East Asian Nations (ASEAN) countries. This region, with over 280 million people, has one of the fastest economic and energy consumption growth rates in the world. The work reported here is aimed at estimating the conservation potential derived from good design and control of air conditioning systems in commercial buildings.
Busch, J. F.; Warren, M. L.
Method and apparatus for controlling fuel/air mixture in a lean burn engine
The system for controlling the fuel/air mixture supplied to a lean burn engine when operating on natural gas, gasoline, hydrogen, alcohol, propane, butane, diesel or any other fuel as desired. As specific humidity of air supplied to the lean burn engine increases, the oxygen concentration of exhaust gas discharged by the engine for a given equivalence ratio will decrease. Closed loop fuel control systems typically attempt to maintain a constant exhaust gas oxygen concentration. Therefore, the decrease in the exhaust gas oxygen concentration resulting from increased specific humidity will often be improperly attributed to an excessive supply of fuel and the control system will incorrectly reduce the amount of fuel supplied to the engine. Also, the minimum fuel/air equivalence ratio for a lean burn engine to avoid misfiring will increase as specific humidity increases. A relative humidity sensor to allow the control system to provide a more enriched fuel/air mixture at high specific humidity levels. The level of specific humidity may be used to compensate an output signal from a universal exhaust gas oxygen sensor for changing oxygen concentrations at a desired equivalence ratio due to variation in specific humidity specific humidity. As a result, the control system will maintain the desired efficiency, low exhaust emissions and power level for the associated lean burn engine regardless of the specific humidity level of intake air supplied to the lean burn engine.
Kubesh, John Thomas (San Antonio, TX); Dodge, Lee Gene (San Antonio, TX); Podnar, Daniel James (San Antonio, TX)
Enhanced model and fuzzy strategy of air to fuel ratio control for spark ignition engines
Various mathematical models for the air to fuel ratio and control for spark ignition (SI) engines have been proposed to satisfy technical specifications. This paper reveals an improvement of the mean value model (MVEM) and a simple yet effective nonlinear ... Keywords: Air-fuel ratio, FOPDDT, Fuzzy control, Internal combustion, Nonlinear control
Anurak Jansri; Pitikhate Sooraksa
Air Emission Inventory for the Idaho National Engineering and Environmental Laboratory - Calendar Year 1999 Emission Report
This report presents the 1999 calendar year update of the Air Emission Inventory for the Idaho National Engineering and Environmental Laboratory (INEEL). The INEEL Air Emission Inventory documents sources and emissions of nonradionuclide pollutants from operations at the INEEL. The report describes the emission inventory process and all of the sources at the INEEL, and provides nonradionuclide emissions estimates for stationary sources.
Zohner, S.K.
Air Emission Inventory for the Idaho National Engineering and Environmental Laboratory - Calendar Year 1998 Emissions Report
This report presents the 1998 calendar year update of the Air Emission Inventory for the Idaho National Engineering and Environmental Laboratory (INEEL). The INEEL Air Emission Inventory documents sources and emissions of nonradionuclide pollutants from operations at the INEEL. The report describes the emission inventory process and all of the sources at the INEEL, and provides nonradiological emissions estimates for stationary sources.
S. K. Zohner
Computational fluid dynamics simulation of the air/suppressant flow in an uncluttered F18 engine nacelle
For the purposes of designing improved Halon-alternative fire suppression strategies for aircraft applications, Computational Fluid Dynamics (CFD) simulations of the air flow, suppressant transport, and air-suppressant mixing within an uncluttered F18 engine nacelle were performed. The release of inert gases from a Solid Propellant Gas Generator (SPGG) was analyzed at two different injection locations in order to understand the effect of injection position on the flow patterns and the mixing of air and suppression agent. An uncluttered engine nacelle was simulated to provide insight into the global flow features as well as to promote comparisons with previous nacelle fire tests and recent water tunnel tests which included little or no clutter. Oxygen concentration levels, fuel/air residence times that would exist if a small fuel leak were present, velocity contours, and streamline patterns are presented inside the engine nacelle. The numerical results show the influence of the gent release location on regions of potential flame extinction due to oxygen inerting and high flame strain. The occurrence of inflow through the exhaust ducts on the aft end of the nacelle is also predicted. As expected, the predicted oxygen concentration levels were consistently higher than the measured levels since a fire was not modeled in this analysis. Despite differences in the conditions of these simulations and the experiments, good agreement was obtained between the CFD predictions and the experimental measurements.
Lopez, A.R.; Gritzo, L.A.; Hassan, B.
Air Emission Inventory for the Idaho National Engineering Laboratory, 1993 emissions report
This report presents the 1993 update of the Air Emission Inventory for the Idaho National Engineering Laboratory (INEL). The purpose of the Air Emission Inventory is to commence the preparation of the permit to operate application for the INEL, as required by the recently promulgated Title V regulations of the Clean Air Act. The report describes the emission inventory process and all of the sources at the INEL and provides emissions estimates for both mobile and stationary sources.
A cost-effective and fuel-conserving nonelectric air conditioner that combines engine-driven compression and absorption cycles
A natural-gas-fueled electricity-producing condensing furnace with the potential of being mass produced at a cost of less than $1000 and providing a cost-effective and highly fuel-conserving alternative to virtually every residential gas furnace in the world has been developed. While this is a new system, it completely consists of existing mass-produced components including single-cylinder air-cooled engines, induction motors/generators, and control devices. Thus, timely commercialization can be expected and an important new energy technology and industry can result. However, all the benefits of this electricity-producing furnace occur during the winter. This has stimulated the search for a new system that can provide comparable benefits in terms of fuel conservation, the environment, and electric utility peak reduction during the summer, along with the prospects of a new and efficient new use for the natural gas surpluses that occur during the summer. The resulting system, which can use existing component equipment, is a commercial-size nonelectric air conditioner that consists of an automobile-type engine converted to natural gas, or possibly a diesel or combustion turbine, driving a Freon compression cycle, with virtually all of the engine reject heat from the exhaust and from the engine cooling system driving a conventional absorption air conditioning cycle.
Wicks, F.
Neural network control of air-to-fuel ratio in a bi-fuel engine
In this paper, a neural network-based control system is proposed for fine control of the intake air/fuel ratio in a bi-fuel engine. This control system is an add-on module for an existing vehicle manufacturer's electronic control units (ECUs). Typically ... Keywords: Artificial neural networks, bi-fuel engines, compressed natural gas (CNG), fuel injection control
G. Gnanam; S. R. Habibi; R. T. Burton; M. T. Sulatisky
Effect of a Radiant Panel Cooling System on Indoor Air Quality of a Conditioned Space
This paper discusses the effect of a radiant cooling panel system on an indoor air quality (IAQ) of a conditioned space. In this study, ceiling radiant cooling panel, mechanical ventilation with fan coil unit (FCU) and 100% fresh air are used. Temperature sensors are located at different locations inside the conditioned space in order to sense dry bulb temperatures, relative humidity to compare it with standard ASHRAE comfort values. The present investigation indicates that the radiant cooling system not only improves the indoor air quality but also reduces the building energy consumption in the conditioned space.
Mohamed, E.; Abdalla, K. N.
September 10, 2013 What is Seawater Air Conditioning (SWAC)?
and sewage savings through the elimination of cooling towers SWAC Solutions Waikiki SWAC (25,000 tons) Fossil conditioning systems · Cold seawater is pumped to cooling plant · The cold temperature of the seawater
Study of using oxygen-enriched combustion air for locomotive diesel engines
A thermodynamic simulation is used to study effects of O2-enriched intake air on performance and NO emissions of a locomotive diesel engine. Parasitic power of the air separation membrane required to supply the O2-enriched air is also estimated. For a given constraint on peak cylinder pressure, gross and net power output of an engine operating under different levels of O2 enrichment are compared with those obtained when a high-boost turbocharged engine is used. A 4% increase in peak cylinder pressure can result in 13% increase in net engine power when intake air with 28 vol% O2 is used and fuel injection timing retarded by 4 degrees. When the engine is turbocharged to a higher inlet boost, the same increase in peak cylinder pressure can result in only 4% improvement in power. If part of the higher exhaust enthalpies from the O2 enrichment is recovered, the power requirements of the air separator membrane can be met. O2 enrichment with its higher combustion temperatures reduces emissions of particulates and visible smoke but increases NO emissions (by up to 3 times at 26% O2 content). Therefore, exhaust gas after-treatment and heat recovery would be required if the full potential of O2 enrichment for improving the performance of locomotive diesel engines is to be realized.
Poola, R.B.; Sekar, R. [Argonne National Lab., IL (United States); Assanis, D.N. [Michigan Univ., Ann Arbor, MI (United States); Cataldi, G.R. [Association of American Railroads, Washington, DC (United States)
Laboratory Testing of the Heating Capacity of Air-Source Heat Pumps at Low Outdoor Temperature Conditions
Air-source heat pump systems offer an alternative to the common heating, ventilating, and air conditioning (HVAC) configuration of single split unitary air conditioners with gas heating. In simple terms, heat pumps are traditional air conditioning units with the added capability of running in reverse as required by the building load. Thus, where the traditional air conditioning unit has an indoor evaporator to remove heat from the space and an outdoor condenser to reject heat to the ambient environment, ...
Air Conditioning Stall Phenomenon Testing, Model Development, and Simulation
Electric distribution systems are experiencing power quality issues of extended reduced voltage due to fault-induced delayed voltage recovery (FIDVR). FIDVR occurs in part because modern air conditioner (A/C) and heat pump compressor motors are much more susceptible to stalling during a voltage sag or dip such as a sub-transmission fault. They are more susceptible than older A/C compressor motors due to the low inertia of these newer and more energy efficient motors. There is a concern that these local reduced voltage events on the distribution system will become more frequent and prevalent and will combine over larger areas and challenge transmission system voltage and ultimately power grid reliability. The Distributed Energy Communications and Controls (DECC) Laboratory at Oak Ridge National Laboratory (ORNL) has been employed to (1) test, (2) characterize and (3) model the A/C stall phenomenon.
Irminger, Philip [ORNL; Rizy, D Tom [ORNL; Li, Huijuan [ORNL; Smith, Travis [ORNL; Rice, C Keith [ORNL; Li, Fangxing [ORNL; Adhikari, Sarina [ORNL
"Table HC13.6 Air Conditioning Characteristics by South Census Region, 2005"
U.S. Energy Information Administration (EIA) Indexed Site
6 Air Conditioning Characteristics by South Census Region, 2005" 6 Air Conditioning Characteristics by South Census Region, 2005" " Million U.S. Housing Units" ,,"South Census Region" ,"U.S. Housing Units (millions)" ,,,"Census Division" ,,"Total South" "Air Conditioning Characteristics",,,"South Atlantic","East South Central","West South Central" "Total",111.1,40.7,21.7,6.9,12.1 "Do Not Have Cooling Equipment",17.8,1.4,0.8,0.2,0.3 "Have Cooling Equipment",93.3,39.3,20.9,6.7,11.8 "Use Cooling Equipment",91.4,38.9,20.7,6.6,11.7 "Have Equipment But Do Not Use it",1.9,0.5,"Q","Q","Q" "Air-Conditioning Equipment1, 2 "
Air-Conditioning, Heating, and Refrigeration Institute (AHRI) Regulatory Burden RFI
These comments are submitted by the Air-Conditioning, Heating, and Refrigeration Institute (AHRI) in response to the U.S. Department of Energy�s (DOE) notice in the August 8, 2012 Federal Register...
Proposal for a Vehicle Level Test Procedure to Measure Air Conditioning Fuel Use: Preprint
A procedure is described to measure approximate real-world air conditioning fuel use and assess the impact of thermal load reduction strategies in plug-in hybrid electric vehicles.
Rugh, J.
Table CE3-10e. Electric Air-Conditioning Energy Expenditures in U ...
Table CE3-10e. Electric Air-Conditioning Energy Expenditures in U.S. Households by Midwest Census Region, 2001 RSE Column Factor: Total U.S. Midwest Census Region
Analysis of a Retrofitted Thermal Energy Storage Air-conditioning System of a Marine Museum.
??Thermal energy storage(TES) air-conditioning system is a electrical load management technology with great potential to shift load from peak to off-peak utility periods. TES is� (more)
Yu, Po-wen
An Analysis of Price Determination and Markups in the Air-Conditioning...
An Analysis of Price Determination and Markups in the Air-Conditioning and Heating Equipment Industry NOTICE Due to the current lapse of federal funding, Berkeley Lab websites are...
Table CE3-4c. Electric Air-Conditioning Energy Consumption in U.S ...
Table CE3-4c. Electric Air-Conditioning Energy Consumption in U.S. Households by Type of Housing Unit, 2001 RSE Column Factor: Total Type of Housing Unit
A Historical Look at the Invention of Air-conditioned Comfort...
- 12:00pm Location: Bldg. 90 Seminar HostPoint of Contact: Satkartar K. Kinney Comfort air conditioning is largely an American development which grew out of the need for the...
Heavy Precipitation Events in New Jersey: Attendant Upper-Air Conditions
The first of an anticipated multipart study of atmospheric conditions occurring before and during heavy precipitation events in New Jersey, representative of the mid-Atlantic region, is presented. Upper-air data parameters were analyzed for 81 ...
Robert P. Harnack; Kirk Apffel; Joseph R. Cermak III
Table CE3-1c. Electric Air-Conditioning Energy Consumption in U.S ...
Table CE3-1c. Electric Air-Conditioning Energy Consumption in U.S. Households by Climate Zone, 2001 RSE Column Factor: Total Climate Zone1 RSE Row
"Table HC11.6 Air Conditioning Characteristics by Northeast Census Region, 2005"
6 Air Conditioning Characteristics by Northeast Census Region, 2005" 6 Air Conditioning Characteristics by Northeast Census Region, 2005" " Million U.S. Housing Units" ,,"Northeast Census Region" ,"U.S. Housing Units (millions)" ,,,"Census Division" ,,"Total Northeast" "Air Conditioning Characteristics",,,"Middle Atlantic","New England" "Total",111.1,20.6,15.1,5.5 "Do Not Have Cooling Equipment",17.8,4,2.4,1.7 "Have Coolling Equipment",93.3,16.5,12.8,3.8 "Use Cooling Equipment",91.4,16.3,12.6,3.7 "Have Equipment But Do Not Use it",1.9,0.3,"Q","Q" "Air-Conditioning Equipment1, 2 " "Central System",65.9,6,5.2,0.8 "Without a Heat Pump",53.5,5.5,4.8,0.7
Desiccant Enhanced Evaporative Air-Conditioning (DEVap): Evaluation of a New Concept in Ultra Efficient Air Conditioning
NREL has developed the novel concept of a desiccant enhanced evaporative air conditioner (DEVap) with the objective of combining the benefits of liquid desiccant and evaporative cooling technologies into an innovative 'cooling core.' Liquid desiccant technologies have extraordinary dehumidification potential, but require an efficient cooling sink. DEVap's thermodynamic potential overcomes many shortcomings of standard refrigeration-based direct expansion cooling. DEVap decouples cooling and dehumidification performance, which results in independent temperature and humidity control. The energy input is largely switched away from electricity to low-grade thermal energy that can be sourced from fuels such as natural gas, waste heat, solar, or biofuels.
Kozubal, E.; Woods, J.; Burch, J.; Boranian, A.; Merrigan, T.
Economic Analysis of a Waste Water Resource Heat Pump Air-Conditioning System in North China
This paper describes the situation of waste water resource in north China and the characteristics and styles of a waste water resource heat pump system, and analyzes the economic feasibility of a waste water resource heat pump air-conditioning system including investment, operating fee and pay-back time. The results show that waste water resource heat pump air-conditioning system has a low investment, low operating fee and short payback time.
Chen, H.; Li, D.; Dai, X.
The Effect of Pressure Difference Control on Hydraulic Stability in a Variable Flow Air Conditioning System
This paper analyzes the effects of different pressure difference control methods on hydraulic stability in a variable flow air conditioning system when it is applied to different air conditioning water systems. According to control method and water system, it can be divided into direct return system pass-by control, direct return system terminal control, reversed return system pass-by control and reversed return system terminal control. The results indicate that reversed return system terminal control has the best hydraulic stability.
Zhang, Z.; Fu, Y.; Chen, Y.
HVAC Technology Report: A Review of Heating, Ventilation and Air Conditioning Technology and Markets
For many of us, roughly 95 percent of our time is spent indoors. To enable humans to spend this much time inside, mechanical equipment is necessary to provide space conditioning to control the temperature (heating and cooling), ventilation, humidity, and indoor air quality. This report introduces the heating, ventilation, and air-conditioning (HVAC) industry to EPRI member utility employees. The document describes the most common technologies and applications and provides an overview of industry statisti...
Analysis of Energy Saving in a Clean Room Air-conditioning System
To address the issue of the substantial energy cost and operating cost of an all-return air system for a clean room, we changed the former system to a 2nd return air system. With the newest building energy simulation program, Energy Plus, we simulated and compared the summer energy consuming conditions of the two systems. Results prove the superiority of the 2nd return air system, and the validity of the simulation. Also, the air system energy performance in summer was illustrated with typical meteorological hour-to-hour data.
Liu, S.; Liu, J.; Pei, J.; Wang, M.
Test and Reconstruction of Air Conditioning System in a Hotel Lobby
Two air conditioning systems are equipped in a hotel lobby. It is found from the field test that the actual air rate is 40% and 16% of the nominal value, respectively, of the two systems, which is far lower than the design requirement. The air rate of the outlets varies greatly, and the coefficient of uniformity is 129.1% and 111.6% respectively of the two systems. Air distribution in the lobby is bad and thermal comfort is poor. Moreover, sharp reduction of return air makes portions of fresh air increase, which will lead to high energy consumption. Reconstruction is carried out to improve the thermal environment with the assistance of the CFD method. First, the original system is simulated by CFD method to verify the CFD method and propose modification suggestions. Then air conditioning load and air rate of the lobby is recalculated and duct redesigned. Simulation results show that the air distribution and thermal comfort of the improved scheme can meet the design requirement. The reconstructed system has been running for about two years and has shown good performance.
Wang, G.; Hu, Y.; Hu, S.; Chen, Q.
Under Review for Publication in ASME J. Solar Energy Engineering SOL-12-1058 Life Estimation of Pressurized-Air Solar-Thermal Receiver Tubes
Under Review for Publication in ASME J. Solar Energy Engineering SOL-12-1058 Life Estimation of Pressurized-Air Solar-Thermal Receiver Tubes David K. Fork 1 e-mail: email@example.com John Fitch e-mail: firstname.lastname@example.com Robert I. Jetter e-mail: email@example.com The operational conditions of the solar thermal receiver
Cortes, Corinna
Fluorescence emission induced by extensive air showers in dependence on atmospheric conditions
Charged particles of extensive air showers (EAS), mainly electrons and positrons, initiate the emission of fluorescence light in the Earth's atmosphere. This light provides a calorimetric measurement of the energy of cosmic rays. For reconstructing the primary energy from an observed light track of an EAS, the fluorescence yield in air has to be known in dependence on atmospheric conditions, like air temperature, pressure, and humidity. Several experiments on fluorescence emission have published various sets of data covering different parts of the dependence of the fluorescence yield on atmospheric conditions. Using a compilation of published measurements, a calculation of the fluorescence yield in dependence on altitude is presented. The fluorescence calculation is applied to simulated air showers and different atmospheric profiles to estimate the influence of the atmospheric conditions on the reconstructed shower parameters.
Keilhauer, Bianca
Operation of Energy-Efficient Air-Conditioned Buildings: An Overview
To design an optimum HVAC airside system that provides comfort and air quality in the air-conditioned spaces with efficient energy consumption is a great challenge. This paper evaluates recent progresses of HVAC airside design for the air-conditioned spaces. The present evaluation study defines the current status, future requirements, and expectations. It has been found that, the experimental investigations should be considered in the new trend of studies, not to validate the numerical tools only, but also to provide a complete database of the airflow characteristics in the air-conditioned spaces. Based on this analysis and the vast progress of computers and associated software, the artificial intelligent technique will be a competitor candidate to the experimental and numerical techniques. Finally, the researches that relate between the different designs of the HVAC systems and energy consumption should concern with the optimization of airside design as the expected target to enhance the indoor environment.
Khalil, E. E.
Air Emission Inventory for the Idaho National Engineering Laboratory: 1992 emissions report
This report presents the 1992 Air Emission Inventory for the Idaho National Engineering Laboratory. Originally, this report was in response to the Environmental Oversight and Monitoring Agreement in 1989 between the State of Idaho and the Department of Energy Idaho Field Office, and a request from the Idaho Air Quality Bureau. The current purpose of the Air Emission Inventory is to provide the basis for the preparation of the INEL Permit-to-Operate (PTO) an Air Emission Source Application, as required by the recently promulgated Title V regulations of the Clean Air Act. This report includes emissions calculations from 1989 to 1992. The Air Emission Inventory System, an ORACLE-based database system, maintains the emissions inventory.
Stirrup, T.S.
Novel Application of Air Separation Membranes Reduces Engine NOx Emissions
Nitrogen oxide (NOx) emissions pose risks to human health, and so they need to be reduced. One very effective tool for reducing engine in-cylinder temperature and, hence NOx emissions (NOx is a strong function of temperature), is Exhaust Gas ...
Model Based Sensor System for Temperature Measurement in R744 Air Conditioning Systems
The goal is the development of a novel principle for the temperature acquisition of refrigerants in CO2 air conditioning systems. The new approach is based on measuring the temperature inside a pressure sensor, which is also needed in the system. On the basis of simulative investigations of different mounting conditions functional relations between measured and medium temperature will be derived.
Reitz, Sven; Schneider, Peter
Optimization of the Fin Heat Pipe for Ventilating and Air Conditioning with a Genetic Algorithm
This paper illustrates that use of a heat pipe as a heat-reclaiming device can significantly influence the air-conditioning system. It analyzes the heat transfer model of the uniform annular fin heat pipe under the condition of air conditioning. It establishes functions of the fin structure parameters such as height,spacing and thickness of the fin when the volume of fin is the smallest under unit temperature difference and unit quantity of heat. It uses a genetic algorithm to optimize the model of the uniform annular fin heat pipe. The calculation result shows that the method of genetic algorithm is effective.
Qian, J.; Sun, D.; Li, G.
Proposal for an Adsorption Solar-Driven Air-Conditioning Unit for Public Offices
A simple prototype air conditioning unit driven entirely by solar energy is proposed aiming at replacing the conventional vapor compression air conditioning systems which are reasonable for the global warming. The proposed model is supposed to be used in conditioning the governmental offices during the working hours in the weekdays when both the sunshine and the need for air-conditioning reach their maximum levels at the same instance. Solar adsorption refrigeration devices have no moving parts consequently they are noiseless, non-corrosive, cheap to maintain, long lasting in addition to being environmentally friendly with zero ozone depletion as well as zero global warming potentials. For these reasons, the research activities are of increasing interest in this aspect in order to provide optimum solutions for the crucial points that impede making these systems capable to meet the criteria for commercialization.
Elsamni, O. A.; Sahmarani, K.J.; Obied, F. K.
International Symposium on Air Breathing Engines, 8th, Cincinnati, OH, June 14-19, 1987, Proceedings
The present conference on air-breathing aircraft engine technology considers topics in inlet design, radial-flow turbomachinery, fuel injection and combustion systems, axial flow compressor design and performance, ramjet configurations, turbine flow phenomena, engine control and service life, fluid flow-related problems, engine diagnostic methods, propfan design, combustor performance and pollutant chemistry, combustion dynamics, and engine system analysis. Attention is given to thrust-vectoring systems, supersonic missile air intakes, three-dimensional centrifugal compressors, airblast atomizers, secondary flows in axial flow compressors, axial compressor blade tip clearance flows, hydrogen scramjets with sidewall injection, the performance of a variable-geometry turbine, advanced tip clearance control systems, rotary jet mixing, fan blade aeroelastic behavior, flow dynamics in combustion processes, and the technology of low cost turbomachinery.
Billig, F.S.
The Technical and Economical Analysis of the Air-conditioning System Usage in Residential Buildings in Beijing
In this paper, we show that the air-conditioning usage in residential buildings in Beijing grows rapidly in relation to the development of civil construction. More and more people are not satisfied with the current style of only using split air-conditioning units in residential buildings, and are using the central air-conditioning system in residential buildings. To determine the best air conditioning mode, a residential tower building with 22 layers was chosen for analysis. The advantages and disadvantages of the central air-conditioning system and the residential multi-unit air-conditioning equipment system and the LiBr absorption chiller were compared based on calculating the first-cost and the annual cost (according to providing cooling 90 days annually). The predicted results show the economical feasibility of using the refrigerating units in air-conditioning systems in Beijing region, and point out the developing directions for the future.
Sheng, G.; Xie, G.
Issues and Factors of Train Air-conditioning System Design and Operation
Like a moving building, a train's outer meteorologic parameter will change a lot with the local meteorologic parameter on the way. In this paper, we put forward the design method of the typical design period and some dynamic energy-saving ways to solve the problem. These methods consider the dynamic changes of the outer environment when the train is moving, which will supply the theoretical basis for the calculation of the dynamic load and real-time running and regulation of the train's air-conditioning. Modifications to the air-conditioning system and some advanced air conditioning systems are introduced, which are helpful for system optimization. In this paper, based on analysis of the characteristics of the air - conditioning system in foreign high speed passenger cars and demands for its acceleration, developing trends for air - conditioning systems for high speed passenger cars are pointed out and some advice is put forward. Above all, we should not only satisfy the comfort need of the passengers, but also succeed in saving energy.
Air Conditioning with Magnetic Refrigeration : An Efficient, Green Compact Cooling System Using Magnetic Refrigeration
BEETIT Project: Astronautics is developing an air conditioning system that relies on magnetic fields. Typical air conditioners use vapor compression to cool air. Vapor compression uses a liquid refrigerant to circulate within the air conditioner, absorb the heat, and pump the heat out into the external environment. Astronautics� design uses a novel property of certain materials, called �magnetocaloric materials�, to achieve the same result as liquid refrigerants. These magnetocaloric materials essentially heat up when placed within a magnetic field and cool down when removed, effectively pumping heat out from a cooler to warmer environment. In addition, magnetic refrigeration uses no ozone-depleting gases and is safer to use than conventional air conditioners which are prone to leaks.
Analysis of historical residential air-conditioning equipment sizing using monitored data
Monitored data were analyzed to determine whether residential air conditioners in the Pacific Northwest historically have been sized properly to meet or slightly exceed actual cooling requirements. Oversizing air-conditioning equipment results in a loss of efficiency because of increased cycling and also lowers humidity control. On the other hand, the penalty of undersizing air-conditioning equipment may be some loss of comfort during extremely hot weather. The monitored data consist of hourly space-conditioning electrical energy use and internal air temperature data collected during the past 7 years from 75 residences in the Pacific Northwest. These residences are equipped with central air conditioners or heat pumps. The periods with the highest cooling energy use were analyzed for each site. A standard industry sizing methodology was used for each site to determine a sizing estimate. Both the sizing recommendation based on Manual J and peak monitored loads are compared to the capacity of the installed equipment for each site to study how the actual capacity differed from both the estimate of proper sizing and from actual demands. Characteristics of the maximum cooling loads are analyzed here to determine which conditions put the highest demand on the air conditioner. Specifically, internal air temperature data are used to determine when the highest cooling loads occur, at constant thermostat settings or when the thermostat was set down. This analysis of monitored data also provides insight into the extent that occupant comfort may be affected by undersizing air conditioners. The findings of this research indicate that cooling equipment historically has often but not always been oversized beyond industry-recommended levels. However, some occupants in homes with undersized, properly sized, and, in rare occasions, even oversized cooling equipment appear to suffer because the cooling equipment cannot always provide adequate cooling. Key findings are summarized.
Lucas, R.G.
Future Air Conditioning Energy Consumption in Developing Countries and what can be done about it: The Potential of Efficiency in the Residential Sector
Henderson (2005) Home air conditioning in Europe � how muchA.A. Pavlova ( 2003). Air conditioning market saturation and+ paper 6,306 Future Air Conditioning Energy Consumption in
McNeil, Michael A.; Letschert, Virginie E.
Demonstration and Testing of ClimaStat® for Improved Rooftop Air-Conditioning Efficiency Presented at IA Technology Deployment Working Group Meeting March 15, 2012 By Dan Howett, PE Oak Ridge National Laboratory Demonstration/Testing of ClimaStat ® for Improved Efficiency of RTU Air Conditioners * Technology from Advantek Consulting - Patented by Dr. Michael West in 2003. (US Patent #6427454) - Originally demonstrated under DOE's Inventions & Innovations program. * Current demonstration sponsored by DOD's ESTCP program * Uses off-the-shelf components to either... - Modify existing packaged air conditioners, or - Incorporate changes into new RTU equipment before installation * Initial tests show 15% improvement in HVAC efficiency.
Flywheel Cooling: A Cooling Solution for Non Air-Conditioned Buildings
"Flywheel Cooling" utillzes the natural cooling processes of evaporation, ventilation and air circulation. These systems are providing low-cost cooling for distribution centers, warehouses, and other non air-conditioned industrial assembly plants with little or no internal loads. The evaporative roof cooling system keeps the building from heating up during the day by misting the roof surface with a fine spray of water -just enough to evaporate. This process keeps the roof surface at 90� levels instead of 150� and knocks out the radiant heat transfer from the roof into the building. The system is controlled by a thermostat and automatically shuts off at night or when the roof surface cools below the set point. The same control system turns on exhaust fans to load the building with cool night air. Air circulators are installed to provide air movement on workers during the day. Best results are achieved by closing dock doors and minimizing hot air infiltration during the day. The typical application will maintain inside temperatures that will average 84� -86� when outside ambient temperatures range from 98 �-100�. Many satisfied users will attest to marked improvements in employee moral and productivity, along with providing safe storage temperatures for many products. Installed "Flywheel" systems' costs are usually less than 20% of comparable air-conditioning equipment. By keeping a built up roof cooler, the system will eliminate thermal shock and extend roof life while reducing maintenance.
Abernethy, D.
Numerical Analysis of the Channel Wheel Fresh Air Ventilator Under Frosting Conditions
As new equipment, the channel wheel fresh air ventilator has become increasingly popular in recent years. However, when such equipment is operated under low ambient temperature in the freezing area in winter, the formation of frost on the outdoor waste air surface becomes problematic, leading to the degradation of the channel wheel fresh air ventilator's performance or even the shutdown of equipment. Therefore, it is necessary to have a detailed investigation on the operational characteristics of the channel wheel fresh air ventilator under frosting in order to guide its application. This paper first reports on the development of a detailed model for the channel wheel heat exchanger, which is the core part of the channel wheel fresh air ventilator under frosting conditions. The model developed, first seen in open literature, consists of a frosting sub-model and a channel wheel heat exchanger sub-model. This is followed by reporting an evaluation of the operational characteristics of a frosted channel wheel heat exchanger under different ambient conditions using the model developed. These include frost formation on the surface of the channel wheel heat exchanger, and impacts on the operational performance of the channel wheel fresh air ventilator. Furthermore, the interval of defrosting is obtained, which provides the basis for the adoption of effective defrosting measures, and thus increasing the channel wheel fresh air ventilator's energy efficiency and operating reliability.
Gao, B.; Dong, Z.; Cheng, Z.; Luo, E.
Demonstration of Natural Gas Engine Driven Air Compressor Technology at Department of Defense Industrial Facilities
Recent downsizing and consolidation of Department of Defense (DOD) facilities provides an opportunity to upgrade remaining facilities with more efficient and less polluting equipment. Use of air compressors by the DOD is widespread and the variety of tools and machinery that operate on compressed air is increasing. The energy cost of operating a natural gas engine-driven air compressor (NGEDAC) is usually lower than the cost of operating an electric-driven air compressor. Initial capital costs are offset by differences in prevailing utility rates, efficiencies of partial load operation, reductions in peak demand, heat recovery, and avoiding the cost of back-up generators. Natural gas, a clean-burning fuel, is abundant and readily available. In an effort to reduce its over-all environmental impact and energy consumption, the U.S. Army plans to apply NGEDAC technology in support of fixed facilities compressed air systems. Site assessment and demonstration results are presented in this paper.
Lin, M.; Aylor, S. W.; Van Ormer, H.
CFD Simulation and Analysis of the Combined Evaporative Cooling and Radiant Ceiling Air-conditioning System
Due to such disadvantages as large air duct and high energy consumption of the current all- outdoor air evaporative cooling systems used in the dry region of Northwest China, as well as the superiority of the ceiling cooling system in improving thermal comfort and saving energy, a combined system is presented in this paper. It combines an evaporative cooling system with ceiling cooling, in which the evaporative cooling system handles the entire latent load and one part of the sensible loads, and the ceiling cooling system deals with the other part of sensible loads in the air-conditioned zone, so that the condensation on radiant panels and the insufficiency of cooling capacity can be avoided. The cooling water at 18? used in the cooling coils of ceiling cooling system can be ground water, tap water or the cooled water from cooling towers in the summer. This new air-conditioning system and existing all- outdoor air evaporative cooling system are applied to a project in the city of Lanzhou. Energy consumption analysis of the building is carried out using the energy consumption code. Velocity and temperature distribution in the air-conditioned zone is computed using CFD. According to the results, the energy consumption and indoor human thermal comfort of both systems are then compared. It is concluded that the new system occupies less building space, reduces energy consumption, improves indoor human thermal comfort and saves initial investment.
Xiang, H.; Yinming, L.; Junmei, W.
Carbon Dioxide and Ionic Liquid Refrigerants: Compact, Efficient Air Conditioning with Ionic Liquid-Based Refrigerants
BEETIT Project: Notre Dame is developing an air-conditioning system with a new ionic liquid and CO2 as the working fluid. Synthetic refrigerants used in air conditioning and refrigeration systems are potent GHGs and can trap 1,000 times more heat in the atmosphere than CO2 alone�making CO2 an attractive alternative for synthetic refrigerants in cooling systems. However, operating cooling systems with pure CO2 requires prohibitively high pressures and expensive hardware. Notre Dame is creating a new fluid made of CO2 and ionic liquid that enables the use of CO2 at low pressures and requires minimal changes to existing hardware and production lines. This new fluid also produces no harmful emissions and can improve the efficiency of air conditioning systems� enabling new use of CO2 as a refrigerant in cooling systems.
Use of seawater for air conditioning at Waikiki Convention Center. Master's thesis
A large part of operating costs of a hotel in Hawaii is the cost of energy for air conditioning. Buildings can be constructed to use energy more efficiently by using many methods, however, some of these methods conflict with other concerns, aesthetics for example. Thus the process of designing and building an energy efficient hotel often involves trade-offs between energy efficiency and other objectives. The method proposed herein to reduce energy costs is to introduce seawater, pumped from the deep ocean at a temperature of approximately six degrees celsius, directly to heat exchangers which cool the chilled water circulating in the building air conditioning system. The energy required to run the system would be reduced to only the cost of the seawater pumps, the fans and controls. The savings would be in the operating costs of the seawater pumps versus the cost to the compressors of a conventional air conditioning system.
Williams, M.
Table HC15.7 Air-Conditioning Usage Indicators by Four Most Populated States, 2005
7 Air-Conditioning Usage Indicators by Four Most Populated States, 2005 7 Air-Conditioning Usage Indicators by Four Most Populated States, 2005 Total.................................................................................. 111.1 7.1 7.0 8.0 12.1 Do Not Have Cooling Equipment.................................... 17.8 1.8 Q Q 4.9 Have Cooling Equipment................................................. 93.3 5.3 7.0 7.8 7.2 Use Cooling Equipment.................................................. 91.4 5.3 7.0 7.7 6.6 Have Equipment But Do Not Use it................................ 1.9 Q N Q 0.6 Type of Air-Conditioning Equipment 1, 2 Central System............................................................. 65.9 1.1 6.4 6.4 5.4 Without a Heat Pump................................................. 53.5 1.1 3.5 5.7 4.9 With a Heat Pump......................................................
??An air?cycle air conditioning system, using a typical automotive turbocharger as the core of the system, was designed and tested. Effects on engine performance were� (more)
Forster, Christopher James
A Field Study on Residential Air Conditioning Peak Loads During Summer in College Station, Texas
Severe capacity problems are experienced by electric utilities during hot summer afternoons. Several studies have found that, in large part, electric peak loads can be attributed to residential airconditioning use. This air-conditioning peak depends primarily on two factors: (i) the manner in which the homeowner operates his air-conditioner during the hot summer afternoons, and (ii) the amount by which the air-conditioner has been over-designed. Whole-house and air-conditioner electricity use data at 15 minute time intervals have been gathered and analyzed for 8 residences during the summer of 1991, six of which had passed the College Station Good Cents tests. Indoor air temperatures were measured by a mechanical chart recorder, while a weather station located on the main campus of Texas A&M university provided the necessary climatic data, especially ambient temperature, relative humidity and solar radiation. The data were analysed to determine the extent to which air-conditioning over-sizing and homeowner intervention contributes to peak electricity use for newer houses in College Station, Texas.
Reddy, T. A.; Vaidya, S.; Griffith, L.; Bhattacharyya, S.; Claridge, D. E.
Theoretical Study of a Novel Control Method of VAV Air-conditioning System Based on MATLAB
The main purpose of this study is to put forward a novel nonlinear feedback control strategy on controlling indoor air temperature by variable air volume. A dynamic model of a typical room for a VAV air-conditioning system is established. The performance of the novel control strategy is investigated. Simulation of the controlling air temperature, on which the novel strategy is adopted, was carried out based on MATLAB in the VAV system. In order to show that the novel control strategy outperforms conventional PID control, a comparison is made between the performance of conventional PID and the novel nonlinear feedback control strategy. The results show that nonlinear feedback control strategy outperforms a conventional PID control system in terms of celerity, stability and other aspects.
Shi, Z.; Hu, S.; Wang, G.; Li, A.
Monitoring the Performance of a Residential Central Air Conditioner under Degraded Conditions on a Test Bench
This report presents the measured degradation in performance of a residential air conditioning system operating under degraded conditions. Experiments were conducted using a R-22 threeton split-type cooling system with a short-tube orifice expansion device. Results are presented here for a series of tests in which the various commonly occurring degraded conditions were simulated on a test bench. At present, very little information is available which quantifies the performance of a residential cooling system operating under degraded conditions. Degraded performance measurements can provide information which could help electric utilities evaluate the potential impact of systemwide maintenance programs. This report also discuss the development of a diagnostic procedure based on measurement of refrigerant and air side temperatures.
Palani, M.; O'Neal, D. L.; Haberl, J. S.
Demonstration of Air-Power-Assist Engine Technology for Clean Combustion and Direct Energy Recovery in Heavy Duty Application
The first phase of the project consists of four months of applied research, starting from September 1, 2005 and was completed by December 31, 2005. During this time, the project team heavily relied on highly detailed numerical modeling techniques to evaluate the feasibility of the APA technology. Specifically, (i) A GT-Power{sup TM}engine simulation model was constructed to predict engine efficiency at various operating conditions. Efficiency was defined based on the second-law thermodynamic availability. (ii) The engine efficiency map generated by the engine simulation was then fed into a simplified vehicle model, which was constructed in the Matlab/Simulink environment, to predict fuel consumption of a refuse truck on a simple collection cycle. (iii) Design and analysis work supporting the concept of retrofitting an existing Sturman Industries Hydraulic Valve Actuation (HVA) system with the modifications that are required to run the HVA system with Air Power Assist functionality. A Matlab/Simulink model was used to calculate the dynamic response of the HVA system. Computer aided design (CAD) was done in Solidworks for mechanical design and hydraulic layout. At the end of Phase I, 11% fuel economy improvement was predicted. During Phase II, the engine simulation group completed the engine mapping work. The air handling group made substantial progress in identifying suppliers and conducting 3D modelling design. Sturman Industries completed design modification of the HVA system, which was reviewed and accepted by Volvo Powertrain. In Phase II, the possibility of 15% fuel economy improvement was shown with new EGR cooler design by reducing EGR cooler outlet temperature with APA engine technology from Air Handling Group. In addition, Vehicle Simulation with APA technology estimated 4 -21% fuel economy improvement over a wide range of driving cycles. During Phase III, the engine experimental setup was initiated at VPTNA, Hagerstown, MD. Air Handling system and HVA system were delivered to VPTNA and then assembly of APA engine was completed by June 2007. Functional testing of APA engine was performed and AC and AM modes testing were completed by October 2007. After completing testing, data analysis and post processing were performed. Especially, the models were instrumental in identifying some of the key issues with the experimental HVA system. Based upon the available engine test results during AC and AM modes, the projected fuel economy improvement over the NY composite cycle is 14.7%. This is close to but slightly lower than the originally estimated 18% from ADVISOR simulation. The APA project group demonstrated the concept of APA technology by using simulation and experimental testing. However, there are still exists of technical challenges to meet the original expectation of APA technology. The enabling technology of this concept, i.e. a fully flexible valve actuation system that can handle high back pressure from the exhaust manifold is identified as one of the major technical challenges for realizing the APA concept.
Hyungsuk Kang; Chun Tai
Corrosion Behavior of Interconnect Candidate Alloys under Air//Simulated Reformate Dual Exposure Conditions
Metallic interconnects in solid oxide fuel cell (SOFC) stacks, perform in a very challenging dual environment, as they are simultaneously exposed to a reducing fuel (either hydrogen or a hydrocarbon fuel) on one side and air on the other side at elevated temperatures. Thus candidate metals or alloys for the interconnect applications must demonstrate excellent surface stability under the SOFC operating conditions. Following previous studies which led to an improved understanding of the oxidation/corrosion behavior of metals and alloys under air/hydrogen dual exposure conditions, PNNL recently investigated the behavior of Fe-Cr and Ni-Cr base interconnect candidate alloys in an air/simulated reformate dual environment. This paper reports and discusses the findings of this work.
Yang, Z Gary; Xia, Gordon; Stevenson, Jeffry W.; Singh, Prabhakar
Innovative Evaporative and Thermally Activated Technologies Improve Air Conditioning, The Spectrum of Clean Energy Innovation (Fact Sheet)
Innovative Evaporative and Innovative Evaporative and Thermally Activated Technologies Improve Air Conditioning Researchers at the National Renewable Energy Laboratory (NREL) invented a breakthrough technology that improves air conditioning in a novel way-with heat. NREL combined desiccant materials, which remove moisture from the air using heat, and advanced evaporative technologies to develop a cooling unit that uses 90% less electricity and up to 80% less total energy than traditional air conditioning (AC). This solution, called the desiccant enhanced evaporative air conditioner (DEVap), also controls humidity more effectively to improve the comfort of people in buildings. Desiccants are an example of a thermally activated technology (TAT) that relies on heat instead
Investigation of air supply conditions in the room of a B11type gas appliance
In Hungary, the prevalently used "B11" type gas appliances equipped with atmospheric burner and they have a draught hood beyond the outlet of the appliance. For the appropriate adjustment of the gas boiler to the conditions of the building, ... Keywords: CFD method, air supply, chimney, design requirements, gas appliances, numerical modelling
Lajos Barna; R�bert Goda
A heuristic predictive logic controller applied to hybrid solar air conditioning plant
This paper shows the development of a heuristic predictive logic controller (HPLoC) applied to a solar air conditioning plant. The plant uses two energy sources, solar and gas, in order to warm up the water. The hot water feeds a single-effect absorption ...
Darine Zambrano; Winston Garc�a-Gab�n; Eduardo F. Camacho
Proceedings of the 1993 non-fluorocarbon insulation, refrigeration and air conditioning technology workshop
Sessions included: HFC blown polyurethanes, carbon dioxide blown foam and extruded polystyrenes, plastic foam insulations, evacuated panel insulation, refrigeration and air conditioning, absorption and adsorption and stirling cycle refrigeration, innovative cooling technologies, and natural refrigerants. Selected papers have been indexed separately for inclusion in the Energy Science and Technology Database.
Long-Range Transport of Air Pollution under Light Gradient Wind Conditions
The long-range transport of air pollution on clew days under light gradient wind conditions is investigated from an analysis of all days with high oxidant concentrations in 1979 at locations in central Japan that are far from pollutant sources. ...
Hidemi Kurita; Kazutoshi Sasaki; Hisao Muroga; Hiromasa Ueda; Shinji Wakamatsu
SOLERAS - Saudi University Solar Cooling Laboratories Project: University of Riyadh. Solar air conditioning. Final report
Research on solar air conditioning at the University of Riyadh in Riyhadh, Saudi Arabia is presented. Topics relevant to the university's proposed solar cooling laboratory are discussed: absorption systems and various contingencies, photovoltaic solar collectors and thermoelectric elements, measuring instruments, solar radiation measurement and analysis, laboratory specifications, and decision theories. Dual cycle computations and equipment specifications are included among the appendices.
Discussion of Air-Conditioning Energy-Savings in Hot-Summer and Cold-Winter Regions
Introducing several kinds of air-conditioning systems energy conservation measures, and according to the climate of the hot-summer and cold-winter region in China, this paper puts forward an overall conception for air-conditioning energy-savings at this area. Namely, we may use the combination of evaporative cooling, dehumidifier and mechanical cooling to save energy for air-conditioning.
Zheng, W.; Gong, F.; Lou, X.; Cheng, J.
Total environmental warming impact (TEWI) calculations for alternative automative air-conditioning systems
The Montreal Protocol phase-out of chlorofluorocarbons (CFCs) has required manufacturers to develop refrigeration and air-conditioning systems that use refrigerants that can not damage stratospheric ozone. Most refrigeration industries have adapted their designs to use hydrochlorofluorocarbon (HCFC) or hydrofluorocarbon (HFC) refrigerants; new automobile air- conditioning systems use HFC-134a. These industries are now being affected by scientific investigations of greenhouse warming and questions about the effects of refrigerants on global warming. Automobile air-conditioning has three separate impacts on global warming; (1) the effects of refrigerant inadvertently released to the atmosphere from accidents, servicing, and leakage; (2) the efficiency of the cooling equipment (due to the emission of C0{sub 2} from burning fuel to power the system); and (3) the emission of C0{sub 2} from burning fuel to transport the system. The Total Equivalent Warming Impact (TEWI) is an index that should be used to compare the global warming effects of alternative air-conditioning systems because it includes these contributions from the refrigerant, cooling efficiency, and weight. This paper compares the TEWI of current air-conditioning systems using HFC-134a with that of transcritical vapor compression system using carbon dioxide and systems using flammable refrigerants with secondary heat transfer loops. Results are found to depend on both climate and projected efficiency of C0{sub 2}systems. Performance data on manufacturing prototype systems are needed to verify the potential reductions in TEWI. Extensive field testing is also required to determine the performance, reliability, and ``serviceability`` of each alternative to HFC-134a to establish whether the potential reduction of TEWI can be achieved in a viable consumer product.
Sand, J.R.; Fischer, S.K.
Air Conditioning, & Electric Power Machinery 29(1): 1-4 Solutions for Summer Electric Power Shortages: DemandUSA Solutions for summer electric power shortages: Demand
Application of the VRV Air-Conditioning System Heat Recovery Series in Interior Zone and Analysis of its Energy Saving
To reduce the energy consumption of air conditioning systems, we can use the VRV air conditioning system to supply cold loads in the winter for rooms in the construction inner zone where cold loads need to be supplied. The VRV air-conditioning system of variable frequency technology can achieve the effect of energy conservation. In this article, we analyze the application of the VRV air conditioning system heat recovery series in the construction inner zone and its energy saving characteristics via a project example.
Zhang, Q.; Li, D.; Zhang, J.
Start-Up of Air Conditioning Systems After Periods of Shutdown (Humidity Considerations)
In many cases the single most important energy conservation measure that can be taken is to turn equipment off when it is not needed. In the case of air conditioning, this generally means turning it off when occupants leave and turning it back on in time to have the space comfortable when they return. In humid climates special problems are often encountered when a system is restarted after a period of shutdown. The temperature and humidity in the space rises during the period of shutdown. Unfortunately the latent load required to bring the space back to comfort conditions is usually much higher than the sensible load. Most methods of control are ill suited for this duty. This paper examines the response of various types of air conditioning systems during this recovery period and makes recommendations for system designers.
Todd, T. R.
Selection of Light Duty Truck Engine Air Systems Using Virtual Lab Tests
An integrated development approach using seasoned engine technology methodologies, virtual lab parametric investigations, and selected hardware verification tests reflects today's state-of-the-art R&D trends. This presentation will outline such a strategy. The use of this ''Wired'' approach results in substantial reduction in the development cycle time and hardware iterations. An example showing the virtual lab application for a viable design of the air-exhaust-turbocharger system of a light duty truck engine for personal transportation will be presented.
Zhang, Houshun
Increased Efficiency in SI Engine with Air Replaced by Oxygen in Argon Mixture
Basic engine thermodynamics predicts that spark ignited engine efficiency is a function of both the compression ratio of the engine and the specific heat ratio of the working fluid. In practice the compression ratio of the engine is often limited due to knock. Both higher specific heat ratio and higher compression ratio lead to higher end gas temperatures and increase the likelihood of knock. In actual engine cycles, heat transfer losses increase at higher compression ratios and limit efficiency even when the knock limit is not reached. In this paper we investigate the role of both the compression ratio and the specific heat ratio on engine efficiency by conducting experiments comparing operation of a single-cylinder variable-compression-ratio engine with both hydrogen-air and hydrogen-oxygen-argon mixtures. For low load operation it is found that the hydrogen-oxygen-argon mixtures result in higher indicated thermal efficiencies. Peak efficiency for the hydrogen-oxygen-argon mixtures is found at compression ratio 5.5 whereas for the hydrogen-air mixture with an equivalence ratio of 0.24 the peak efficiency is found at compression ratio 13. We apply a three-zone model to help explain the effects of specific heat ratio and compression ratio on efficiency. Operation with hydrogen-oxygen-argon mixtures at low loads is more efficient because the lower compression ratio results in a substantially larger portion of the gas to reside in the adiabatic core rather than in the boundary layer and in the crevices, leading to less heat transfer and more complete combustion.
Killingsworth, N J; Rapp, V H; Flowers, D L; Aceves, S M; Chen, J; Dibble, R
Research on Thermal Properties in a Phase Change Wallboard Room Based on Air Conditioning Cold Storage
After comparing the thermal performance parameters of an ordinary wall room to a phase change wall (PCW) room, we learn that phase change wallboard affects the fluctuation of temperature in air-conditioning room in the summer. We built a PCW room and an ordinary wall room, which are cooled by an air-conditioner. We used differential scanning calorimetry (DSC) to test the temperature field and heat flow fluctuation in these rooms. Through analyzing the data tested, we found that the mean temperature of PCW is lower than that of ordinary wall room by 1 to 2?, and PCW can lower the heat flow by 4.6W/m2. Combining phase change material with the building envelope can lower the indoor temperature, make the room thermally comfortable, and cut down the turn-on-and-off frequency of the air-conditioner and the primary investment and operating costs. It alleviates the urgent need for electricity.
Feng, G.; Li, W.; Chen, X.
Comparative Study Between Air-Cooled and Water-Cooled Condensers of the Air-Conditioning Systems
The weather in Kuwait is very dry where the dry-bulb temperature exceeds the wet-bulb temperature more than 20oC in most of the summer months. Thus, the air-conditioning (A/C) system with the water-cooled (WC) condensers is expected to perform more efficiently than with the air-cooled (AC) condensers. This fact was behind the idea of a field study conducted in one of the major hospital in Kuwait during a summer season to investigate the performance of WC and AC systems in terms of peak power and energy consumptions. The cooling capacities for WC and AC systems were 373 and 278 tons-of- refrigeration, respectively. It was found that for the same cooling production, the peak power demand and the daily energy consumption of the WC system were 45 and 32% less than that of the AC system, respectively. The maximum reduction in the power demand coincided with the peak power demand period of the utilities i.e. between 14:00 and 17:00 hr, thereby offering a maximum advantage of peak power saving.
Maheshwari, G. P.; Mulla Ali, A. A.
Addition of inexpensive solar air-heaters to a pre-engineered metal building. Final report
At Mississippi State University a research project was begun in 1976 to investigate the use of site-built solar collectors for heating air in poultry houses. The purpose of this work was to design and test a functional air heater solar collector which would be inexpensive to construct and acceptable to poultry producers. The results reported are an extension of the original concept. The basic concept is to use a pre-engineered metal building for the structure and incorporate the solar air heaters as an integral part of the south facing wall of the building. The outer skin of the building is used as the absorber plate for the collctors. Construction and testing of the solar collectors and heat storage systems are discussed, and the performance characteristics of the site-built solar collectors are described. (WHK)
Forbes, R E; McClendon, R W
Energy Performance Comparison of Heating and Air Conditioning Systems for Multi-Family Residential Buildings
The type of heating, ventilation and air conditioning (HVAC) system has a large impact on the heating and cooling energy consumption in multifamily residential buildings. This paper compares the energy performance of three HVAC systems: a direct expansion (DX) split system, a split air source heat pump (ASHP) system, and a closed-loop water source heat pump (WSHP) system with a boiler and an evaporative fluid cooler as the central heating and cooling source. All three systems use gas furnace for heating or heating backup. The comparison is made in a number of scenarios including different climate conditions, system operation schemes and applicable building codes. It is found that with the minimum code-compliant equipment efficiency, ASHP performs the best among all scenarios except in extremely code climates. WSHP tends to perform better than the split DX system in cold climates but worse in hot climates.
Wang, Weimin; Zhang, Jian; Jiang, Wei; Liu, Bing
Influencing Factors on Energy Consumption of Air Conditioning System in Railway Passenger Station Based on Orthogonal Experiment
Orthogonal experiment was used to analyze the energy consumption of air conditioning system, which belongs to four typical passenger stations in four regions, including severe cold region, cold region, hot summer and cold winter region, hot summer and ... Keywords: Railway Passenger Station, Orthogonal Experiment, Air Conditioning Energy Consumption, Energy Conservation
Weiwu Ma; Liqing Li; Suoying He; Jia Cheng; Guijie Huang; Chenn Q. Zhou
Experimental and computational study of soot formation under diesel engine conditions
Past research has shown that during diesel combustion, soot is formed in local premixed fuel-rich regions. This project focuses on the fundamentals soot formation under fuel-rich conditions similar to those in diesel engine ...
Kitsopanidis, Ioannis, 1975-
Impact of cool storage air-conditioning in commercial sector on power system operation in Thailand
The results are presented from an investigation into the potential application for cool storage air-conditioning, and the resultant beneficial impact on power system operation in Thailand is discussed. Field assessment through interviews with decision makers in the identified customer groups produces results that show good potential for cool storage application. Results from a computer program used to calculate power production cost and other characteristics show that substantial benefits would also accrue to the generating utility.
Surapong, C.; Bundit, L. [Asian Inst. of Tech., Bangkok (Thailand)
Exploratory Research on MEMS Technology for Air-Conditioning and Heat-Pumps
Multiple refrigerant channels are essential for improving system efficiency in refrigeration and air-conditioning systems. A study was conducted to study the use of micro-electrical-mechanical- systems (MEMS) and micro device technologies to improve current vapor compression refrigeration cycles. The first step toward realizing this goal, and the focus of this report, is to determine how to better control multi-channel evaporators by reducing refrigerant maldistribution among channels.
Performance Assessment of a Variable Refrigerant Flow Heat Pump Air Conditioning System
Variable refrigerant flow (VRF) technology uses smart integrated controls, variable speed drives, and refrigerant piping to provide energy efficiency, flexible operation, ease of installation, low noise, zone control, and comfort through all-electric technology. This report describes and documents the construction, performance, and application of a heat pump air conditioning system that uses VRF technology8212the Daikin VRV system. This variable refrigerant volume (VRV) system is manufactured by Daikin I...
The Earth-Coupled or Geothermal Heat Pump Air Conditioning System
As utility costs have risen despite political campaign promises and energy conserving measures implemented by the utility companies such as alternative fuel use (coal and nuclear), co-generation, etc., homeowners have begun to search for effective methods of reducing their electricity bills. In some cases homeowners are faced with utility bills That are approaching the cost of their mortgage payments. For those with fixed incomes, such as the elderly or those looking forward to retirement in the near future, this has become an alarming reality. Virtually every homeowner would like to reduce his utility bill but the question is, what items should he address in order to have a significant impact on his electricity costs? According to Houston Lighting h Power Company, 50% of an electricity bill can be attributed to the air conditioning system, and another 15-20% to the hot water heating system. Therefore, to dramatically reduce utility costs one should look first at these two "energy gulpers" and next at proper home insulation, window coverings, etc. The other electrical appliances in the home use relatively minor amounts of electricity compared to the air conditioning and hot water heating system. This paper will describe the geothermal heat pump and the desuperheater as the latest developments in energy efficient air conditioning and water heating.
Wagers, H. L.; Wagers, M. C.
Comparison of global warming impacts of automobile air-conditioning concepts
The global warming impacts of conventional vapor compression automobile air conditioning using HFC-134a are compared with the potential impacts of four alternative concepts. Comparisons are made on the basis of total equivalent warming impact (TEWI) which accounts for the effects of refrigerant emissions, energy use to provide comfort cooling, and fuel consumed to transport the weight of the air conditioning system. Under the most favorable assumptions on efficiency and weight, transcritical compression using CO{sub 2} as the refrigerant and adsorption cooling with water and zeolite beds could reduce TEWI by up to 18%rlative to HFC-134a compression air conditioning. Other assumptions on weight and efficiency lead to significant increases in TEWI relative to HFC-134a, and it is impossible to determine which set of assumptios is valid from existing data, Neither Stirling cycle or thermoelectric cooling will reduce TEWI relative to EFC-134a. Brief comments are also made concerning technical barriers that must be overcome for succesful development of the new technologies.
Table HC6.7 Air-Conditioning Usage Indicators by Number of Household Members, 2005
7 Air-Conditioning Usage Indicators by Number of Household Members, 2005 7 Air-Conditioning Usage Indicators by Number of Household Members, 2005 Total........................................................................ 111.1 30.0 34.8 18.4 15.9 12.0 Do Not Have Cooling Equipment.......................... 17.8 5.4 5.3 2.7 2.5 2.0 Have Cooling Equipment...................................... 93.3 24.6 29.6 15.7 13.4 10.0 Use Cooling Equipment....................................... 91.4 24.0 29.1 15.5 13.2 9.7 Have Equipment But Do Not Use it...................... 1.9 0.6 0.5 Q 0.2 0.4 Type of Air-Conditioning Equipment 1, 2 Central System................................................... 65.9 15.3 22.6 10.7 9.9 7.3 Without a Heat Pump....................................... 53.5 12.5 17.9 8.7 8.2 6.3 With a Heat Pump............................................ 12.3
Table HC9.6 Air Conditioning Characteristics by Climate Zone, 2005
6 Air Conditioning Characteristics by Climate Zone, 2005 6 Air Conditioning Characteristics by Climate Zone, 2005 Million U.S. Housing Units Total......................................................................... 111.1 10.9 26.1 27.3 24.0 22.8 Do Not Have Cooling Equipment........................... 17.8 3.2 4.7 3.6 5.5 0.9 Have Cooling Equipment........................................ 93.3 7.7 21.4 23.7 18.5 21.9 Use Cooling Equipment......................................... 91.4 7.6 21.0 23.4 17.9 21.7 Have Equipment But Do Not Use it........................ 1.9 Q 0.4 0.4 0.6 0.3 Air-Conditioning Equipment 2, 3 Central System...................................................... 65.9 4.8 12.3 15.1 14.9 18.7 Without a Heat Pump......................................... 53.5 4.7 11.5 11.6 12.3 13.6 With a Heat Pump..............................................
The Histoty of Ventilation and Air Conditioning is CERN Up to Date with the latest Technological Developments?
The invention of ventilation cannot be ascribed to a certain date. It started with simple aeration when man brought fire into his abode and continued through different stages including air cooling using ice to finally arrive at the time when ventilation and air conditioning has become an essential part of our life and plays an important role in human evolution. This paper presents the history of ventilation and air conditioning, explains the key constraints over the centuries, and shows its influence on everyday life. Some examples of previous air-conditioning plants are described and different approaches to the way of calculation of ventilation systems discussed. It gives an overview of the Heating, Ventilation and Air Conditioning (HVAC) installations at CERN and points out their particularities. It also compares them with the latest technological developments in the field as well as showing the new trends that are being applied at CERN.
K�hnl-Kinel, J
The Oklahoma Field Test: Air-conditioning electricity savings from standard energy conservation measures, radiant barriers, and high-efficiency window air conditioners
A field test Involving 104 houses was performed in Tulsa, Oklahoma, to measure the air-conditioning electricity consumption of low-income houses equipped with window air conditioners, the reduction in this electricity consumption attributed to the installation of energy conservation measures (ECMS) as typically installed under the Oklahoma Weatherization Assistance Program (WAP), and the reduction achieved by the replacement of low-efficiency window air conditioners with high-efficiency units and the installation of attic radiant barriers. Air-conditioning electricity consumption and indoor temperature were monitored weekly during the pre-weatherization period (June to September 1988) and post-weatherization period (May to September 1989). House energy consumption models and regression analyses were used to normalize the air-conditioning electricity savings to average outdoor temperature conditions and the pre-weatherization indoor temperature of each house. The following conclusions were drawn from the study: (1) programs directed at reducing air-conditioning electricity consumption should be targeted at clients with high consumption to improve cost effectiveness; (2) replacing low-efficiency air conditioners with high-efficiency units should be considered an option in a weatherization program directed at reducing air-conditioning electricity consumption; (3) ECMs currently being installed under the Oklahoma WAP (chosen based on effectiveness at reducing space-heating energy consumption) should continue to be justified based on their space-heating energy savings potential only; and (4) attic radiant barriers should not be included in the Oklahoma WAP if alternatives with verified savings are available or until further testing demonstrates energy savings or other benefits in this typo of housing.
Ternes, M.P.; Levins, W.P.
Cascade Reverse Osmosis Air Conditioning System: Cascade Reverse Osmosis and the Absorption Osmosis Cycle
BEETIT Project: Battelle is developing a new air conditioning system that uses a cascade reverse osmosis (RO)-based absorption cycle. Analyses show that this new cycle can be as much as 60% more efficient than vapor compression, which is used in 90% of air conditioners. Traditional vapor-compression systems use polluting liquids for a cooling effect. Absorption cycles use benign refrigerants such as water, which is absorbed in a salt solution and pumped as liquid�replacing compression of vapor. The refrigerant is subsequently separated from absorbing salt using heat for re-use in the cooling cycle. Battelle is replacing thermal separation of refrigerant with a more efficient reverse osmosis process. Research has shown that the cycle is possible, but further investment will be needed to reduce the number of cascade reverse osmosis stages and therefore cost.
LiCl Dehumidifier LiBr absorption chiller hybrid air conditioning system with energy recovery
This invention relates to a hybrid air conditioning system that combines a solar powered LiCl dehumidifier with a LiBr absorption chiller. The desiccant dehumidifier removes the latent load by absorbing moisture from the air, and the sensible load is removed by the absorption chiller. The desiccant dehumidifier is coupled to a regenerator and the desiccant in the regenerator is heated by solar heated hot water to drive the moisture therefrom before being fed back to the dehumidifier. The heat of vaporization expended in the desiccant regenerator is recovered and used to partially preheat the driving fluid of the absorption chiller, thus substantially improving the overall COP of the hybrid system.
Ko, Suk M. (Huntsville, AL)
Vehicle Air- Vehicle Air- Conditioning on Fuel Economy, Tailpipe Emissions, and Electric Vehicle Range Preprint September 2000 * NREL/CP-540-28960 R. Farrington and J. Rugh To Be Presented at the Earth Technologies Forum Washington, D.C. October 31, 2000 National Renewable Energy Laboratory 1617 Cole Boulevard Golden, Colorado 80401-3393 NREL is a U.S. Department of Energy Laboratory Operated by Midwest Research Institute * * * * Battelle * * * * Bechtel Contract No. DE-AC36-99-GO10337 NOTICE The submitted manuscript has been offered by an employee of the Midwest Research Institute (MRI), a contractor of the US Government under Contract No. DE-AC36-99GO10337. Accordingly, the US Government and MRI retain a nonexclusive royalty-free license to publish or reproduce the published
Proposal for a Vehicle Level Test Procedure to Measure Air Conditioning Fuel Use
The air-conditioning (A/C) compressor load significantly impacts the fuel economy of conventional vehicles and the fuel use/range of plug-in hybrid electric vehicles (PHEV). A National Renewable Energy Laboratory (NREL) vehicle performance analysis shows the operation of the air conditioner reduces the charge depletion range of a 40-mile range PHEV from 18% to 30% in a worst case hot environment. Designing for air conditioning electrical loads impacts PHEV and electric vehicle (EV) energy storage system size and cost. While automobile manufacturers have climate control procedures to assess A/C performance, and the U.S. EPA has the SCO3 drive cycle to measure indirect A/C emissions, there is no automotive industry consensus on a vehicle level A/C fuel use test procedure. With increasing attention on A/C fuel use due to increased regulatory activities and the development of PHEVs and EVs, a test procedure is needed to accurately assess the impact of climate control loads. A vehicle thermal soak period is recommended, with solar lamps that meet the SCO3 requirements or an alternative heating method such as portable electric heaters. After soaking, the vehicle is operated over repeated drive cycles or at a constant speed until steady-state cabin air temperature is attained. With this method, the cooldown and steady-state A/C fuel use are measured. This method can be run at either different ambient temperatures to provide data for the GREEN-MAC-LCCP model temperature bins or at a single representative ambient temperature. Vehicles with automatic climate systems are allowed to control as designed, while vehicles with manual climate systems are adjusted to approximate expected climate control settings. An A/C off test is also run for all drive profiles. This procedure measures approximate real-world A/C fuel use and assess the impact of thermal load reduction strategies.
Rugh, J. P.
Effects of engineering controls on radioactive air emissions from the Los Alamos Neutron Science Center
Under federal regulations set forth in 40 CFR 61, releases of radioactive airborne effluents from a Department of Energy facility must be limited so that no member of the public receives more than 0. IO miflisievert (IO milhrem) effective dose equivalent annually. At Los Alamos National Laboratory (LANL), the Los Alamos Neutron Science Center (LANSCE) has implemented engineering controls to ensure that emissions remain below this limit. At the accelerator beam stop, a delay line was constructed to delay exhaust air releases, and thereby allow for decay of any radioactivity prior to release. Also, an air scrubber was built at the beam stop to remove excess water, acids, triti@ and carbon dioxide from the air stream. This thesis describes the effectiveness of these emissions control efforts. Using a flow-through ionization chamber and high-purity germanium (HPGE) detector, the delay line was shown to reduce overall facility emissions by 29%. The scrubber effectiveness at removing tritium was found by collecting grab samples of the air stream on silica gel, both upstream and downstream of the scrubber. Results of liquid scintillation analysis show the tritium removal effectiveness to be greater than 95%. Removal of carbon-I I was determined by two methods. First, air samples upstream and downstream of the scrubber were collected on a carbon dioxide absorber and analyzed with a sodium iodide detector. The second method used a bench-top model scrubbing system to analyze scrubber performance with an BPGE detector. Different scenarios were examined with this model system, including varying the pH of the scrubber water and using catalytic conversion to convert all carbon in the air to carbon dioxide. The highest removal effectiveness of the model system was greater than 95%, under high pH and complete conversion of all carbon forms to C02-
Fuehne, David Patrick
The Experimentation System Design and Experimental Study of the Air-Conditioning by Desiccant Type Using Solar Energy
Using a special solar air heater to gain heat power for regenerating an adsorption desiccant wheel made by composite silica gel, a desiccant air-conditioning experimentation system was designed and manufactured. Combining the advantage of measure and control by �PLC� and the software of �Kingview�, the whole year's operating results of this system was tested and analysed. The results indicate this system can keep the indoor air temperature range at 26�2�C and the relative humidity range being 50-70% under the low electricity cost on the whole year in the south of China region when the special solar air heater can offer flux air heating up to 60�C. In this paper some ideas are offered in order to facilitate the availability for air-conditioning using low grade energy, for example, solar energy and surplus or waste heat energy in the industrial process.
Zhuo, X.; Ding, J.; Yang, X.; Chen, S.; Yang, J.
Fuel-Free Compressed-Air Energy Storage: Fuel-Free, Ubiquitous Compressed-Air Energy Storage and Power Conditioning
GRIDS Project: General Compression has developed a transformative, near-isothermal compressed air energy storage system (GCAES) that prevents air from heating up during compression and cooling down during expansion. When integrated with renewable generation, such as a wind farm, intermittent energy can be stored in compressed air in salt caverns or pressurized tanks. When electricity is needed, the process is reversed and the compressed air is expanded to produce electricity. Unlike conventional compressed air energy storage (CAES) projects, no gas is burned to convert the stored high-pressure air back into electricity. The result of this breakthrough is an ultra-efficient, fully shapeable, 100% renewable and carbon-free power product. The GCAES� system can provide high quality electricity and ancillary services by effectively integrating renewables onto the grid at a cost that is competitive with gas, coal and nuclear generation.
Solutions for Summer Electric Power Shortages: Demand Response andits Applications in Air Conditioning and Refrigerating Systems
Demand response (DR) is an effective tool which resolves inconsistencies between electric power supply and demand. It further provides a reliable and credible resource that ensures stable and economical operation of the power grid. This paper introduces systematic definitions for DR and demand side management, along with operational differences between these two methods. A classification is provided for DR programs, and various DR strategies are provided for application in air conditioning and refrigerating systems. The reliability of DR is demonstrated through discussion of successful overseas examples. Finally, suggestions as to the implementation of demand response in China are provided.
How refrigeration, heating, ventilation, and air conditioning service technicians learn from troubleshooting (Dissertation ABstract)
The purpose of this study was to understand how refrigeration, heating, ventilation, and air conditioning (RHVAC) service technicians (techs) learned from troubleshooting. This understanding resulted in instructional and curricular strategies designed to help community colleges prepare vocational students to learn more effectively from informal workplace learning. RHVAC techs were studied because they increasingly learn their trade skills through a combination of formal schooling and informal workplace learning, though many still learn their trade almost exclusively in the workplace. Even those with formal training require considerable workplace experience to become fully competent. Troubleshooting is a major job function for RHVAC service techs, and troubleshooting
Denis F. H. Green
Desiccant solar air conditioning in tropical climates: II-field testing in Guadeloupe
This paper presents the results of the experimental investigation of a solar desiccant air conditioning device exposed to the sun in Guadeloupe to test that adaptability of a silicagel compact bed, the most simple technology, in a tropical climate. It has been shown that it is possible to make use of solar flat plate collectors with a balancing water tank, to produce heat for the regeneration of a solid desiccant as silicagel, with solar energy. Second, the compact bed system proposed gives the foreseen cooling power, but considerable losses appear, particularly in the sorption process, which is not close enough to the reversible adiabatic one.
Dupont, M.; Celestine, B.; Beghin, B. (Solar Energy Lab., Pointe-a-Pitre (Guadeloupe))
Numerical Simulations of Air�Sea Interaction under High Wind Conditions Using a Coupled Model: A Study of Hurricane Development
In this study, a coupled atmosphere�ocean wave modeling system is used to simulate air�sea interaction under high wind conditions. This coupled modeling system is made of three well-tested model components: The Pennsylvania State University�...
J-W. Bao; J. M. Wilczak; J-K. Choi; L. H. Kantha
The Impact of Climate Change on Air Quality�Related Meteorological Conditions in California. Part I: Present Time Simulation Analysis
This study investigates the impacts of climate change on meteorology and air quality conditions in California by dynamically downscaling Parallel Climate Model (PCM) data to high resolution (4 km) using the Weather Research and Forecast (WRF) ...
Zhan Zhao; Shu-Hua Chen; Michael J. Kleeman; Mary Tyree; Dan Cayan
"Table HC15.6 Air Conditioning Characteristics by Four Most Populated States, 2005"
6 Air Conditioning Characteristics by Four Most Populated States, 2005" 6 Air Conditioning Characteristics by Four Most Populated States, 2005" " Million U.S. Housing Units" ,"U.S. Housing Units (millions)","Four Most Populated States" "Air Conditioning Characteristics",,"New York","Florida","Texas","California" "Total",111.1,7.1,7,8,12.1 "Do Not Have Cooling Equipment",17.8,1.8,"Q","Q",4.9 "Have Cooling Equipment",93.3,5.3,7,7.8,7.2 "Use Cooling Equipment",91.4,5.3,7,7.7,6.6 "Have Equipment But Do Not Use it",1.9,"Q","N","Q",0.6 "Air-Conditioning Equipment1, 2 " "Central System",65.9,1.1,6.4,6.4,5.4
"Table HC11.7 Air-Conditioning Usage Indicators by Northeast Census Region, 2005"
7 Air-Conditioning Usage Indicators by Northeast Census Region, 2005" 7 Air-Conditioning Usage Indicators by Northeast Census Region, 2005" " Million U.S. Housing Units" ,,"Northeast Census Region" ,"U.S. Housing Units (millions)" ,,,"Census Division" ,,"Total Northeast" "Air Conditioning Usage Indicators",,,"Middle Atlantic","New England" "Total",111.1,20.6,15.1,5.5 "Do Not Have Cooling Equipment",17.8,4,2.4,1.7 "Have Cooling Equipment",93.3,16.5,12.8,3.8 "Use Cooling Equipment",91.4,16.3,12.6,3.7 "Have Equipment But Do Not Use it",1.9,0.3,"Q","Q" "Type of Air-Conditioning Equipment1, 2" "Central System",65.9,6,5.2,0.8 "Without a Heat Pump",53.5,5.5,4.8,0.7
"Table HC15.7 Air-Conditioning Usage Indicators by Four Most Populated States, 2005"
7 Air-Conditioning Usage Indicators by Four Most Populated States, 2005" 7 Air-Conditioning Usage Indicators by Four Most Populated States, 2005" " Million U.S. Housing Units" ,"Housing Units (millions)","Four Most Populated States" "Air Conditioning Usage Indicators",,"New York","Florida","Texas","California" "Total",111.1,7.1,7,8,12.1 "Do Not Have Cooling Equipment",17.8,1.8,"Q","Q",4.9 "Have Cooling Equipment",93.3,5.3,7,7.8,7.2 "Use Cooling Equipment",91.4,5.3,7,7.7,6.6 "Have Equipment But Do Not Use it",1.9,"Q","N","Q",0.6 "Type of Air-Conditioning Equipment1, 2" "Central System",65.9,1.1,6.4,6.4,5.4
"Table HC10.7 Air-Conditioning Usage Indicators by U.S. Census Region, 2005"
7 Air-Conditioning Usage Indicators by U.S. Census Region, 2005" 7 Air-Conditioning Usage Indicators by U.S. Census Region, 2005" " Million U.S. Housing Units" ,"Housing Units (millions)","U.S. Census Region" "Air Conditioning Usage Indicators",,"Northeast","Midwest","South","West" "Total",111.1,20.6,25.6,40.7,24.2 "Do Not Have Cooling Equipment",17.8,4,2.1,1.4,10.3 "Have Cooling Equipment",93.3,16.5,23.5,39.3,13.9 "Use Cooling Equipment",91.4,16.3,23.4,38.9,12.9 "Have Equipment But Do Not Use it",1.9,0.3,"Q",0.5,1 "Type of Air-Conditioning Equipment1, 2" "Central System",65.9,6,17.3,32.1,10.5 "Without a Heat Pump",53.5,5.5,16.2,23.2,8.7
"Table HC13.7 Air-Conditioning Usage Indicators by South Census Region, 2005"
7 Air-Conditioning Usage Indicators by South Census Region, 2005" 7 Air-Conditioning Usage Indicators by South Census Region, 2005" " Million U.S. Housing Units" ,,"South Census Region" ,"U.S. Housing Units (millions)" ,,,"Census Division" ,,"Total South" "Air Conditioning Usage Indicators",,,"South Atlantic","East South Central","West South Central" "Total",111.1,40.7,21.7,6.9,12.1 "Do Not Have Cooling Equipment",17.8,1.4,0.8,0.2,0.3 "Have Cooling Equipment",93.3,39.3,20.9,6.7,11.8 "Use Cooling Equipment",91.4,38.9,20.7,6.6,11.7 "Have Equipment But Do Not Use it",1.9,0.5,"Q","Q","Q" "Type of Air-Conditioning Equipment1, 2"
Transformation of Sulfur Species during Steam/Air Regeneration on a Ni Biomass Conditioning Catalyst
Sulfur K-edge XANES identified transformation of sulfides to sulfates during combined steam and air regeneration on a Ni/Mg/K/Al2O3 catalyst used to condition biomass-derived syngas. This catalyst was tested over multiple reaction/regeneration/reduction cycles. Postreaction catalysts showed the presence of sulfides on H2S-poisoned sites. Although H2S was observed to leave the catalyst bed during regeneration, sulfur remained on the catalyst, and a transformation from sulfides to sulfates was observed. Following the oxidative regeneration, the subsequent H2 reduction led to a partial reduction of sulfates back to sulfides, indicating the difficulty and sensitivity in achieving complete sulfur removal during regeneration for biomass-conditioning catalysts.
Yung, M. M.; Cheah, S.; Magrini-Bair, K.; Kuhn, J. N.
Energy and global warming impacts of next generation refrigeration and air conditioning technologies
Significant developments have occurred in hydrofluorocarbon (HFC) and the application of ammonia and hydrocarbons as refrigerant working fluids since the original TEWI (Total Equivalent Warming Impact) report in 1991. System operating and performance data on alternative refrigerants and refrigeration technologies justify and updated evaluation of these new alternative refrigerants and competing technologies in well-characterized applications. Analytical and experimental results are used to show quantitative comparisons between HFCS, HFC blends, hydrocarbons, and ammonia, used as refrigerants. An objective evaluation is presented for commercial and near commercial non-CFC refrigerants/blowing agents and alternative refrigeration technologies. This information is needed for objective and quantitative decisions on policies addressing greenhouse gas emissions from refrigeration and air conditioning equipment. The evaluation assesses the energy use and global warming impacts of refrigeration and air conditioning technologies that could be commercialized during the phase out of HCFCS. Quantitative comparison TEWI for two application areas are presented. Opportunities for significant reductions in TEWI are seen with currently known refrigerants through improved maintenance and servicing practices and improved product designs.
Sand, J.R.; Fischer, S.K.; Baxter, V.D.
The Influence of Air-Conditioning Efficiency in the Peak Load Demand for Kuwait
A model co-relating the peak load demand of a utility with the allowable power rating (PR) of air-conditioning (AC) systems has been developed in this paper through a well defined methodology. The model is capable to predict the extent of allowable increase in the capital cost of the AC system for an improvement in PR from its base case as well. Furthermore, effectiveness of better PR of AC system for peak load management has been analyzed for Kuwait as a case study. It is found that up to 5,752 MW in reduction in peak load demand and savings of KD 2,301 million in capital expenditures are possible for the years between 2001 and 2025 if the PR of AC systems are improved to 1.2 kW/RT from its present level of 2.0 kW/RT. Also, it is estimated that extent of increase in capital cost of AC system by 106 % is justified for reducing the expenditure for new power plants. The paper will be useful for the energy planner and policy makers in the countries of Arabian Peninsula with huge demand for air-conditioning.
Ali, A. A.; Maheshwari, G. P.
A genetic rule weighting and selection process for fuzzy control of heating, ventilating and air conditioning systems
In this paper, we propose the use of weighted linguistic fuzzy rules in combination with a rule selection process to develop accurate fuzzy logic controllers dedicated to the intelligent control of heating, ventilating and air conditioning systems concerning ... Keywords: BEMS, building energy management system, FLC, fuzzy logic controller, Fuzzy logic controllers, GA, genetic algorithm, Genetic algorithms, HVAC systems, HVAC, heating, ventilating, and air conditioning, KB, knowledge base, PMV, predicted mean vote index for thermal comfort, Rule selection, Weighted fuzzy rules
Rafael Alcal�; Jorge Casillas; Oscar Cord�n; Antonio Gonz�lez; Francisco Herrera
Experimental investigation on the photovoltaic-thermal solar heat pump air-conditioning system on water-heating mode
An experimental study on operation performance of photovoltaic-thermal solar heat pump air-conditioning system was conducted in this paper. The experimental system of photovoltaic-thermal solar heat pump air-conditioning system was set up. The performance parameters such as the evaporation pressure, the condensation pressure and the coefficient of performance (COP) of heat pump air-conditioning system, the water temperature and receiving heat capacity in water heater, the photovoltaic (PV) module temperature and the photovoltaic efficiency were investigated. The experimental results show that the mean photovoltaic efficiency of photovoltaic-thermal (PV/T) solar heat pump air-conditioning system reaches 10.4%, and can improve 23.8% in comparison with that of the conventional photovoltaic module, the mean COP of heat pump air-conditioning system may attain 2.88 and the water temperature in water heater can increase to 42 C. These results indicate that the photovoltaic-thermal solar heat pump air-conditioning system has better performances and can stably work. (author)
Fang, Guiyin; Hu, Hainan; Liu, Xu [Department of Physics, Nanjing University, Nanjing 210093 (China)
Energy Consumption Measuring and Diagnostic Analysis of Air-conditioning Water System in a Hotel Building in Harbin
This paper introduces an air-conditioning water system in a hotel building in Harbin, finishes its air-conditioning energy consumption measurement in summer conditions, and presents an estimation index of performance of chiller, pump and motor. By means of testing data analysis, it is indicated that several problems such as unsuitable operation schedule of the chiller, low COP, irrational matching of pump and motor, unbalanced conditions of chilled water flow, and low working stability and efficiency ratio of the pump are existent. The paper presents suggestions for improvement with relevance based on the induction and analysis of system fault found in measurements.
Zhao, T.; Zhang, J.; Li, Y.
Structural analysis of porous rock reservoirs subjected to conditions of compressed air energy storage
Investigations are described which were performed to assess the structural behavior of porous rock compressed air energy storage (CAES) reservoirs subjected to loading conditions of temperature and pressure felt to be typical of such an operation. Analyses performed addressed not only the nominal or mean reservoir response but also the cyclic response due to charge/discharge operation. The analyses were carried out by assuming various geometrical and material related parameters of a generic site. The objective of this study was to determine the gross response of a generic porous reservoir. The site geometry for this study assumed a cylindrical model 122 m in dia and 57 m high including thicknesses for the cap, porous, and base rock formations. The central portion of the porous zone was assumed to be at a depth of 518 m and at an initial temperature of 20/sup 0/C. Cyclic loading conditions of compressed air consisted of pressure values in the range of 4.5 to 5.2 MPa and temperature values between 143 and 204/sup 0/C.Various modes of structural behavior were studied. These response modes were analyzed using loading conditions of temperature and pressure (in the porous zone) corresponding to various operational states during the first year of simulated site operation. The results of the structural analyses performed indicate that the most severely stressed region will likely be in the wellbore vicinity and hence highly dependent on the length of and placement technique utilized in the well production length. Analyses to address this specific areas are currently being pursued.
Friley, J.R.
Computational Assessment of the GT-MHR Graphite Core Support Structural Integrity in Air-Ingress Accident Condition
The objective of this project was to perform stress analysis for graphite support structures of the General Atomics� 600 MWth GT-MHR prismatic core design using ABAQUS � (ver. 6.75) to assess their structural integrity in air-ingress accident conditions where the structure weakens over time due to oxidation damages. The graphite support structures of prismatic type GT-MHR was analyzed based on the change of temperature, burn-off and corrosion depth during the accident period predicted by GAMMA, a multi-dimensional gas multi-component mixture analysis code developed in the Republic of Korea (ROK)/United States (US) International �Nuclear Engineering Research Initiative (I-NERI) project. Both the loading and thermal stresses were analyzed, but the thermal stress was not significant, leaving the loading stress to be the major factor. The mechanical strengths are exceeded between 11 to 11.5 days after loss-of-coolant-accident (LOCA), corresponding to 5.5 to 6 days after the start of natural convection.
Jong B. Lim; Eung S. Kim; Chang H. Oh; Richard R. Schultz; David A. Petti
High Efficiency Liquid-Desiccant Regenerator for Air Conditioning and Industrial Drying
Over 2 quads of fossil fuels are used each year for moisture removal. This includes industrial and agricultural processes where feedstocks and final products must be dried, as well as comfort conditioning of indoor spaces where the control of humidity is essential to maintaining healthy, productive and comfortable working conditions. Desiccants, materials that have a high affinity for water vapor, can greatly reduce energy use for both drying and dehumidification. An opportunity exists to greatly improve the competitiveness of advanced liquid-desiccant systems by increasing the efficiency of their regenerators. It is common practice within the chemical process industry to use multiple stage boilers to improve the efficiency of thermal separation processes. The energy needed to regenerate a liquid desiccant, which is a thermal separation process, can also be reduced by using a multiple stage boiler. In this project, a two-stage regenerator was developed in which the first stage is a boiler and the second stage is a scavenging-air regenerator. The only energy input to this regenerator is the natural gas that fires the boiler. The steam produced in the boiler provides the thermal energy to run the second-stage scavenging-air regenerator. This two-stage regenerator is referred to as a 1?-effect regenerator. A model of the high-temperature stage of a 1?-effect regenerator for liquid desiccants was designed, built and successfully tested. At nominal operating conditions (i.e., 2.35 gpm of 36% lithium chloride solution, 307,000 Btu/h firing rate), the boiler removed 153 lb/h of water from the desiccant at a gas-based efficiency of 52.9 % (which corresponds to a COP of 0.95 when a scavenging-air regenerator is added). The steam leaving the boiler, when condensed, had a solids concentration of less than 10 ppm. This low level of solids in the condensate places an upper bound of about 6 lb per year for desiccant loss from the regenerator. This low loss will not create maintenance problems nor will it significantly increase operating expenses. An energy balance on the boiler showed that heat loss through the insulated jacket was 10%. This value is much higher than the 2% to 5% that is typical of most boilers and indicates a need to better insulate the unit. With insulation that brings jacket losses down to 5%, a 1?-effect regenerator that uses this boiler as its high-temperature stage will have a gas-based COP of 1.05. The estimated cost to manufacture a 300-lb/h, 1?-effect regenerator at 500 units per year is $17,140. Unfortunately, the very high cost for natural gas that now prevails in the U.S. makes it very difficult for a gas-fired LDAC to compete against an electric vapor-compression air conditioner in HVAC applications. However, there are important industrial markets that need very dry air where the high price of natural gas will encourage the sale of a LDAC with the 1?-effect regenerator since in these markets it competes against less efficient gas-fired desiccant technologies. A manufacturer of industrial dehumidification equipment is now negotiating a sales agreement with us that would include the 1?-effect regenerator.
Andrew Lowenstein
Smart Operations of Air-Conditioning and Lighting Systems in Government Buildings for Peak Power Reduction
During the summer 2007 smart operation strategies for air-conditioning (A/C) and lighting systems were developed and tested in a number of governmental buildings in Kuwait as one of the solutions to reduce the national peak demand for electrical power that commonly occur around 15:00 h. The working hours for these building are generally between 07:00 and 14:00 h and their peak demand exceeds 600 MW. The smart operation strategies implemented in these buildings included pre-closing treatment (PCT) between 13:00 and 14:00 h and time-of-day control (TDC) after 14:00 h. Also de-lamping was carried out in some of the buildings to readjust the higher than recommended illumination levels. This paper presents the achievements of implementing these smart operations strategies in Justice Palace Complex (JPC) as a case study. The peak load of this building was 3700 kW. The achievements are summarized as an all time saving of 22 kW by de-lamping, an additional saving of 27 kW through TDC of lighting, direct savings between 13:00 and 22:00 h by closing supply and return air fans of 52 air-handling units with a connected load 400 kW, and an additional saving of 550 kW during the same period by optimizing the cooling production and distribution. In conclusion project achieved an overall reduction in power demand of around 20% between 13:00 to 17:00 h and reduction ranging from 7% to 15% between 17:00 to 20:00 h.
Al-Hadban, Y.; Maheshwari, G. P.; Al-Nakib, D.; Al-Mulla, A.; Alasseri, R.
Evaluation Framework and Analyses for Thermal Energy Storage Integrated with Packaged Air Conditioning
Few third-party guidance documents or tools are available for evaluating thermal energy storage (TES) integrated with packaged air conditioning (AC), as this type of TES is relatively new compared to TES integrated with chillers or hot water systems. To address this gap, researchers at the National Renewable Energy Laboratory conducted a project to improve the ability of potential technology adopters to evaluate TES technologies. Major project outcomes included: development of an evaluation framework to describe key metrics, methodologies, and issues to consider when assessing the performance of TES systems integrated with packaged AC; application of multiple concepts from the evaluation framework to analyze performance data from four demonstration sites; and production of a new simulation capability that enables modeling of TES integrated with packaged AC in EnergyPlus. This report includes the evaluation framework and analysis results from the project.
Kung, F.; Deru, M.; Bonnema, E.
Japanese power electronics inverter technology and its impact on the American air conditioning industry
Since 1983, technological advances and market growth of inverter- driven variable-speed heat pumps in Japan have been dramatic. The high level of market penetration was promoted by a combination of political, economic, and trade policies in Japan. A unique environment was created in which the leading domestic industries-- microprocessor manufacturing, compressors for air conditioning and refrigerators, and power electronic devices--were able to direct the development and market success of inverter-driven heat pumps. As a result, leading US variable-speed heat pump manufacturers should expect a challenge from the Japanese producers of power devices and microprocessors. Because of the vertically-integrated production structure in Japan, in contrast to the out-sourcing culture of the United States, price competition at the component level (such as inverters, sensors, and controls) may impact the structure of the industry more severely than final product sales. 54 refs., 47 figs., 1 tab.
Ushimaru, Kenji.
Effect of Intake Air Filter Condition on Vehicle Fuel Economy--ORNL/TM-2009/021
021 021 Effect of Intake Air Filter Condition on Vehicle Fuel Economy February 2009 Prepared by Kevin Norman Shean Huff Brian West DOCUMENT AVAILABILITY Reports produced after January 1, 1996, are generally available free via the U.S. Department of Energy (DOE) Information Bridge. Web site http://www.osti.gov/bridge Reports produced before January 1, 1996, may be purchased by members of the public from the following source. National Technical Information Service 5285 Port Royal Road Springfield, VA 22161 Telephone 703-605-6000 (1-800-553-6847) TDD 703-487-4639 Fax 703-605-6900 E-mail email@example.com Web site http://www.ntis.gov/support/ordernowabout.htm Reports are available to DOE employees, DOE contractors, Energy Technology Data Exchange
The influence of bowl offset on air motion in a direct injection diesel engine
The influence of bowl offset on motored mean flow and turbulence in a direct injection diesel engine has been examined with the aid of a multi-dimensional flow code. Results are presented for three piston geometries. The bowl geometry of each piston was the same, while the offset between the bowl and the cylinder axis was varied from 0.0 to 9.6% of the bore. The swirl ratio at intake valve closing was also varied from 2.60 to 4.27. It was found that the angular momentum of the air at TDC was decreased by less than 8% when the bowl was offset. Nevertheless, the mean (squish and swirl) flows were strongly affected by the offset. In addition, the distribution of turbulent kinetic energy (predicted by the /delta/-e model) was modified. Moderate increases (10% or less) in mass averaged turbulence intensity at TDC with offset were observed.
McKinley, T.L.; Primus, R.J
LA-UR-11-05888 Page 1 Opening Session: Engineering and Materials at Extreme Conditions
National Nuclear Security Administration (NNSA)
88 88 Page 1 Opening Session: Engineering and Materials at Extreme Conditions Simulation for Predictive Science: The Promises and the Challenges of Exascale Computing Cheryl L. Wampler* and Andrew B. White† Los Alamos National Laboratory Los Alamos, NM 87545 USA Summary: Large-scale simulation is a key tool, together with experimentation, used to gain understanding of and model materials and their behavior under extreme physical conditions, and to incorporate that understanding into a broader framework that allows one to explore and predict how complex, engineered systems behave, particularly under conditions which cannot be directly tested through experiments. These are difficult tasks, and it is anticipated that exascale (10 18 FLOPs, or floating point arithmetic operations per second) computing will be needed to solve
NREL's Energy-Saving Technology for Air Conditioning Cuts Peak Power Loads Without Using Harmful Refrigerants (Fact Sheet)
This fact sheet describes how the DEVAP air conditioner was invented, explains how the technology works, and why it won an R&D 100 Award. Desiccant-enhanced evaporative (DEVAP) air-conditioning will provide superior comfort for commercial buildings in any climate at a small fraction of the electricity costs of conventional air-conditioning equipment, releasing far less carbon dioxide and cutting costly peak electrical demand by an estimated 80%. Air conditioning currently consumes about 15% of the electricity generated in the United States and is a major contributor to peak electrical demand on hot summer days, which can lead to escalating power costs, brownouts, and rolling blackouts. DEVAP employs an innovative combination of air-cooling technologies to reduce energy use by up to 81%. DEVAP also shifts most of the energy needs to thermal energy sources, reducing annual electricity use by up to 90%. In doing so, DEVAP is estimated to cut peak electrical demand by nearly 80% in all climates. Widespread use of this cooling cycle would dramatically cut peak electrical loads throughout the country, saving billions of dollars in investments and operating costs for our nation's electrical utilities. Water is already used as a refrigerant in evaporative coolers, a common and widely used energy-saving technology for arid regions. The technology cools incoming hot, dry air by evaporating water into it. The energy absorbed by the water as it evaporates, known as the latent heat of vaporization, cools the air while humidifying it. However, evaporative coolers only function when the air is dry, and they deliver humid air that can lower the comfort level for building occupants. And even many dry climates like Phoenix, Arizona, have a humid season when evaporative cooling won't work well. DEVAP extends the applicability of evaporative cooling by first using a liquid desiccant-a water-absorbing material-to dry the air. The dry air is then passed to an indirect evaporative cooling stage, in which the incoming air is in thermal contact with a moistened surface that evaporates the water into a separate air stream. As the evaporation cools the moistened surface, it draws heat from the incoming air without adding humidity to it. A number of cooling cycles have been developed that employ indirect evaporative cooling, but DEVAP achieves a superior efficiency relative to its technological siblings.
Energy Comparison Between Conventional and Chilled Water Thermal Storage Air Conditioning Systems
During the summer of previous years, Kuwait faced a series of power shortages emphasizing the need for urgent commissioning of power generation projects. It is estimated that the demand for electricity is growing at an average of 6.2% per year, encouraged by government subsidies and driven by the rapid and continual expansion in building construction, urban development, and the heavy reliance on Air Conditioning (AC) systems for the cooling of buildings. The Chilled Water Thermal Storage (CWTS) system is one of the available techniques that can be utilized to reduce peak electricity demand of buildings when national electricity consumption is at its highest level. This paper demonstrates that the use of CWTS system reduces the peak power demand and energy consumption of AC systems for design day conditions by 36.7% - 87.5% and 5.4% - 7.2%, respectively. This reduction depends on selected operating strategies as compared with conventional AC system. Furthermore, results show that the annual energy consumption of CWTS systems decreases by between 4.5% and 6.9% compared with conventional systems, where chillers and pumps significantly contribute to this reduction.
Sebzali, M.; Hussain, H. J.; Ameer, B.
Regression analysis of residential air-conditioning energy consumption at Dhahran, Saudi Arabia
The energy consumption of a house air conditioner located at Dhahran, Saudi Arabia, is modeled as a function of weather parameters and total (global) solar radiation on a horizontal surface. The selection of effective parameters that significantly influence energy consumption is carried out using general stepping regression methods. The problem of collinearity between the regressors is also investigated. The final model involves parameters of total solar radiation on a horizontal surface, wind speed, and temperature difference between the indoor and outdoor condition. However, the model coefficients are functions of relative humidity and/or temperature difference between the indoor and outdoor condition. Model adequacy is examined by the residual analysis technique. Model validation is carried out by the data-splitting technique. The sensitivity of the model indicates that relative humidity and temperature difference strongly influence the cooling energy consumption. It was found that an increase in relative humidity from 20% to 100% can cause a 100% increase in cooling energy consumption during the high cooling season.
Abdel-Nabi, D.Y.; Zubair, S.M.; Abdelrahman, M.A.; Bahel, V. (Energy Systems Group, Div. of Energy Resources, Research Inst., King Fahd Univ. of Petroleum and Minerals, Dhahran (SA))
Modelica Library for Building Heating, Ventilation and Air-Conditioning Systems
This paper presents a freely available Modelica library for building heating, ventilation and air conditioning systems. The library is based on the Modelica.Fluid library. It has been developed to support research and development of integrated building energy and control systems. The primary applications are controls design, energy analysis and model-based operation. The library contains dynamic and steady-state component models that are applicable for analyzing fast transients when designing control algorithms and for conducting annual simulations when assessing energy performance. For most models, dimensional analysis is used to compute the performance for operating points that differ from nominal conditions. This allows parameterizing models in the absence of detailed geometrical information which is often impractical to obtain during the conceptual design phase of building systems. In the first part of this paper, the library architecture and the main classes are described. In the second part, an example is presented in which we implemented a model of a hydronic heating system with thermostatic radiator valves and thermal energy storage.
Wetter, Michael
Numerical Simulations of the Meteorological and Dispersion Conditions during an Air Pollution Episode over Athens, Greece
In this study a summer air pollution episode from 6 to 8 August 1994 over Athens, Greece, is investigated through advanced atmospheric modeling. This episode was reported from the air quality monitoring network, as well as from research aircraft ...
V. Kotroni; G. Kallos; K. Lagouvardos; M. Varinou; R. Walko
Fuel Savings and Emission Reductions from Next-Generation Mobile Air Conditioning Technology in India
Up to 19.4% of vehicle fuel consumption in India is devoted to air conditioning (A/C). Indian A/C fuel consumption is almost four times the fuel penalty in the United States and close to six times that in the European Union because India's temperature and humidity are higher and because road congestion forces vehicles to operate inefficiently. Car A/C efficiency in India is an issue worthy of national attention considering the rate of increase of A/C penetration into the new car market, India's hot climatic conditions and high fuel costs. Car A/C systems originally posed an ozone layer depletion concern. Now that industrialized and many developing countries have moved away from ozone-depleting substances per Montreal Protocol obligations, car A/C impact on climate has captured the attention of policy makers and corporate leaders. Car A/C systems have a climate impact from potent global warming potential gas emissions and from fuel used to power the car A/Cs. This paper focuses on car A/C fuel consumption in the context of the rapidly expanding Indian car market and how new technological improvements can result in significant fuel savings and consequently, emission reductions. A 19.4% fuel penalty is associated with A/C use in the typical Indian passenger car. Car A/C fuel use and associated tailpipe emissions are strong functions of vehicle design, vehicle use, and climate conditions. Several techniques: reducing thermal load, improving vehicle design, improving occupants thermal comfort design, improving equipment, educating consumers on impacts of driver behaviour on MAC fuel use, and others - can lead to reduced A/C fuel consumption.
Chaney, L.; Thundiyil, K.; Andersen, S.; Chidambaram, S.; Abbi, Y. P.
Global warming impacts of ozone-safe refrigerants and refrigeration, heating, and air-conditioning technologies
International agreements mandate the phase-out of many chlorine containing compounds that are used as the working fluid in refrigeration, air-conditioning, and heating equipment. Many of the chemical compounds that have been proposed, and are being used in place of the class of refrigerants eliminated by the Montreal Protocol are now being questioned because of their possible contributions to global warming. Natural refrigerants are put forth as inherently superior to manufactured refrigerants because they have very low or zero global warming potentials (GWPs). Questions are being raised about whether or not these manufactured refrigerants, primarily hydrofluorocarbons (HFCs), should be regulated and perhaps phased out in much the same manner as CFCs and HCFCs. Several of the major applications of refrigerants are examined in this paper and the results of an analysis of their contributions to greenhouse warming are presented. Supermarket refrigeration is shown to be an application where alternative technologies have the potential to reduce emissions of greenhouse gases (GHG) significantly with no clear advantage to either natural or HFC refrigerants. Mixed results are presented for automobile air conditioners with opportunities to reduce GHG emissions dependent on climate and comfort criteria. GHG emissions for hermetic and factory built systems (i.e. household refrigerators/freezers, unitary equipment, chillers) are shown to be dominated by energy use with much greater potential for reduction through efficiency improvements than by selection of refrigerant. The results for refrigerators also illustrate that hydrocarbon and carbon dioxide blown foam insulation have lower overall effects on GHG emissions than HFC blown foams at the cost of increased energy use.
Fischer, S.; Sand, J.; Baxter, V.
"Table HC3.6 Air Conditioning Characteristics by Owner-Occupied Housing Units, 2005"
6 Air Conditioning Characteristics by Owner-Occupied Housing Units, 2005" 6 Air Conditioning Characteristics by Owner-Occupied Housing Units, 2005" " Million U.S. Housing Units" ,," Owner-Occupied Housing Units (millions)","Type of Owner-Occupied Housing Unit" ,"U.S. Housing Units (millions" ,,,"Single-Family Units",,"Apartments in Buildings With--" "Air Conditioning Characteristics",,,"Detached","Attached","2 to 4 Units","5 or More Units","Mobile Homes" "Total",111.1,78.1,64.1,4.2,1.8,2.3,5.7 "Do Not Have Cooling Equipment",17.8,11.3,9.3,0.6,"Q",0.4,0.9 "Have Cooling Equipment",93.3,66.8,54.7,3.6,1.7,1.9,4.8 "Use Cooling Equipment",91.4,65.8,54,3.6,1.7,1.9,4.7
Upgrading of the Air-conditioning of the Computer Room in the Computer Centre for the LHC era
Built in the beginning of 1970's, the Computer Centre air-conditioning and cooling systems were designed to be modular and easily adaptable to the unpredictable future needs of computing. The infrastructure of LHC-computing that will be housed in the existing Computer Room with its five Computing farms and over 11000 PC's increases the requirements of cooling and air-conditioning power to a new level. The nominal thermal loads from the equipment rise from the current design maximum of 1MW to estimated maximum of 2MW in the future. This paper presents calculations and proposes solutions to meet the new nominal requirements. The air-conditioning system must also be able to cope with a situation of power cut in the main supply. A calculation of the temperature evolution during the power cut and a justified operation strategy for this scenario is also presented.
"Table HC3.7 Air-Conditioning Usage Indicators by Owner-Occupied Housing Unit, 2005"
7 Air-Conditioning Usage Indicators by Owner-Occupied Housing Unit, 2005" 7 Air-Conditioning Usage Indicators by Owner-Occupied Housing Unit, 2005" " Million U.S. Housing Units" ,," Owner-Occupied Housing Units (millions)","Type of Owner-Occupied Housing Unit" ,"U.S. Housing Units (millions)" ,,,"Single-Family Units",,"Apartments in Buildings With--" "Air Conditioning Usage Indicators",,,"Detached","Attached","2 to 4 Units","5 or More Units","Mobile Homes" "Total",111.1,78.1,64.1,4.2,1.8,2.3,5.7 "Do Not Have Cooling Equipment",17.8,11.3,9.3,0.6,"Q",0.4,0.9 "Have Cooling Equipment",93.3,66.8,54.7,3.6,1.7,1.9,4.8 "Use Cooling Equipment",91.4,65.8,54,3.6,1.7,1.9,4.7
Two-dimensional model of the air flow and temperature distribution in a cavity-type heat receiver of a solar stirling engine
A theoretical study on the air flow and temperature in the heat receiver, affected by free convection, of a Stirling Engine for a Dish/Stirling Engine Power System is presented. The standard {kappa}-{epsilon} turbulence model for the fluid flow has been used and the boundary conditions employed were obtained using a second level mathematical model of the Stirling Engine working cycle. Physical models for the distribution of the solar insolation from the Concentrator on the bottom and side walls of the cavity-type heat receiver have been taken into account. The numerical results show that most of the heat losses in the receiver are due to re-radiation from the cavity and conduction through the walls of the cavity. It is in the region of the boundary of the input window of the heat receiver where there is a sensible reduction in the temperature in the shell of the heat exchangers and this is due to the free convection of the air. Further, the numerical results show that convective heat losses increase with decreasing tilt angle.
Makhkamov, K.K.; Ingham, D.B.
Energy Savings and Economics of Advanced Control Strategies for Packaged Air-Conditioning Units with Gas Heat
Pacific Northwest National Laboratory (PNNL) with funding from the U.S. Department of Energy's Building Technologies Program (BTP) evaluated a number of control strategies that can be implemented in a controller, to improve the operational efficiency of the packaged air conditioning units. The two primary objectives of this research project are: (1) determine the magnitude of energy savings achievable by retrofitting existing packaged air conditioning units with advanced control strategies not ordinarily used for packaged units and (2) estimating what the installed cost of a replacement control with the desired features should be in various regions of the U.S. This document reports results of the study.
Wang, Weimin; Katipamula, Srinivas; Huang, Yunzhi; Brambley, Michael R.
The Coordinated Control of a Central Air Conditioning System Based on Variable Chilled Water Temperature and Variable Chilled Water Flow
At present, regulation of water flow by means of pump frequency conversion is one of the major methods for power-saving in central air conditioning systems. In this article, optimization regulation for central air conditioning system on the basis of coordinative optimization control for variable chilled water temperature and variable chilled water flow to obtain better power savings is put forward. According to typical meteorological year data, hourly air conditioning load of whole year for every typical room has been calculated with the transmission function method. In order to guarantee each typical room, the highest cooling load rate is used as an input parameter for optimization calculation. Based on the surface cooler check model, the smallest energy consumption of chiller and chiller water pump was taken as the objective function of the optimization model. The performance characteristics of a chiller, water pump, regulation valve and pipeline are taken into account, and the optimization chilled water temperature and chilled water flow were carried out. The case study for a commercial building in Guangzhou showed that the annual power consumption of the chillers and pumps of the air conditioning system is lower by 17% only with employment of variable water flow regulation by pump frequency conversion. In the case of optimization control with coordinative control of variable chilled water temperature and variable chilled water flow, the annual power consumption of the chillers and pumps of the air conditioning system is reduced by 22% in presence of remarkable power saving effects. Increasing the chilled water temperature will reduce the dehumidified capability of the air cooler, and the indoor relative humidity will increase. The simulation showed that the adjustment optimized process meets the comfort of each typical room. The lower the cooling load rate is, the more obvious the effect of power-saving is. The highest power-saving rate appears in December, which is 36.7%. Meanwhile, the least rate appears in July, which is only 14.5%.
Liu, J.; Mai, Y.; Liu, X.
Conceptual design and engineering studies of adiabatic compressed air energy storage (CAES) with thermal energy storage
The objective of this study was to perform a conceptual engineering design and evaluation study and to develop a design for an adiabatic CAES system using water-compensated hard rock caverns for compressed air storage. The conceptual plant design was to feature underground containment for thermal energy storage and water-compensated hard rock caverns for high pressure air storage. Other design constraints included the selection of turbomachinery designs that would require little development and would therefore be available for near-term plant construction and demonstration. The design was to be based upon the DOE/EPRI/PEPCO-funded 231 MW/unit conventional CAES plant design prepared for a site in Maryland. This report summarizes the project, its findings, and the recommendations of the study team; presents the development and optimization of the plant heat cycle and the selection and thermal design of the thermal energy storage system; discusses the selection of turbomachinery and estimated plant performance and operational capability; describes the control system concept; and presents the conceptual design of the adiabatic CAES plant, the cost estimates and economic evaluation, and an assessment of technical and economic feasibility. Particular areas in the plant design requiring further development or investigation are discussed. It is concluded that the adiabatic concept appears to be the most attractive candidate for utility application in the near future. It is operationally viable, economically attractive compared with competing concerns, and will require relatively little development before the construction of a plant can be undertaken. It is estimated that a utility could start the design of a demonstration plant in 2 to 3 years if research regarding TES system design is undertaken in a timely manner. (LCL)
Hobson, M. J.
Air-Source Heat Pumps for Residential and Light Commercial Space Conditioning Applications
This technology brief provides the latest information on current and emerging air-source heat pump technologies for space heating and space cooling of residential and light commercial buildings. Air-source heat pumps provide important options that can reduce ownership costs while reducing noise and enhancing reliability and customer comfort. The tech brief also describes new air-source heat pumps with an important load shaping and demand response option.
Effect of nozzle orifice geometry on spray, combustion, and emission characteristics under diesel engine conditions.
Diesel engine performance and emissions are strongly coupled with fuel atomization and spray processes, which in turn are strongly influenced by injector flow dynamics. Modern engines employ micro-orifices with different orifice designs. It is critical to characterize the effects of various designs on engine performance and emissions. In this study, a recently developed primary breakup model (KH-ACT), which accounts for the effects of cavitation and turbulence generated inside the injector nozzle is incorporated into a CFD software CONVERGE for comprehensive engine simulations. The effects of orifice geometry on inner nozzle flow, spray, and combustion processes are examined by coupling the injector flow and spray simulations. Results indicate that conicity and hydrogrinding reduce cavitation and turbulence inside the nozzle orifice, which slows down primary breakup, increasing spray penetration, and reducing dispersion. Consequently, with conical and hydroground nozzles, the vaporization rate and fuel air mixing are reduced, and ignition occurs further downstream. The flame lift-off lengths are the highest and lowest for the hydroground and conical nozzles, respectively. This can be related to the rate of fuel injection, which is higher for the hydroground nozzle, leading to richer mixtures and lower flame base speeds. A modified flame index is employed to resolve the flame structure, which indicates a dual combustion mode. For the conical nozzle, the relative role of rich premixed combustion is enhanced and that of diffusion combustion reduced compared to the other two nozzles. In contrast, for the hydroground nozzle, the role of rich premixed combustion is reduced and that of non-premixed combustion is enhanced. Consequently, the amount of soot produced is the highest for the conical nozzle, while the amount of NOx produced is the highest for the hydroground nozzle, indicating the classical tradeoff between them.
Som, S.; Longman, D. E; Ramirez, A. I.; Aggarwal, S. K. (Energy Systems); (Univ. of Illinois at Chicago)
The determinants of the governance of air conditioning maintenance in Australian retail centres.
??Retail centres are a visible sign of developed capitalist societies and make an appreciable contribution to these economies. For the firms involved in supplying air� (more)
Bridge, Adrian J.
Performance assessment and improvement of an existing air conditioning system of a supermarket: a case study on bi-lo supermarket
Bi-Lo Supermarket in this study is located in sub-tropical coastal area in Queensland, Australia. The main objective of air conditioning in any building or supermarket is to provide comfort to the occupants and patrons of the conditioned space, an objective ... Keywords: air conditioning systems, design principles, performance improvement, supermarket
M. Hansen; M. G. Rasul
Predictive clothing insulation model based on outdoor air and indoor operative temperatures
ASHRAE. (2010) ANSI/ASHRAE 55-2010: Thermal environmentaland Air-Conditioning Engineers, Atlanta. ASHRAE. (1981) ANSI/ASHRAE Standard 55-1981: Thermal environmental
Schiavon, Stefano; Lee, Kwang Ho
Survey on Electricity Consumption Characteristics of Homethe stakes for energy consumption are high, as we hope atAir Conditioning Energy Consumption in Developing Countries
Using Hydrated Salt Phase Change Materials for Residential Air Conditioning Peak Demand Reduction and Energy Conservation in Coastal and Transitional Climates in the State of California.
??The recent rapid economic and population growth in the State of California have led to a significant increase in air conditioning use, especially in areas� (more)
Lee, Kyoung Ok
Proposal for the award of a contract for the design, supply, installation and commissioning of Heating, Ventilation and Air-Conditioning (HVAC) systems for the PS accelerator infrastructure
Proposal for the award of a contract for dismantling, removal and packaging of the existing Heating, Ventilation and Air-Conditioning (HVAC) systems in the PS tunnel
Engineering Design Example CompressedCompressed--Air System for a Manufacturing PlantAir System for a Manufacturing Plant
to operate C/A tools: Compressor and piping layoutCompressor and piping layout Air supply circumferentially: · Estimate the load [cfm] based on current and future demand. · Size the compressor(s). · Size the pipes so*1.35=1900 cfm. · Centrifugal or reciprocating compressor may be chosen (later). From handbooks: P kk /)1
Kostic, Milivoje M.
This document provides results and conclusions for Task 15.0--Detailed Analysis of Air Balance & Conceptual Design of Improved Air Manifolds in the ''Technologies to Enhance the Operation of Existing Natural Gas Compression Infrastructure'' project. SwRI{reg_sign} is conducting this project for DOE in conjunction with Pipeline Research Council International, Gas Machinery Research Council, El Paso Pipeline, Cooper Compression, and Southern Star, under DOE contract number DE-FC26-02NT41646. The objective of Task 15.0 was to investigate the perceived imbalance in airflow between power cylinders in two-stroke integral compressor engines and develop solutions via manifold redesign. The overall project objective is to develop and substantiate methods for operating integral engine/compressors in gas pipeline service, which reduce fuel consumption, increase capacity, and enhance mechanical integrity.
Gary D. Bourn; Ford A. Phillips; Ralph E. Harris
Gas turbine engine adapted for use in combination with an apparatus for separating a portion of oxygen from compressed air
A gas turbine engine is provided comprising an outer shell, a compressor assembly, at least one combustor assembly, a turbine assembly and duct structure. The outer shell includes a compressor section, a combustor section, an intermediate section and a turbine section. The intermediate section includes at least one first opening and at least one second opening. The compressor assembly is located in the compressor section to define with the compressor section a compressor apparatus to compress air. The at least one combustor assembly is coupled to the combustor section to define with the combustor section a combustor apparatus. The turbine assembly is located in the turbine section to define with the turbine section a turbine apparatus. The duct structure is coupled to the intermediate section to receive at least a portion of the compressed air from the compressor apparatus through the at least one first opening in the intermediate section, pass the compressed air to an apparatus for separating a portion of oxygen from the compressed air to produced vitiated compressed air and return the vitiated compressed air to the intermediate section via the at least one second opening in the intermediate section.
Bland, Robert J. (Oviedo, FL); Horazak, Dennis A. (Orlando, FL)
Study of Air Ingress Across the Duct During the Accident Conditions
The goal of this project is to study the fundamental physical phenoena associated with air ingress in very high temperature reactors (VHTRs). Air ingress may occur due to a nupture of primary piping and a subsequent breach in the primary pressure boundary in helium-cooled and graphite-moderated VHTRs. Significant air ingress is a concern because it introduces potential to expose the fuel, graphite support rods, and core to a risk of severe graphite oxidation. Two of the most probable air ingress scenarios involve rupture of a control rod or fuel access standpipe, and rupture in the main coolant pipe on the lower part of the reactor pressure vessel. Therefor, establishing a fundamental understanding of air ingress phenomena is critical in order to rationally evaluate safety of existing VHTRs and develop new designs that mimimize these risks. But despite this importance, progress toward development these predictive capabilities has been slowed by the complex nature of the underlaying phenomena. The combination of interdiffusion among multiple species, molecular diffusion, natural convection, and complex geometries, as well as the multiple chemical reactions involved, impose significant roadblocks to both modeling and experiment design. The project team will employ a coordinated experimental and computational effort that will help gain a deeper understanding of multiphased air ingress phenomena. THis project will enhance advanced modeling and simulation methods, enabling calculation of nuclear power plant transients and accident scenarios with a high degree of confidence. The following are the project tasks: Perform particle image velocimetry measurement of multiphase air ingresses Perform computational fluid dynamics analysis of air ingress phenomena
Hassan, Yassin
Experimental Research and Performance Analysis of a Solar-Powered Air-conditioning System in a Green Building
Based on the green building of the Shanghai Institute of Architectural Science, a solar-powered adsorption air-conditioning system was designed. The operational performance under a typical operating mode in summer was studied, which includes temperature variations of solar collector arrays, heat storage tank and adsorption chillers as well as refrigerating output variations of the system. Experimental results show that adsorption chillers have the advantages of low driving temperature, stability and long working time with high efficiency. Under representative working conditions in summer, the average refrigerating output of solar powered air-conditioning system is 15.31kW during operation of 8 hours; moreover, the maximum attains 20kW. Correspondingly, the average system COP is 0.35, and the average solar COP is 0.15. The solar fraction in summer is concluded to be 71.73%. In addition, the variations of solar-powered air-conditioning system performance with ambient parameters (solar radiant intensity and ambient temperature) and operating parameters (temperatures and flow rates) are analyzed.
Zhai, X.; Wang, R.; Dai, Y.; Wu, J.
Experimental study of the performance of a laminar flow silica gel desiccant packing suitable for solar air conditioning application
An experimental study of the performance of a low pressure drop silica gel desiccant packing has been carried out. The packing is in the form of narrow passages lined with a single layer of small silica gel particles. A near optimum particle size of 0.25 mm, and a range of passage widths of 1.46 to 3.75 mm were chosen based on the predictions of a computer simulation model. A test chamber was constructed with sufficient thermal insulation to allow close to adiabatic conditions for the 12 cm x 12 cm cross section of packing. Step change adsorption and desorption tests were performed for various plate spacings, air flow rates, air inlet conditions, and gel initial water contents. Air outlet moisture content and temperature, as well as pressure drop were measured. The experimental results were compared with predictions of the computer simulation model: This model is based on gas side controlled heat and mass transfer, with the small solid side mass transfer resistance incorporated in a crude manner, and heat transfer into the packing handled as a lumped thermal capacitance. Reasonable agreement was obtained between theoretical prediction and experiment. The match was found to improve with increased passage width. The discrepancies are chiefly attributed to an excessive air bypass, and to inaccurate accounting for heat transfer from the sides of the unit. Use of the computer code for prototype scale design purposes is recommended.
Biswas, P.
Next Generation Natural Gas Vehicle Program Phase I: Clean Air Partners 0.5 g/hp-h NOx Engine Concept; Final Report
Subcontractor report details work done by Clean Air Partners to develop 0.5 g/hp-h NOx natural gas engine exhaust gas recirculation (EGR) technology for the Next Generation Natural Gas Vehicle Program.
Wong, H. C.
A multi-objective evolutionary algorithm for an effective tuning of fuzzy logic controllers in heating, ventilating and air conditioning systems
This paper focuses on the use of multi-objective evolutionary algorithms to develop smartly tuned fuzzy logic controllers dedicated to the control of heating, ventilating and air conditioning systems, energy performance, stability and indoor comfort ... Keywords: Fuzzy logic controllers, Genetic tuning, HVAC systems, Heating, ventilating, and air conditioning systems, Linguistic 2-tuples representation, Multi-objective evolutionary algorithms, Rule selection
Mar�a Jos� Gacto; Rafael Alcal�; Francisco Herrera
Exhaust gas recirculation in a homogeneous charge compression ignition engine
A homogeneous charge compression ignition engine operates by injecting liquid fuel directly in a combustion chamber, and mixing the fuel with recirculated exhaust and fresh air through an auto ignition condition of the fuel. The engine includes at least one turbocharger for extracting energy from the engine exhaust and using that energy to boost intake pressure of recirculated exhaust gas and fresh air. Elevated proportions of exhaust gas recirculated to the engine are attained by throttling the fresh air inlet supply. These elevated exhaust gas recirculation rates allow the HCCI engine to be operated at higher speeds and loads rendering the HCCI engine a more viable alternative to a conventional diesel engine.
Duffy, Kevin P. (Metamora, IL); Kieser, Andrew J. (Morton, IL); Rodman, Anthony (Chillicothe, IL); Liechty, Michael P. (Chillicothe, IL); Hergart, Carl-Anders (Peoria, IL); Hardy, William L. (Peoria, IL)
Energy audits reveal significant energy savings potential in India`s commercial air-conditioned building sector
The United States Agency for International Development (USAID) began its Energy Management Consultation and Training (EMCAT) project in India. The EMCAT project began in 1991 as a six-year (1991--1997) project to improve India`s technological and management capabilities for both the supply of energy and its efficient end use. The end-use component of EMCAT aims for efficient energy utilization by industries and other sectors such as the commercial sector. A specific task under the end-use component was to conduct energy surveys/audits in high energy-use sectors, such as air-conditioned (AC) buildings in the commercial sector, and to identify investment opportunities that could improve energy utilization. This article presents results of pre-investment surveys that were conducted at four commercial air-conditioned facilities in 1995. The four facilities included two luxury hotels in New Delhi, and one luxury hotel and a private hospital in Bombay. Energy conservation opportunities (ECOs) were explored in three major energy-using systems in these buildings: air-conditioning, lighting, and steam and domestic hot water systems.
Singh, G.; Presny, D.; Fafard, C. [Resource Management Associates of Madison, Inc., WI (United States)
Dehumidification Performance of Unitary Rooftop Air Conditioning Systems: K-Mart Demonstration
Applying various HVAC options--including heat pipe heat exchangers, reduced airflow, low temperature air, and modified fan operation--reduced the average relative humidity of a K-Mart store on the Mississippi coast during the hot humid summer season to below 50 percent. This demonstration will help utilities recommend the best practices for their retail customers.
A smart GUI based air-conditioning and lighting controller for energy saving in building
This paper will concentrate on the algorithm and control strategies where the air-conditioners and lighting system can be controlled using microcontroller; a microcontroller is chosen due to its low cost and high flexibility. Conceptually, the controller ... Keywords: energy saving control system, graphic LCD, graphical user interface (GUI), microcontroller
M. F. Abas; N. MD. Saad; N. L. Ramli
A thermal comfort levels investigation of a naturally ventilated and air-conditioned office
The purpose of this study is to investigate thermal comfort levels of a naturally ventilated and air-conditioner office. Field experiments conducted in an office room in Universiti Putra Malaysia (UPM) used survey questionnaires and physical measurements. ... Keywords: PMV, mechanically ventilation, naturally ventilated, neutral temperature, objective study, subjective approach, thermal comfort
R. Daghigh; N. M. Adam; K. Sopian; A. Zaharim; B. B. Sahari
A Bulk Turbulent Air�Sea Flux Algorithm for High-Wind, Spray Conditions
Sensible and latent heat can cross the air�sea interface by two routes: as interfacial fluxes controlled by molecular processes right at the interface, and as spray fluxes from the surface of sea spray droplets. Once the 10-m wind speed over the ...
Edgar L. Andreas; P. Ola G. Persson; Jeffrey E. Hare
BIBLIOGRAPHY ON INTERNAL COMBUSTION ENGINES 1. F. Obert, Internal Combustion Engines and Air Pollution, Intext Educational Publishers, 1973
depend on vari- ous factors: engine temperature and load, aftertreatment de- vices and dilution-11545-2010 © Author(s) 2010. CC Attribution 3.0 License. Atmospheric Chemistry and Physics Impact of aftertreatment aftertreatment systems. One vehicle lacked exhaust aftertreatment devices, one ve- hicle was equipped
Entekhabi, Dara
MAGNESIUM OXIDE AN ENGINEERED BARRIER 2009 EPA WIPP RECERTIFICATION FACT SHEET United States Environmental Protection Agency | Office of Air and Radiation (6608J) | June 2009
MAGNESIUM OXIDE AN ENGINEERED BARRIER 2009 EPA WIPP RECERTIFICATION FACT SHEET United States Environmental Protection Agency | Office of Air and Radiation (6608J) | June 2009 http://www.epa.gov/radiation/wipp/index.html MAGNESIUM OXIDE AN ENGINEERED BARRIER Why is MgO Used At WIPP? The U.S. Department of Energy (DOE
Derivation of a merging condition for two interacting streamers in air
The simulation of the interaction of two simultaneously propagating air streamers of the same polarity is presented. A parametric study has been carried out using an accurate numerical method which ensures a time-space error control of the solution. For initial separation of both streamers smaller or comparable to the longest characteristic absorption length of photoionization in air, we have found that the streamers tend to merge at the moment when the ratio between their characteristic width and their mutual distance reaches a value of about 0.35 for positive streamers, and 0.4 for negative ones. Moreover it is demonstrated that these ratios are practically independent of the applied electric field, the initial seed configuration, and the pressure.
Bonaventura, Zdenek; Bourdon, Anne; Massot, Marc
Investigation and Analysis of Energy Consumption and Cost of Electric Air Conditioning Systems in Civil Buildings in Changsha
We investigated 40 typical air conditioned buildings in Changsha in 2005, including 15 hotel buildings, 6 commercial buildings, 5 office buildings, 6 hospital buildings and 8 synthesis buildings. On this basis we analyze the relation between types of cold and heat sources and the HVAC area of the buildings. Meanwhile the economical and feasible types of cold and heat sources are pointed out, i.e., oil boilers and gas boilers for heat source, and centrifugal and screw water chillers for cold source based on the electric refrigeration. Among the heat sources, the prospect of gas boilers is better. In addition, the air source heat pump depends heavily on whether some crucial issues such as frost can be solved during its application. The water-source heat pump will likely be applied. Based on the analysis of energy consumption and energy bills, we determine the feasible measures for energy conservation including the aspects of design, operation and management. Among them, special attention should be paid to energy metering and running time of air conditioning systems in civil buildings in Changsha.
Xie, D.; Chen, J.; Zhang, G.; Zhang, Q.
Risk Factors in Heating, Ventilating, and Air-Conditioning Systems for Occupant Symptoms in
six buildings had cooling towers, of which 46 were cleanedor poor condition of cooling tower was associated with aunscheduled cleaning of cooling towers was associated with
Mendell, M.J.; Lei-Gomez, Q.; Mirer, A.; Seppanen, O.; Brunner, G.
Memorandum To: GENERAL COUNSEL, DEPARTMENT OF ENERGY (DOE) From: JONATHAN MELCHI, HEATING, AIR-CONDITIONING AND REFRIGERATION
To: GENERAL COUNSEL, DEPARTMENT OF ENERGY (DOE) To: GENERAL COUNSEL, DEPARTMENT OF ENERGY (DOE) From: JONATHAN MELCHI, HEATING, AIR-CONDITIONING AND REFRIGERATION DISTRIBUTORS INTERNATIONAL (HARDI) Date: 1/12/2012 Subject: EX PARTE COMMUNICATION MEMO DOE ATTENDEES: Ashley Armstrong, John Cymbalsky, David Case, Laura Barhydt HARDI ATTENDEES: Talbot Gee, Jonathan Melchi AREAS OF DISCUSSION: DOE Framework Document and Stakeholder Meeting regarding the Enforcement of the updated Energy Conservation Standards for Air Conditioners, Furnaces and Heat Pumps. The meeting took place on Thursday January 5 th , 2012 from 2pm to 3-pm. The following topics were discussed. 1.) Sell-Through. HARDI asked for clarification on the DOE's notation on the Framework Document
An analysis of retention issues of scientists, engineers, and program managers in the US Air Force
The United States Air Force is having a difficult time retaining their technical officers, who are critical to the success of their research, development, and acquisitions of major military and defense systems. A statistical ...
Beck, Derek William, 1977-
Predictions of thermal comfort and pollutant distributions for a thermostatically-controlled, air-conditioned, partitioned room: Numerical results and enhanced graphical presentation
An index of local thermal comfort and pollutant distributions have been computed with the TEMPEST computer code, in a transient simulation of an air-conditioned enclosure with an incomplete partition. This complex three-dimensional air conditioning problem included forced ventilation through inlet veins, flow through a partition, remote return air vents, and infiltration source, a pollutant source, and a thermostatically controlled air conditioning system. Five forced ventilation schemes that varied in vent areas and face velocities were simulated. Thermal comfort was modeled as a three-dimensional scalar field dependent on the fluid velocity and temperature fields; where humidity activity levels, and clothing were considered constants. Pollutants transport was incorporated through an additional constituent diffusion equation. Six distinct graphic techniques for the visualization of the three-dimensional data fields of air velocity, temperature, and comfort index were tested. 4 refs., 7 figs., 1 tab.
White, M.D.; Eyler, L.L.
Problem of Vain Energy Consumption in a VAV Air Conditioning System Shared By an Inner Zone and Exterior Zone
In northern China, there are a large number of space buildings divided in inner zone and exterior zone based on usage requirements. The exterior zone needs to be heated in winter and cooled in summer, while the inner zone needs to be cooled both in winter and summer. Taking a practical project as example, this paper analyzes the energy consumption of a VAV air conditioning system that is shared by inner zone and exterior zone. The paper also points out the serious problem of useless energy consumption for this kind of system.
Wenji, G.; Ling, C.; Dongdong, L.; Mei, S.; Li, Z.
Field Demonstration of a High-Efficiency Packaged Rooftop Air Conditioning Unit at Fort Gordon, Augusta, GA
As part of a larger program targeting the market transformation of packaged rooftop air conditioning, five high-efficiency rooftop air conditioning products were selected in 2002 by the U.S. Department of Energy (DOE) under the Unitary Air Conditioner (UAC) Technology Procurement (http://www.pnl.gov/uac). In February 2003, Fort Gordon in Augusta, Georgia was chosen as the demonstration site. With the goal of validating the field performance and operation of one of the awarded products, a 10-ton high-efficiency packaged rooftop unit (RTU) manufactured by Global Energy Group (GEG) was installed at Fort Gordon in October 2003. Following equipment installation, power metering, air- and refrigerant-side instrumentation was installed on the GEG RTU and a 4-year old typical-efficiency 20-ton RTU manufactured by AAON . The GEG and AAON units were instrumented identically and operated May through July, 2005, to observe performance under a range of conditions. Based on the data collected as part of this demonstration, the GEG equipment performed at least 8% better in stage-1 (single compressor running) cooling and at least 16% better in stage-2 (both compressors running) than the baseline AAON equipment. Performance comparisons are based on what we call application EER normalized to equivalent specific fan power. The full-load, specific-fan-power-normalized application EERs at ARI design conditions were 10.48 Btu/Wh for the GEG and 9.00 Btu/Wh for the baseline machine. With a cost premium of nearly 50%, and slightly higher maintenance costs, the life-cycle cost analysis shows that the GEG technology pays for itself--a positive net-present value (NPV)--only in climates and buildings with long cooling seasons. Manufacture of this equipment on a larger scale can be expected to reduce costs to the point where it is more broadly cost-effective. The assumed 10-ton baseline and new-technology unit costs are $3824.00 and $5525.00 respectively. If the new technology cost is assumed to drop as sales increase to $4674.50 for a 10-ton unit (i.e. the original cost difference is halved), the life-cycle costs improve. A grid of first cost, annual maintenance cost and electricity price is enumerated and the results presented in the report show the sensitivity of life cycle cost to these three financial parameters in each of eight different climates.
Armstrong, Peter R.; Sullivan, Gregory P.; Parker, Graham B.
An update on acoustics designs for HVAC (Engineering) K. Marriott
An update on acoustics designs for HVAC (Engineering) K. Marriott IOA, 29a Ashburton Road, Croydon and Air Conditioning (HVAC) engineer is to engineer ways for keeping these factors under control the HVAC engineer's environmental requirements while minimizing noise generated in the process considering
Preoperational Subsurface Conditions at the Idaho Nuclear Technology and Engineering Center Service Wastewater Discharge Facility
The Idaho Nuclear Technology and Engineering Center (INTEC) Service Wastewater Discharge Facility replaces the existing percolation ponds as a disposal facility for the INTEC Service Waste Stream. A preferred alternative for helping decrease water content in the subsurface near INTEC, closure of the existing ponds is required by the INTEC Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) Record of Decision (ROD) for Waste Area Group 3 Operable Unit 3-13 (DOE-ID 1999a). By August 2002, the replacement facility was constructed approximately 2 miles southwest of INTEC, near the Big Lost River channel. Because groundwater beneath the Idaho National Engineering and Environmental Laboratory (INEEL) is protected under Federal and State of Idaho regulations from degradation due to INEEL activities, preoperational data required by U.S. Department of Energy (DOE) Order 5400.1 were collected. These data include preexisting physical, chemical, and biological conditions that could be affected by the discharge; background levels of radioactive and chemical components; pertinent environmental and ecological parameters; and potential pathways for human exposure or environmental impact. This document presents specific data collected in support of DOE Order 5400.1, including: four quarters of groundwater sampling and analysis of chemical and radiological parameters; general facility description; site specific geology, stratigraphy, soils, and hydrology; perched water discussions; and general regulatory requirements. However, in order to avoid duplication of previous information, the reader is directed to other referenced publications for more detailed information. Documents that are not readily available are compiled in this publication as appendices. These documents include well and borehole completion reports, a perched water evaluation letter report, the draft INEEL Wellhead Protection Program Plan, and the Environmental Checklist.
Ansley, Shannon L.
Enhanced air/fuel mixing for automotive stirling engine turbulator-type combustors
The invention relates to the improved combustion of fuel in a combustion chamber of a stirling engine and the like by dividing combustion into primary and secondary combustion zones through the use of a diverter plate.
Riecke, George T. (Ballston Spa, NY); Stotts, Robert E. (Newark, NY)
Smart Operations of Air-Conditioning and Lighting Systems in a Government Buildings for Peak Power Reduction
This paper presents the achievements of implementing smart operations strategies for air-conditioning (A/C) and lighting systems in Justice Palace Complex (JPC), Kuwait during the summer 2007. The peak load of this building was 3700 kW. The achievements are summarized as direct savings between 13:00 and 22:00 h by closing supply and return air fans of 52 air-handling units with a connected load 400 kW, and an additional saving of 550 kW during the same period by optimizing the cooling production and distribution. Also an all time saving of 22 kW by de-lamping, and additional saving of 27 kW through TDC of lighting were achieved. In conclusion project achieved an overall reduction in power demand of around 20% between 13:00 to 17:00 h and reduction ranging from 7% to 15% between 17:00 to 20:00 h.
Energy and economic performance analysis of an open cycle solar desiccant dehumidification air-conditioning system for application in Hong Kong
In this article, a transient simulation model and the EnergyPlus were used to study the energy performance and economical feasibility for integrating a solar liquid desiccant dehumidification system with a conventional vapor compression air-conditioning system for the weather condition of Hong Kong. The vapor compression system capacity in the solar assisted air-conditioning system can be reduced to 19 kW from original 28 kW of a conventional air-conditioning system as a case study due to the solar desiccant cooling. The economical performance of the solar desiccant dehumidification system is compared with that of the conventional air-conditioning system. The results show that the energy saving potentials due to incorporation of the solar desiccant dehumidification system in a traditional air-conditioning system is significant for the hot wet weather in Hong Kong due to higher COP resulted from higher supply chilled water temperature from chiller plants. The annual operation energy savings for the hybrid system is 6760 kWh and the payback period of the hybrid system is around 7 years. The study shows that the solar assisted air-conditioning is a viable technology for utilizations in subtropical areas. (author)
Li, Yutong; Lu, Lin; Yang, Hongxing [Renewable Energy Research Group (RERG), Department of Building Services Engineering, Hong Kong Polytechnic University, Hung Hom (China)
Distortions of Experimental Muon Arrival Time Distributions of Extensive Air Showers by the Observation Conditions
Event-by-event measured arrival time distributions of Extensive Air Shower (EAS) muons are affected and distorted by various interrelated effects which originate from the time resolution of the timing detectors, from fluctuations of the reference time and the number (multiplicity) of detected muons spanning the arrival time distribution of the individual EAS events. The origin of these effects is discussed, and different correction procedures, which involve detailed simulations, are proposed and illustrated. The discussed distortions are relevant for relatively small observation distances (R < 200 m) from the EAS core. Their significance decreases with increasing observation distance and increasing primary energies. Local arrival time distributions which refer to the observed arrival time of the first local muon prove to be less sensitive to the mass of the primary. This feature points to the necessity of arrival time measurements with additional information on the curvature of the EAS disk.
R. Haeusler; A. F. Badea; H. Rebel; I. M. Brancus; J. Oehlschlaeger
Simulations of Mesoscale Circulations in the Center of the Iberian Peninsula for Thermal Low Pressure Conditions. Part II: Air-Parcel Transport Patterns
This paper discusses the variability of air-parcel transport under similar summer thermal low pressure conditions over the Iberian Peninsula. Three-dimensional trajectories were estimated by means of the Topography Vorticity-Mode Mesoscale model. ...
Fernando Mart�n; Magdalena Palacios; Sylvia N. Cresp�
Fuzzy expert system design for operating room air-condition control systems
In this study, a controlled fuzzy expert system (FES) was designed to provide the conditions necessary for operating rooms. For this purpose, existing operating rooms have been studied to see if there are more useful, reliable and comfortable ones. How ... Keywords: Adaptive fuzzy control, Expert systems, Fuzzy control systems, Operating room control
Nazmi Etik; Novruz Allahverdi; Ibrahim Unal Sert; Ismail Saritas
The absorbent's solution flow process, non-parametric identification into an absorption chiller for air conditioning
The lithium bromide chillers supplied from solar collectors are used to provide proper environmental conditions into industrial and civil buildings. To maintain the appropriate values for the temperature into the chiller's boiler, a control unit is introduced ... Keywords: absorption chiller, flow process, system identification
Adrian Danila
Japanese and American competition in the development of scroll compressors and its impact on the American air conditioning industry
This report examines the technological development of scroll compressors and its impact on the air conditioning equipment industry. Scroll compressors, although considered to be the compressors of the future for energy-efficient residential heat pumps and possibly for many other applications, are difficult to manufacture on a volume-production base. The manufacturing process requires computer-aided, numerically controlled tools for high-precision fabrication of major parts. Japan implemented a global strategy for dominating the technological world market in the 1970s, and scroll compressor technology benefited from the advent of new-generation machine tools. As a result, if American manufacturers of scroll compressors purchase or are essentially forced to purchase numerically controlled tools from Japan in the future, they will then become dependent on their own competitors because the same Japanese conglomerates that make numerically controlled tools also make scroll compressors. This study illustrates the importance of the basic machine tool industry to the health of the US economy. Without a strong machine tool industry, it is difficult for American manufacturers to put innovations, whether patented or not, into production. As we experience transformation in the air conditioning and refrigeration market, it will be critical to establish a consistent national policy to provide healthy competition among producers, to promote innovation within the industry, to enhance assimilation of new technology, and to eliminate practices that are incompatible with these goals. 72 refs., 8 figs., 1 tab.
Ushimaru, Kenji (Energy International, Inc., Bellevue, WA (USA))
Air-conditioning electricity savings and demand reductions from exterior masonry wall insulation applied to Arizona residences
A field test involving eight single-family houses was performed during the summer of 1991 in Scottsdale, Arizona to evaluate the potential of reducing air-conditioning electricity consumption and demand by insulating their exterior masonry walls. Total per house costs to perform the installations ranged from $3610 to $4550. The average annual savings was estimated to be 491 kWh, or 9% of pre-retrofit consumption. Peak demands without and with insulation on the hottest day of an average weather year for Phoenix were estimated to be 4.26 and 3.61 kill, for a demand reduction of 0.65 kill (15%). We conclude that exterior masonry wall insulation reduces air-conditioning electricity consumption and peak demand in hot, dry climates similar to that of Phoenix. Peak demand reductions are a primary benefit, making the retrofit worthy of consideration in electric utility conservation programs. Economics can be attractive from a consumer viewpoint if considered within a renovation or home improvement program.
Ternes, M.P.; Wilkes, K.E.
Deliberate ignition of hydrogen-air-steam mixtures under conditions of rapidly condensing steam
A series of experiments was conducted to determine hydrogen combustion behavior under conditions of rapidly condensing steam caused by water sprays. Experiments were conducted in the Surtsey facility under conditions that were nearly prototypical of those that would be expected in a severe accident in the CE System 80+ containment. Mixtures were initially nonflammable owing to dilution by steam. The mixtures were ignited by thermal glow plugs when they became flammable after sufficient steam was removed by condensation caused by water sprays. No detonations or accelerated flame propagation was observed in the Surtsey facility. The combustion mode observed for prototypical mixtures was characterized by multiple deflagrations with relatively small pressure rises. The thermal glow plugs were effective in burning hydrogen safely by igniting the gases as the mixtures became marginally flammable.
Blanchat, T.; Stamps, D.
Actinide leaching from waste glass: air-equilibrated versus deaerated conditions
Leach tests were conducted in aerated and deaerated solutions using glass containing /sup 239/Pu, /sup 237/Np and /sup 238/U, at temperatures of 25 and 75/sup 0/C and in deionized water, 0.03M NaHCO/sub 3/ and WIPP B salt brine for periods up to 341 days. Neptunium leaching was decreased by factors of 10 to 100 (depending on leach time) in the deaerated solutions at 75/sup 0/C. Plutonium leaching decreased by factors of 3 to 5 due to deaeration, but only in the deionized water leachate at 25/sup 0/C. Uranium leaching in salt brine and deionized water at 25/sup 0/C was decreased by factors of 2 to 5 in deaerated solutions. Time and temperature dependencies were also observed for the leaching of the actinides during the course of this work. After the first leach interval (2 days), the time dependent release curve for Pu was essentially flat or decreasing under all conditions, and maximum Pu solution concentration (at 25/sup 0/C), as implied by release in aerated leachate, agrees with independent solubility data. The low /sup 239/Pu releases observed in leach solutions are consistent with accumulation of /sup 239/Pu on the leached glass surface. The amounts of uranium and neptunium leached increased with time under most conditions. For Pu leaching, temperature has a small effect in deaerated leachates and negative effect in aerated leachates. Neptunium leaching generally increase with temperature under aerated conditions, but not in proportion to increases of matrix element leaching. In deaerated leachates, Np leaching decreases with temperature. Uranium leaching increases with temperature under aerated and deaerated conditions but not in proportion to matrix element increases. 4 figures, 6 tables.
Peters, R.D.; Diamond, H.
Study of the test method for prediction of air conditioning equipment seasonal performance
The test procedure, Method of Testing, Rating and Estimating the Seasonal Performance of Central Air-Conditioners and Heat Pumps Operating in the Cooling Mode, has been analyzed. The analysis of the test procedure incorporated two main functions: (1) to determine the validity of the test procedure; and (2) to determine if there are other alternate methods of obtaining the same results with less testing burden. Data were collected from industry and analyzed for any significant trends. Certain conclusions are drawn about the energy efficiency ratios, degradation coefficients and seasonal energy efficiency ratios. An error analysis was performed on the test procedure to determine the approximate amount of error when using this procedure. A semi-empirical model assuming a first order system response was developed to determine the factors that affect the part-load and cooling-load factors. The corresponding transient characteristics are then determined in terms of a single time constant. A thermostat demand cycle is used to determine the relationship between on-time and cycle-time. Recommendations are made regarding an alternate method being used to determine the seasonal energy efficiency ratio.
Thomas, S.B.
The effect of hardware configuration on the performance of residential air conditioning systems at high outdoor ambient temperatures
A study was performed which investigated the effect of hardware configuration on air conditioning cooling system performance at high outdoor temperatures. The initial phase of the investigation involved the testing of ten residential air conditioning units in psychrometric rooms at Texas A&M University. All units were tested using ARI Standard 210/240 (1989) test procedures. Tests were conducted at indoor conditions of 80'F (26.7'C) db and 67'F (19.4'C) wb, and outdoor db temperatures of 82'F (27.8'C), 95-F (35-C), 100-F (37.8-C), 105-F (40.6-C), 1 10-F (43.3-C), and 120-F (48.90C). The second phase of the research involved the analysis of manufacturers' published cooling performance data for various hardware configurations. For the experimental work, measurements were taken to determine total capacity, system power, EER, and power factor. These results were then compared to manufacturers' predicted values. For the capacity, the experimental results were an average of 2.6% below the manufacturers' published values for outdoor temperatures from 85'F (29.4'C) to 115'F (46.l'C). Experimental power measurements were on average 0.4% above manufacturers' listed results. For the EER, experimental results were an average of 2.9% less than the manufacturers' predicted values. The power factors of all units were above 0.95 for the tested outdoor temperatures. In the analysis of manufacturers' published data, relationships between steady-state performance, cyclic performance, and hardware configuration were investigated for a variety of air conditioning units. A statistical relationship was found between the SEER of a unit and its corresponding EER. The split-system units possessed greater increases in EER for a given increase in SEER than the package or two-speed units. Averages values of EER/SEER for EER's at 95F (350C) were highest for the split-system units, followed by the package and two-speed units, respectively. Normalized capacity, power, and EER curves were investigated at outdoor temperatures from 85F (29.40C) to 115OF (46.1"C). On average, the two-speed units showed the smallest decrease in capacity with an increase in outdoor temperature, followed by the split-system and package-system units. The smallest power increase and smallest EER decrease with an increase in outdoor temperature were exhibited by the split-system units, followed by the two-speed and package-system units.
Bain, Joel Alan
Combustion lean limits fundamentals and their application to a SI hydrogen-enhanced engine concept
Operating an engine with excess air, under lean conditions, has significant benefits in terms of increased engine efficiency and reduced emissions. However, under high dilution levels, a lean limit is reached where combustion ...
Ayala, Ferran A. (Ferran Alberto), 1976-
Influence of Attic Radiant Barrier Systems on Air Conditioning Demand in an Utility Pilot Project
A utility monitoring project has evaluated radiant barrier systems (RBS) as a new potential demand site management (DSM) program. The study examined how the retrofit of attic radiant barriers can be expected to alter utility residential space conditioning loads. An RBS consists of a layer of aluminum foil fastened to roof decking or roof trusses to block radiant heat transfer between the hot roof surface and the attic below. The radiant barrier can significantly lower summer heat transfer to the attic insulation and to the cooling duct system. Both of these mechanisms have strong potential impacts on cooling energy use as illustrated in Figures 1 and 2. The pilot project involved installation of RBS in nine homes that had been extensively monitored over the preceding year. The houses varied in conditioned floor area from 939 to 2,440 square feet; attic insulation varied from R-9 to R-30. The homes had shingle roofs with varying degrees of attic ventilation. The radiant barriers were installed during the summer of 2000. Data analysis on the pre and post cooling and heating consumption was used to determine impacts on energy use and peak demand for the utility. The average cooling energy savings from the RBS retrofit was 3.6 kWh/day, or about 9%. The average reduction in summer afternoon peak demand was 420 watts (or about 16%).
Parker, D. S.; Sherwin, J. R.
Experimental evaluation of oxygen-enriched air and emulsified fuels in a single-cylinder diesel engine
The performance of a single-cylinder, direct-injection diesel engine was measured with intake oxygen levels of up to 35% and fuel water contents of up to 20%. Because a previous study indicated that the use of a less-expensive fuel would be more economical, two series of tests with No. 4 diesel fuel and No. 2 diesel fuel were conducted. To control the emissions of nitrogen oxides (NO{sub x}), water was introduced into the combustion process in the form of water-emulsified fuel, or the fuel injection timing was retarded. In the first series of tests, compressed oxygen was used; in the second series of tests, a hollow-tube membrane was used. Steady-state engine performance and emissions data were obtained. Test results indicated a large increase in engine power density, a slight improvement in thermal efficiency, and significant reductions in smoke and particulate-matter emissions. Although NO{sub x} emissions increased, they could be controlled by introducing water and retarding the injection timing. The results further indicated that thermal efficiency is slightly increased when moderately water-emulsified fuels are used, because a greater portion of the fuel energy is released earlier in the combustion process. Oxygen-enriched air reduced the ignition delay and caused the heat-release rate and cumulative heat-release rates to change measurably. Even at higher oxygen levels, NO{sub x} emissions decreased rapidly when the timing was retarded, and the amount of smoke and the level of particulate-matter emissions did not significantly increase. The single-cylinder engine tests confirmed the results of an earlier technical assessment and further indicated a need for a low-pressure-drop membrane specifically designed for oxygen enrichment. Extension data set indexed separately. 14 refs.
Sekar, R.R.; Marr, W.W.; Cole, R.L.; Marciniak, T.J.
Influences of atmospheric conditions and air mass on the ratio of ultraviolet to total solar radiation
The technology to detoxify hazardous wastes using ultraviolet (UV) solar radiation is being investigated by the DOE/SERI Solar Thermal Technology Program. One of the elements of the technology evaluation is the assessment and characterization of UV solar radiation resources available for detoxification processes. This report describes the major atmospheric variables that determine the amount of UV solar radiation at the earth's surface, and how the ratio of UV-to-total solar radiation varies with atmospheric conditions. These ratios are calculated from broadband and spectral solar radiation measurements acquired at SERI, and obtained from the literature on modeled and measured UV solar radiation. The following sections discuss the atmospheric effects on UV solar radiation and provide UV-to-total solar radiation ratios from published studies, as well as measured values from SERI's data. A summary and conclusions are also given.
Riordan, C.J.; Hulstrom, R.L.; Myers, D.R.
Quantitative planar laser-induced fluorescence imaging of multi-component fuel/air mixing in a firing gasoline-direct-injection engine: Effects of residual exhaust gas on quantitative PLIF
A study of in-cylinder fuel-air mixing distributions in a firing gasoline-direct-injection engine is reported using planar laser-induced fluorescence (PLIF) imaging. A multi-component fuel synthesised from three pairs of components chosen to simulate light, medium and heavy fractions was seeded with one of three tracers, each chosen to co-evaporate with and thus follow one of the fractions, in order to account for differential volatility of such components in typical gasoline fuels. In order to make quantitative measurements of fuel-air ratio from PLIF images, initial calibration was by recording PLIF images of homogeneous fuel-air mixtures under similar conditions of in-cylinder temperature and pressure using a re-circulation loop and a motored engine. This calibration method was found to be affected by two significant factors. Firstly, calibration was affected by variation of signal collection efficiency arising from build-up of absorbing deposits on the windows during firing cycles, which are not present under motored conditions. Secondly, the effects of residual exhaust gas present in the firing engine were not accounted for using a calibration loop with a motored engine. In order to account for these factors a novel method of PLIF calibration is presented whereby 'bookend' calibration measurements for each tracer separately are performed under firing conditions, utilising injection into a large upstream heated plenum to promote the formation of homogeneous in-cylinder mixtures. These calibration datasets contain sufficient information to not only characterise the quantum efficiency of each tracer during a typical engine cycle, but also monitor imaging efficiency, and, importantly, account for the impact of exhaust gas residuals (EGR). By use of this method EGR is identified as a significant factor in quantitative PLIF for fuel mixing diagnostics in firing engines. The effects of cyclic variation in fuel concentration on burn rate are analysed for different fuel injection strategies. Finally, mixture distributions for late injection obtained using quantitative PLIF are compared to predictions of computational fluid dynamics calculations. (author)
Williams, Ben; Ewart, Paul [Department of Physics, Oxford University, Parks Road, Oxford OX1 3PU (United Kingdom); Wang, Xiaowei; Stone, Richard [Department of Engineering Science, Oxford University, Parks Road, Oxford OX1 3PJ (United Kingdom); Ma, Hongrui; Walmsley, Harold; Cracknell, Roger [Shell Global Solutions (UK), Shell Research Centre Thornton, P. O. Box 1, Chester, CH1 3SH (United Kingdom); Stevens, Robert; Richardson, David; Fu, Huiyu; Wallace, Stan [Jaguar Cars, Engineering Centre, Abbey Road, Whitley, Coventry, CV3 4LF (United Kingdom)
Advanced control strategies for heating, ventilation, air-conditioning, and refrigeration systems�An overview: Part I: Hard control
A chronological overview of the advanced control strategies for heating, ventilation, air-conditioning, and refrigeration (HVAC&R) is presented in this article. The overview focuses on hard-computing or control techniques, such as proportional-integral-derivative, optimal, nonlinear, adaptive, and robust; soft-computing or control techniques, such as neural networks, fuzzy logic, genetic algorithms; and on the fusion or hybrid of hard- and soft-control techniques. Thus, it is to be noted that the terminology �hard� and �soft� computing/control has nothing to do with the �hardware� and �software� that is being generally used. Part I of a two-part series focuses on hard-control strategies, and Part II focuses on softand fusion-control in addition to some future directions in HVAC&R research. This overview is not intended to be an exhaustive survey on this topic, and any omission of other works is purely unintentional.
D. Subbaram Naidu; Craig G. Rieger
Comment submitted by the Air Conditioning, Heating and Refrigeration Institute (AHRI) regarding the Energy Star Verification Testing Program
AHRI Comments - DOE Verification Testing in Support of Energy Star AHRI Comments - DOE Verification Testing in Support of Energy Star May 9, 2011 P a g e | 1 May 9, 2010 Ms. Ashley Armstrong U.S. Department of Energy 1000 Independence Avenue, SW Washington, DC 20585 RE: DOE Verification Testing in Support of Energy Star Dear Ms. Armstrong: I am writing on behalf of the Air Conditioning, Heating and Refrigeration Institute (AHRI) to address the proposed DOE requirements for verification testing in support of the Energy Star program. AHRI is the trade association representing manufacturers of heating, cooling, and commercial refrigeration equipment. More than 300 members strong, AHRI is an internationally recognized advocate for the industry, and develops standards for and certifies the performance of many of the
1997 Idaho National Engineering and Environmental Laboratory (INEEL) National Emission Standards for Hazardous Air Pollutants (NESHAPs) -- Radionuclides annual report
Under Section 61.94 of Title 40, Code of Federal Regulations (CFR), Part 61, Subpart H, National Emission Standards for Emissions of Radionuclides Other Than Radon From Department of Energy Facilities, each Department of Energy (DOE) facility must submit an annual report documenting compliance. This report addresses the Section 61.94 reporting requirements for operations at the Idaho National Engineering and Environmental Laboratory (INEEL) for calendar year (CY) 1997. Section 1 of this report provides an overview of the INEEL facilities and a brief description of the radioactive materials and processes at the facilities. Section 2 identifies radioactive air effluent release points and diffuse sources at the INEEL and actual releases during 1997. Section 2 also describes the effluent control systems for each potential release point. Section 3 provides the methodology and EDE calculations for 1997 INEEL radioactive emissions.
Copper contamination effects on hydrogen-air combustion under SCRAMJET (supersonic combustion ramjet) testing conditions
Two forms of copper catalytic reactions (homogeneous and heterogeneous) in hydrogen flames were found in a literature survey. Hydrogen atoms in flames recombine into hydrogen molecules through catalytic reactions, and these reactions which affect the timing of the combustion process. Simulations of hydrogen flames with copper contamination were conducted by using a modified general chemical kinetics program (GCKP). Results show that reaction times of hydrogen flames are shortened by copper catalytic reactions, but ignition times are relatively insensitive to the reactions. The reduction of reaction time depends on the copper concentration, copper phase, particle size (if copper is in the condensed phase), and initial temperature and pressure. The higher the copper concentration of the smaller the particle, the larger the reduction in reaction time. For a supersonic hydrogen flame (Mach number = 4.4) contaminated with 200 ppm of gaseous copper species, the calculated reaction times are reduced by about 9%. Similar reductions in reaction time are also computed for heterogeneous copper contamination. Under scramjet testing conditions, the change of combustion timing appears to be tolerable (less than 5%) if the Mach number is lower than 3 or the copper contamination is less than 100 ppm. The higher rate the Mach number, the longer the reaction time and the larger the copper catalytic effects. 7 tabs., 8 figs., 34 refs.
Chang, S.L.; Lottes, S.A.; Berry, G.F.
High Efficiency Integrated Space Conditioning, Water Heating and Air Distribution System for HUD-Code Manufactured Housing
Recognizing the need for new space conditioning and water heating systems for manufactured housing, DeLima Associates assembled a team to develop a space conditioning system that would enhance comfort conditions while also reducing energy usage at the systems level. The product, Comboflair® was defined as a result of a needs analysis of project sponsors and industry stakeholders. An integrated system would be developed that would combine a packaged airconditioning system with a small-duct, high-velocity air distribution system. In its basic configuration, the source for space heating would be a gas water heater. The complete system would be installed at the manufactured home factory and would require no site installation work at the homesite as is now required with conventional split-system air conditioners. Several prototypes were fabricated and tested before a field test unit was completed in October 2005. The Comboflair® system, complete with ductwork, was installed in a 1,984 square feet, double-wide manufactured home built by Palm Harbor Homes in Austin, TX. After the home was transported and installed at a Palm Harbor dealer lot in Austin, TX, a data acquisition system was installed for remote data collection. Over 60 parameters were continuously monitored and measurements were transmitted to a remote site every 15 minutes for performance analysis. The Comboflair® system was field tested from February 2006 until April 2007. The cooling system performed in accordance with the design specifications. The heating system initially could not provide the needed capacity at peak heating conditions until the water heater was replaced with a higher capacity standard water heater. All system comfort goals were then met. As a result of field testing, we have identified improvements to be made to specific components for incorporation into production models. The Comboflair® system will be manufactured by Unico, Inc. at their new production facility in St. Louis, MO. The product will be initially launched in the hot-humid climates of the southern U.S.
Henry DeLima; Joe Akin; Joseph Pietsch
A full scale 15 deg sector of the P122 reactor configuration was constructed. The model was complete with respect to all internal cooling air passages, and reflectors, thermal shielding, and island reflector. The contract was terminated before any test data could be obtained. Investigation of the effect of atmospheric dust on performance of reactor systems using wire screen matrix fuel elements is reported. The interim conclusion is that dust would not limit aircraft performance or life. Work proposed but not completed is outlined. Appendices contain previously unpublished reports. (auth)
Venneman, W.F.; Lawrence, R.L.; Ryan, P.T.
Conceputual design of a solar-heated-air receiver coupled to a Brayton or Stirling engine
A particularly interesting possibility for a parabolic dish/cavity receiver combination is the coupling of the cavity to a Stirling or Brayton engine. The design of the receiver is a pacing item in the development of the approach and requires knowledge of the flux distribution within the receiver. Thus several cavity configurations need to be considered to ascertain the trade-offs between cavity geometry and flux distribution. Simple analytical tools developed are applied to the analysis and design of a dome-capped cylindrical receiver that has desirable characteristics for transferring heat to a Dish/Brayton or Dish/Stirling system.
Hamilton, N. I.; Jarvinen, P. O.
Using Acid Number as a Leading Indicator of Refrigeration and Air Conditioning System Performance
This report summarizes a literature review to assess the acidity characteristics of the older mineral oil and newer polyolester (POE) refrigeration systems as well as to evaluate acid measuring techniques used in other non-aqueous systems which may be applicable for refrigeration systems. Failure in the older chlorofluorocarbon/hydrochlorofluorocarbon (CFC/HCFC) / mineral oil systems was primarily due to thermal degradation of the refrigerant which resulted in the formation of hydrochloric and hydrofluoric acids. These are strong mineral acids, which can, over time, severely corrode the system metals and lead to the formation of copper plating on iron surfaces. The oil lubricants used in the older systems were relatively stable and were not prone to hydrolytic degradation due to the low solubility of water in oil. The refrigerants in the newer hydrofluorocarbon (HFC)/POE systems are much more thermally stable than the older CFC/HCFC refrigerants and mineral acid formation is negligible. However, acidity is produced in the new systems by hydrolytic decomposition of the POE lubricants with water to produce the parent organic acids and alcohols used to prepare the POE. The individual acids can therefore vary but they are generally C5 to C9 carboxylic acids. Organic acids are much weaker and far less corrosive to metals than the mineral acids from the older systems but they can, over long time periods, react with metals to form carboxylic metal salts. The salts tend to accumulate in narrow areas such as capillary tubes, particularly if residual hydrocarbon processing chemicals are present in the system, which can lead to plugging. The rate of acid production from POEs varies on a number of factors including chemical structure, moisture levels, temperature, acid concentration and metals. The hydrolysis rate of reaction can be reduced by using driers to reduce the free water concentration and by using scavenging chemicals which react with the system acids. Total acid number (TAN), which includes both mineral acids and organic acids, is therefore a useful indicator which can be used to monitor the condition of the system in order to perform remedial maintenance, when required, to prevent system failure. The critical TAN value is the acid level at which remedial action should be taken to prevent the onset of rapid acid formation which can result in system failure. The level of 0.05 mg KOH/g of oil was established for CFC/mineral oil systems based on analysis of 700 used lubricants from operating systems and failed units. There is no consensus within the refrigeration industry as to the critical TAN value for HFC/POE systems, however, the value will be higher than the CFC/mineral oil systems critical TAN value because of the much weaker organic acids produced from POE. A similar study of used POE lubricants should be performed to establish a critical TAN limit for POE systems. Titrimetric analysis per ASTM procedures is the most commonly used method to determine TAN values in lubricants in the refrigeration industry and other industries dealing with lubricating oils. For field measurements, acid test kits are often used since they provide rapid, semi-quantitative TAN results.
Dennis Cartlidge; Hans Schellhase
NRELs Energy-Saving Technology for Air Conditioning Cuts Peak Power Loads Without Using Harmful Refrigerants (Fact Sheet), NREL (National Renewable Energy Laboratory)
DEVAP Slashes Peak Power Loads DEVAP Slashes Peak Power Loads Desiccant-enhanced evaporative (DEVAP) air-condi- tioning will provide superior comfort for commercial buildings in any climate at a small fraction of the elec- tricity costs of conventional air-conditioning equip- ment, releasing far less carbon dioxide and cutting costly peak electrical demand by an estimated 80%. Air conditioning currently consumes about 15% of the electricity generated in the United States and is a major contributor to peak electrical demand on hot summer days, which can lead to escalating power costs, brownouts, and rolling blackouts. DEVAP employs an innovative combination of air-cooling technologies to reduce energy use by up to 81%. DEVAP also shifts most of the energy needs to thermal energy sources, reducing annual electricity use by up
Modeling the structural behavior of the piston rings under different boundary conditions in internal combustion engines
In the process of designing internal combustion engine, piston ring plays an important role in fulfilling the requirements of camber gas sealing, friction reduction and lubrication oil consumption. The goal of this thesis ...
Xu, Dian
High efficiency stoichiometric internal combustion engine system
A power system including a stoichiometric compression ignition engine in which a roots blower is positioned in the air intake for the engine to control air flow. Air flow is decreased during part power conditions to maintain the air-fuel ratio in the combustion chamber of the engine at stoichiometric, thus enabling the use of inexpensive three-way catalyst to reduce oxides of nitrogen. The roots blower is connected to a motor generator so that when air flow is reduced, electrical energy is stored which is made available either to the roots blower to temporarily increase air flow or to the system electrical load and thus recapture energy that would otherwise be lost in reducing air flow.
Winsor, Richard Edward (Waterloo, IA); Chase, Scott Allen (Cedar Falls, IA)
Systematic method for the condition assessment of central heating plants in Air Force Logistics Command. Master's thesis
Air Force Logistics Command (AFLC), facing decreasing funds and aging utility systems, needed a method to objectively rate its central heating plants. Such a rating system would be used to compare heating plants throughout the command to identify potential problem areas and prioritize major repair projects. This thesis used a Delphi questionnaire to gather opinions from heating plant experts in order to identify and prioritize components considered most critical to overall plant operation. In addition, the experts suggested measurements which could be used to evaluate component conditions. By combining expert opinions and reading from technical literature, component model rating schemes were developed for AFLC's steam and high temperature hot water plants. Based on measurements and observations of critical components in the plant, a score between 0 and 100 is assigned to each component (for example, condensate piping, deaerator, etc.), each plant subsystem (distribution system, water treatment system, etc.), and to the plant as a whole. These component model rating schemes and the resultant overall condition index scores will enable AFLC to focus their management attention and allocate needed resources to the plants in greatest need of repair.
Starmack, G.J.
Impact of Solar Control PVB Glass on Vehicle Interior Temperatures, Air-Conditioning Capacity, Fuel Consumption, and Vehicle Range
The objective of the study was to assess the impact of Saflex1 S-series Solar Control PVB (polyvinyl butyral) configurations on conventional vehicle fuel economy and electric vehicle (EV) range. The approach included outdoor vehicle thermal soak testing, RadTherm cool-down analysis, and vehicle simulations. Thermal soak tests were conducted at the National Renewable Energy Laboratory's Vehicle Testing and Integration Facility in Golden, Colorado. The test results quantified interior temperature reductions and were used to generate initial conditions for the RadTherm cool-down analysis. The RadTherm model determined the potential reduction in air-conditioning (A/C) capacity, which was used to calculate the A/C load for the vehicle simulations. The vehicle simulation tool identified the potential reduction in fuel consumption or improvement in EV range between a baseline and modified configurations for the city and highway drive cycles. The thermal analysis determined a potential 4.0% reduction in A/C power for the Saflex Solar PVB solar control configuration. The reduction in A/C power improved the vehicle range of EVs and fuel economy of conventional vehicles and plug-in hybrid electric vehicles.
Rugh, J.; Chaney, L.; Venson, T.; Ramroth, L.; Rose, M.
Engineering Engineering Engineering1354608000000EngineeringSome of these resources are LANL-only and will require Remote Access./No/Questions? firstname.lastname@example.com Engineering Some of these resources are LANL-only and will require Remote Access. Key Resources Reference Standards Data Sources Organizations Journals Key Resources Engineering Village Includes Engineering Index (Ei) and Compendex Knovel Handbooks, databases, and eBooks integrated with analytical and search tools IEEE Xplore Full text access to technical literature, standards, and conference proceedings in engineering and technology SPIE Digital Library Full-text papers from SPIE journals and proceedings published since 1998; subject coverage includes optics, photonics, electronic imaging, visual information processing, biomedical optics, lasers, and
Electrodynamics Bioscience, Biosecurity, Health Chemical Science Earth, Space Sciences Energy Engineering High Energy Density Plasmas, Fluids Information Science, Computing,...
Automobile air pollution: new automotive engines and engine improvements. 1978-March, 1981 (Citations from the NTIS data base). Report for 1978-March 1981
This bibliography cites reports on new designs of automobile engines. The engine types include gas turbines, stratified charged engines, steam engines, hybrid engines using electric motors or flywheels, and rotary engines. Many of these studies also cover the problem of improving fuel economy while lowering emissions. Retrofit devices are excluded. (This updated bibliography contains 205 citations, 58 of which are new entries to the previous edition.)
Automobile air pollution: new automotive engines and engine improvements. Volume 1. 1970-1977 (a bibliography with abstracts). Report for 1970-1977
This bibliography cites reports on new designs of automobile engines. The engine types include gas turbines, stratified charge engines, steam engines, hybrid engines using electric motors or flywheels, and rotary engines. Many of these studies also cover the problem of improving fuel economy while lowering emissions. Retrofit devices are excluded. (This updated bibliography contains 176 abstracts, none of which are new entries to the previous edition.)
Habercom, G.E. Jr
Automobile air pollution: new automotive engines and engine improvements. Volume 2. 1978-March, 1979 (a bibliography with abstracts). Report for 1978-March 1979
This bibliography cites reports on new designs of automobile engines. The engine types include gas turbines, stratified charged engines, steam engines, hybrid engines using electric motors or flywheels, and rotary engines. Many of these studies also cover the problem of improving fuel economy while lowering emissions. Retrofit devices are excluded. (This updated bibliography contains 100 abstracts, 94 of which are new entries to the previous edition.)
Handbook of energy engineering
This book covers the following topics: Fundamentals of energy engineering; Energy economic analysis; Energy auditing and accounting; Electrical system optimization; Waste heat recovery; Utility system optimization; Heating, ventilation, air conditioning, and building system optimization; HVAC equipment; Cogeneration: theory and practice; Control systems; Computer applications; Thermal storage; Passive solar energy systems; and Energy management.
Mehta, D.P.; Thumann, A.
Influence of Air-Conditioning Waste Heat on Air Temperature in Tokyo during Summer: Numerical Experiments Using an Urban Canopy Model Coupled with a Building Energy Model
A coupled model consisting of a multilayer urban canopy model and a building energy analysis model has been developed to investigate the diurnal variations of outdoor air temperature in the office areas of Tokyo, Japan. Observations and numerical ...
Yukitaka Ohashi; Yutaka Genchi; Hiroaki Kondo; Yukihiro Kikegawa; Hiroshi Yoshikado; Yujiro Hirano
Energy Basics: Air Conditioning
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
the same operating principles and basic components as refrigerators. Refrigerators use energy (usually electricity) to transfer heat from the cool interior of the refrigerator to...
Engineering Enzymes in Energy Crops: Conditionally Activated Enzymes Expressed in Cellulosic Energy Crops
Broad Funding Opportunity Announcement Project: Enzymes are required to break plant biomass down into the fermentable sugars that are used to create biofuel. Currently, costly enzymes must be added to the biofuel production process. Engineering crops to already contain these enzymes will reduce costs and produce biomass that is more easily digested. In fact, enzyme costs alone account for $0.50-$0.75/gallon of the cost of a biomass-derived biofuel like ethanol. Agrivida is genetically engineering plants to contain high concentrations of enzymes that break down cell walls. These enzymes can be �switched on� after harvest so they won�t damage the plant while it�s growing.
Use of LIF image acquisition and analysis in developing a calibrated technique for in-cylinder investigation of the spatial distribution of air-to-fuel mixing in direct injection gasoline engines
This paper presents the role of image acquisition and analysis in the development of a new strategy for the calibration of measurements of fuel distribution in gasoline direct injection engines. Images are acquired from a motored experimental engine ... Keywords: LIF, air-to-fuel mixing, gasoline direct injection engine, image analysis, intensified image acquisition, laser-induced fluorescence
Guillaume de Sercey; Graeme Awcock; Morgan Heikal
This paper presents the role of image acquisition and analysis in the development of a new strategy for the calibration of measurements of fuel distribution in gasoline direct injection engines. Images are acquired from a motored experimental engine ... Keywords: Air-to-fuel mixing, Gasoline direct injection engine, Image analysis, Intensified image acquisition, LIF, Laser-induced fluorescence
Deemed Savings Estimates for Legacy Air Conditioning and WaterHeating Direct Load Control Programs in PJM Region
During 2005 and 2006, the PJM Interconnection (PJM) Load Analysis Subcommittee (LAS) examined ways to reduce the costs and improve the effectiveness of its existing measurement and verification (M&V) protocols for Direct Load Control (DLC) programs. The current M&V protocol requires that a PURPA-compliant Load Research study be conducted every five years for each Load-Serving Entity (LSE). The current M&V protocol is expensive to implement and administer particularly for mature load control programs, some of which are marginally cost-effective. There was growing evidence that some LSEs were mothballing or dropping their DLC programs in lieu of incurring the expense associated with the M&V. This project had several objectives: (1) examine the potential for developing deemed savings estimates acceptable to PJM for legacy air conditioning and water heating DLC programs, and (2) explore the development of a collaborative, regional, consensus-based approach for conducting monitoring and verification of load reductions for emerging load management technologies for customers that do not have interval metering capability.
Goldman, Charles
Distribution of small dispersive coal dust particles and absorbed radioactive chemical elements in conditions of forced acoustic resonance in iodine air filter at nuclear power plant
The physical features of distribution of the small dispersive coal dust particles and the adsorbed radioactive chemical elements and their isotopes in the absorber with the granular filtering medium with the cylindrical coal granules were researched in the case of the intensive air dust aerosol stream flow through the iodine air filter (IAF). It was shown that, at the certain aerodynamic conditions in the IAF, the generation of the acoustic oscillations is possible. It was found that the acoustic oscillations generation results in an appearance of the standing acoustic waves of the air pressure (density) in the IAF. In the case of the intensive blow of the air dust aerosol, it was demonstrated that the standing acoustic waves have some strong influences on both: 1) the dynamics of small dispersive coal dust particles movement and their accumulation in the IAF; 2) the oversaturation of the cylindrical coal granules by the adsorbed radioactive chemical elements and their isotopes in the regions, where the antin...
Ledenyov, Oleg P
Research Director, PIER Demand Response Research CenterAssessment of Demand Response & Advanced Metering, staffPower Shortages: Demand Response and its Applications in Air
Engineering analysis of the air pollution regulatory process impacts on the agricultural industry
The EPA press release dated February 23, 2004 states that the three Buckeye Egg Farm facilities had the potential to emit more than a combined total of 1850 tons per year of particulate matter (PM). This number was based on flowrate calculations that were three times higher than those measured as well as a failure to include particle size distributions in the emissions calculations. The annual PM emission for each facility was approximately 35 tons per year. The EPA was unjustified in requiring Buckeye Egg Farm to obtain Title V and PSD permits as the facilities could not have met the thresholds for these permits. Engineers need to be concerned with correctly measuring and calculating emission rates in order to enforce the current regulations. Consistency among regulators and regulations includes using the correct emission factors for regulatory permitting purposes. EPA has adopted AERMOD as the preferred dispersion model for regulatory use on the premise that it more accurately models the dispersion of pollutants near the surface of the Earth than ISCST3; therefore, it is inappropriate to use the same emission factor in both ISCST3 and AERMOD in an effort to equitably regulate PM sources. For cattle feedlots in Texas, the ISCST3 emission factor is 7 kg/1000 hd-day (16 lb/1000 hd-day) while the AERMOD emission factor is 5 kg/1000 hd-day (11 lb/1000 he-day). The EPA is considering implementing a crustal exclusion for the PM emitted by agricultural sources. Over the next five years, it will be critical to determine a definition of crustal particulate matter that researchers and regulators can agree upon. It will also be necessary to develop a standard procedure to determine the crustal mass fraction of particulate matter downwind from a source to use in the regulatory process. It is important to develop a procedure to determine the particulate matter mass fraction of crustal downwind from a source before the crustal exclusion can be implemented to ensure that the exclusion is being used correctly and consistently among all regulators. According to my findings, the mass fraction of crustal from cattle feedlot PM emissions in the Texas High Plains region is 52%.
Lange, Jennifer Marie
1996 Idaho National Engineering and Environmental Laboratory (INEEL) National Emissions Standards for Hazardous Air Pollutants (NESHAPs) -- Radionuclides. Annual report
Under Section 61.94 of Title 40, Code of Federal Regulations (CFR), Part 61, Subpart H, ``National Emission Standards for Emissions of Radionuclides Other Than Radon From Department of Energy Facilities,`` each Department of Energy (DOE) facility must submit an annual report documenting compliance. This report addresses the Section 61.94 reporting requirements for operations at the Idaho National Engineering and Environmental Laboratory (INEEL) for calendar year (CY) 1996. The Idaho Operations Office of the DOE is the primary contact concerning compliance with the National Emission Standards for Hazardous Air Pollutants (NESHAPs) at the INEEL. For calendar year 1996, airborne radionuclide emissions from the INEEL operations were calculated to result in a maximum individual dose to a member of the public of 3.14E-02 mrem (3.14E-07 Sievert). This effective dose equivalent (EDE) is well below the 40 CFR 61, Subpart H, regulatory standard of 10 mrem per year (1.0E-04 Sievert per year).
Particulate matter emissions from a DISI engine under cold-fast-idle conditions for ethanol-gasoline blends
In an effort to build internal combustion engines with both reduced brake-specific fuel consumption and better emission control, engineers developed the Direct Injection Spark Ignition (DISI) engine. DISI engines combine ...
Dimou, Iason
A Relationship between the Bowen Ratio and Sea�Air Temperature Difference under Unstable Conditions at Sea
At the air�sea interface, estimates of evaporation or latent heat flux and the Monin�Obukhov stability parameter require the measurements of dewpoint (Tdew) or wet-bulb temperature, which are not routinely available as compared to those of air (T...
S. A. Hsu
Future Air Conditioning Energy Consumption in Developing Countriesand what can be done about it: The Potential of Efficiency in theResidential Sector
The dynamics of air conditioning are of particular interestto energy analysts, both because of the high energy consumption of thisproduct, but also its disproportionate impact on peak load. This paperaddresses the special role of this end use as a driver of residentialelectricity consumption in rapidly developing economies. Recent historyhas shown that air conditioner ownership can grow grows more rapidly thaneconomic growth in warm-climate countries. In 1990, less than a percentof urban Chinese households owned an air conditioner; by 2003 this numberrose to 62 percent. The evidence suggests a similar explosion of airconditioner use in many other countries is not far behind. Room airconditioner purchases in India are currently growing at 20 percent peryear, with about half of these purchases attributed to the residentialsector. This paper draws on two distinct methodological elements toassess future residential air conditioner 'business as usual' electricityconsumption by country/region and to consider specific alternative 'highefficiency' scenarios. The first component is an econometric ownershipand use model based on household income, climate and demographicparameters. The second combines ownership forecasts and stock accountingwith geographically specific efficiency scenarios within a uniqueanalysis framework (BUENAS) developed by LBNL. The efficiency scenariomodule considers current efficiency baselines, available technologies,and achievable timelines for development of market transformationprograms, such as minimum efficiency performance standards (MEPS) andlabeling programs. The result is a detailed set of consumption andemissions scenarios for residential air conditioning.
Engineering Engineering Lawrence Livermore National Laboratory Home Technologies Core Competencies Showcase Careers Partnerships About Advanced Manufacturing Developing high-performance materials, devices, components, and assemblies enabled by innovative design tools and novel manufacturing techniques Learn more Applied Electromagnetics Supporting the development of electromagnetic systems that are pervasive and paramount to the greater National Security community. Learn more Data Sciences Enabling better decisions through the development and application of state-of-the-art techniques in machine learning, statistics, and decision sciences Learn more Precision Engineering Embracing determinism to guide rigorous design, construction, and metrology of mechatronic systems, instruments, and manufactured components
Shockwave Engine: Wave Disk Engine
Broad Funding Opportunity Announcement Project: MSU is developing a new engine for use in hybrid automobiles that could significantly reduce fuel waste and improve engine efficiency. In a traditional internal combustion engine, air and fuel are ignited, creating high-temperature and high-pressure gases which expand rapidly. This expansion of gases forces the engine�s pistons to pump and powers the car. MSU�s engine has no pistons. It uses the combustion of air and fuel to build up pressure within the engine, generating a shockwave that blasts hot gas exhaust into the blades of the engine�s rotors causing them to turn, which generates electricity. MSU�s redesigned engine would be the size of a cooking pot and contain fewer moving parts�reducing the weight of the engine by 30%. It would also enable a vehicle that could use 60% of its fuel for propulsion.
4-80 Two rigid tanks connected by a valve to each other contain air at specified conditions. The volume of the second tank and the final equilibrium pressure when the valve is opened are to be determined.
. Treating air as an ideal gas, the volume of the second tank and the mass of air in the first tank temperatures and pressures in ideal gas calculations. Using gage pressures would result in pressure drop of 04-40 4-80 Two rigid tanks connected by a valve to each other contain air at specified conditions
Bahrami, Majid
Evaluation of the Relationship between Air and Land Surface Temperature under Clear- and Cloudy-Sky Conditions
Clear and cloudy daytime comparisons of land surface temperature (LST) and air temperature (Tair) were made for 14 stations included in the U.S. Climate Reference Network (USCRN) of stations from observations made from 2003 through 2008. ...
Kevin Gallo; Robert Hale; Dan Tarpley; Yunyue Yu
Analysis of the Window Side Thermal Environment Formed by Air Barrier Technique in Winter Conditions and Its Economy
The air barrier technique applies airflow through a window fan to decrease the heat load of a window surface and avoid dewfall in winter and decrease heat radiation from the window surface in summer. This paper uses numerical simulation to predict the energy-saving potential and thermal comfort of the air barrier technique used in office buildings. It also analyzes the surface temperature of the window by using the simulation software Airpak. According to the results, we can obtain the key control strategy of this technology. It can be found that the air barrier technique, instead of the heating-supply around outside-zone for office building, can avoid dewfall in winter and decrease the cold radiation, which has a great effect on thermal environment around the window. Characteristics such as outer air temperature, indoor load, thermal characteristics of structure, and air-supply parameters through window fans are analyzed in detail to measure their effects on energy consumption, window side environment and PMV values. The paper provides theoretical reference and technical guidance for applying air barrier technology correctly, improving the window side environment and reducing energy consumption.
Huang, C.; Jia, Y.; Liu, L.; Wang, X.
The Elimination of Oxides of Nitrogen from the Exhaust of a diesel Engine using cryogenic air separation
engine. Compact heat laminar flow heat exchangers, that haveheat exchangers would be too large and too expensive for a compact
Manikowski, A.; Noland, G.; Green, M.A.
DOE/EA-1673: Environmental Assessment for Energy Conservation Program for Certain Industrial Equipment: Energy Conservation Standards and Test Procedures for Commercial Heating, Air-Conditioning, and Water-Heating Equipment (July 2009)
3 3 Environmental Assessment for 10 CFR 431 Energy Conservation Program for Certain Industrial Equipment: Energy Conservation Standards and Test Procedures for Commercial Heating, Air- Conditioning, and Water-Heating Equipment July 2009 8-i CHAPTER 8. ENVIRONMENTAL ASSESSMENT TABLE OF CONTENTS 8.1 INTRODUCTION ............................................................................................................... 8-1 8.2 AIR QUALITY ANALYSIS ............................................................................................... 8-1 8.3 AIR POLLUTANT DESCRIPTIONS ................................................................................ 8-1 8.4 AIR QUALITY REGULATIONS ...................................................................................... 8-3
A Study of the Effect of Molecular and Aerosol Conditions in the Atmosphere on Air Fluorescence Measurements at the Pierre Auger Observatory
The air fluorescence detector of the Pierre Auger Observatory is designed to perform calorimetric measurements of extensive air showers created by cosmic rays of above 10^18 eV. To correct these measurements for the effects introduced by atmospheric fluctuations, the Observatory contains a group of monitoring instruments to record atmospheric conditions across the detector site, an area exceeding 3,000 km^2. The atmospheric data are used extensively in the reconstruction of air showers, and are particularly important for the correct determination of shower energies and the depths of shower maxima. This paper contains a summary of the molecular and aerosol conditions measured at the Pierre Auger Observatory since the start of regular operations in 2004, and includes a discussion of the impact of these measurements on air shower reconstructions. Between 10^18 and 10^20 eV, the systematic uncertainties due to all atmospheric effects increase from 4% to 8% in measurements of shower energy, and 4 g/cm^2 to 8 g/cm^...
Internal combustion engine and method for control
In one exemplary embodiment of the invention an internal combustion engine includes a piston disposed in a cylinder, a valve configured to control flow of air into the cylinder and an actuator coupled to the valve to control a position of the valve. The internal combustion engine also includes a controller coupled to the actuator, wherein the controller is configured to close the valve when an uncontrolled condition for the internal engine is determined.
Brennan, Daniel G
Stirling engines
The Stirling engine was invented by a Scottish clergyman in 1816, but fell into disuse with the coming of the diesel engine. Advances in materials science and the energy crisis have made a hot air engine economically attractive. Explanations are full and understandable. Includes coverage of the underlying thermodynamics and an interesting historical section. Topics include: Introduction to Stirling engine technology, Theoretical concepts--practical realities, Analysis, simulation and design, Practical aspects, Some alternative energy sources, Present research and development, Stirling engine literature.
Reader, G.T.; Hooper
Commissioning Tools for Heating/Cooling System in Residence - Verification of Floor Heating System and Room Air Conditioning System Performance
Tools of evaluating the performance of floor heating and room air conditioner are examined as a commissioning tool. Simple method is needed to check these performance while in use by residents, because evaluation currently requires significant time and effort. Therefore, this paper proposes a) two methods of evaluating the floor heating efficiency from the room / crawl space temperature and the energy consumption and b) method of evaluating COP of the room air conditioner from the data measured at the external unit. Case studies in which these tools were applied to actual residences are presented to demonstrate their effectiveness.
Miura, H.; Hokoi, S.; Iwamae, A.; Umeno, T.; Kondo, S.
The Technical and Economical Analysis of a Centralized Air-Conditioning System with Cold Storage Refrigeration in High-Rise Residential Buildings
In recent years, the application of a centralized air-conditioning system (CACS) with cold storage refrigeration in high-rise residential buildings has gradually increased. Due to the large difference between civil residential buildings and commercial buildings, characteristics such as the cooling load in summer and the storey height must be considered in the design of the air-conditioning system, and the cold storage equipment and the cold supplying means must be properly selected. The option of establishing centralized air-conditioning equipment with cold storage and supplying unified cold in high-rise residential buildings is analyzed objectively with technical and economical methods in this paper. It is not true that the option of supplying unified cold can save energy all the time. CACS with cold storage will not always be economical. Based on a 27-floor building, the running costs in summer and the first costs are both compared between CACS with and without cold storage refrigeration. The cold storage method selected will significantly impact the residents.
Xiang, C.; Xie, G.
Comparison of in-cylinder scavenging flows in a two-stroke cycle engine under motored and fired conditions
The in-cylinder flow field of a loop-scavenged, two-stroke engine has been characterized using laser Doppler velocimetry. The radial component of gas velocity was measured along the axis of the cylinder for both motored and fired operation. Measurements were obtained under conditions simulating both crankcase and external blower driven scavenging. Mean profiles of the radial velocity show marked differences in the global flow structure between motored and fired operation for both scavenging methods. These differences persist throughout the scavenging process and survive compression of the fresh charge. Root mean square (rms) velocity fluctuations near TDC were also determined, and significant differences between motored and fired operation are observed. The rms fluctuations are found to correlate well with the mean shear during compression.
Miles, P.C.; Green, R.M.; Witze, P.O.
B. Air Conditioning and Refrigeration Institute (ARI). C. American Society of Mechanical Engineers (ASME). D. Cryogenic Society of America (CSA).
a. Design and specify refrigeration systems and equipment in accordance with "Energy Conservation Standards " stipulated in Section 15010- Basic Mechanical Requirements. b. Every effort should be made to specify equipment which does not require any CFC refrigerants, including R-11, R-12, R113, or
Cooling Tower Sump Filtration System
Indoor sound criteria according to the American Society of Heating, Refrigerating and Air?Conditioning Engineers (ASHRAE)�An introduction
ASHRAE TC?2.6 Sound and Vibration Controltechnical committee has been activity involved with development
With the upcoming ban on the production of R-22 in 2010, residential air-conditioning equipment will need to be redesigned with a more environmentally benign working fluid. R-410a is a strong candidate for replacing R-22. A model of an air-conditioning system with a focus on the finned-tube condenser design details using R-410a as the working fluid is developed. An optimization algorithm is implemented to find the optimal condenser design with various constraints for an efficiency figure of merit. The software developed is appropriate for engineering design use in the air-conditioning industry.
Susan W. Stewart; Kristinn A. Aspelund; Monifa F. Wright; Emma M. Sadler; Sam V. Shelton, Ph.D.
Energy Consumption Simulation and Analysis of Heat Pump Air Conditioning System in Wuhan by the BIN Method
Based on the weather data of a standard year in Wuhan, derived from the data of the latest 15 years, the data for the BIN (temperature and humidity frequency) method of an annual and 8-hour system were calculated. Then the BIN method was adopted to simulate the annual energy consumption of groundwater heat pump systems (GWHPS) for an office building in Wuhan. Its annual energy consumption was obtained and compared with the partner of the air source heat pump systems (ASHPS). The results show that the energy consumption of the former was approximately less 23.3% than that of the latter in summer and 19.1% in winter.
Wen, Y.; Zhao, F.
E-Alerts: Combustion, engines, and propellants (reciprocation and rotating combustion engines). E-mail newsletter
Design, performance, and testing of reciprocating and rotating engines of various configurations for all types of propulsion. Includes internal and external combustion engines; engine exhaust systems; engine air systems components; engine structures; stirling and diesel engines.
Energy Performance Evaluation and Development of Control Strategies for the Air-conditioning System of a Building at Construction Stage
Energy consumption of HVAC systems in commercial buildings takes a great part of the total building energy consumption. Energy performance evaluation plays an important role in building energy efficiency improvement for existing buildings and new buildings. It is also the basis for the retrofitting measure evaluation for existing buildings and the control improvement evaluation of new buildings for building energy performance contracts. In this study, the energy performance evaluation of a super high-rising commercial office building in construction is presented. Alternative control strategies are proposed to improve the energy efficiency based on the current measurements of the original design as well as additional metering instruments as requested. These control strategies mainly involve optimal chiller sequencing control, cooling tower sequencing control, optimal water pressure differential set-point control, AHU supply air static pressure reset control and DCV-based fresh air control, etc. To assess the economic feasibility, the benchmark electricity consumption and the optimal electricity consumption using alternative controls strategies are estimated using dynamic simulations. The results show that the electricity savings using the alternative control strategies can cover the costs of an additional metering system and related software and hardware in about one year.
Wang, S.; Xu, X.; Ma, Z.
International Energy Agency Building Energy Simulation Test and Diagnostic Method for Heating, Ventilating, and Air-Conditioning Equipment Models (HVAC BESTEST); Volume 1: Cases E100-E200
This report describes the Building Energy Simulation Test for Heating, Ventilating, and Air-Conditioning Equipment Models (HVAC BESTEST) project conducted by the Tool Evaluation and Improvement International Energy Agency (IEA) Experts Group. The group was composed of experts from the Solar Heating and Cooling (SHC) Programme, Task 22, Subtask A. The current test cases, E100-E200, represent the beginning of work on mechanical equipment test cases; additional cases that would expand the current test suite have been proposed for future development.
Neymark, J.; Judkoff, R.
US Department of Energys Regulatory Negotiations Convening on Commercial Certification for Heating, Ventilating, Air-Conditioning, and Refrigeration Equipment
US Department of Energy's Regulatory Negotiations Convening on US Department of Energy's Regulatory Negotiations Convening on Commercial Certification for Heating, Ventilating, Air-Conditioning, and Refrigeration Equipment Public Information for Convening Interviews I. What are the substantive issues DOE seeks to address? Strategies for grouping various basic models for purposes of certification; Identification of non-efficiency attributes, which do not impact the measured consumption of the equipment as tested by DOE's test procedure; The information that is certified to the Department; The timing of when the certification should be made relative to distribution in commerce; and Alterations to a basic model that would impact the certification.
Compressed air energy storage system
An internal combustion reciprocating engine is operable as a compressor during slack demand periods utilizing excess power from a power grid to charge air into an air storage reservoir and as an expander during peak demand periods to feed power into the power grid utilizing air obtained from the air storage reservoir together with combustible fuel. Preferably the internal combustion reciprocating engine is operated at high pressure and a low pressure turbine and compressor are also employed for air compression and power generation.
Ahrens, Frederick W. (Naperville, IL); Kartsounes, George T. (Naperville, IL)
Proposal for the award of a contract for the design, supply, installation and commissioning of a Heating, Ventilation and Air-Conditioning (HVAC) system for the computer room of the CERN Control Centre
Proposal for the award of a contract for the design, supply, installation and commissioning of a Heating Ventilation and Air Conditioning (HVAC) system for the HIE-ISOLDE infrastructure
The physical features of distribution of the small dispersive coal dust particles and the adsorbed radioactive chemical elements and their isotopes in the absorber with the granular filtering medium with the cylindrical coal granules were researched in the case of the intensive air dust aerosol stream flow through the iodine air filter (IAF). It was shown that, at the certain aerodynamic conditions in the IAF, the generation of the acoustic oscillations is possible. It was found that the acoustic oscillations generation results in an appearance of the standing acoustic waves of the air pressure (density) in the IAF. In the case of the intensive blow of the air dust aerosol, it was demonstrated that the standing acoustic waves have some strong influences on both: 1) the dynamics of small dispersive coal dust particles movement and their accumulation in the IAF; 2) the oversaturation of the cylindrical coal granules by the adsorbed radioactive chemical elements and their isotopes in the regions, where the antinodes of the acoustic waves are positioned. Finally, we completed the comparative analysis of the theoretical calculations with the experimental results, obtained for the cases of: 1) the experimental aerodynamic modeling of physical processes of the absorbed radioactive chemical elements and their isotopes distribution in the IAF; and 2) the gamma-activation spectroscopy analysis of the absorbed radioactive chemical elements and their isotopes distribution in the IAF. We made the innovative propositions on the necessary technical modifications with the purpose to improve the IAF technical characteristics and increase its operational time at the nuclear power plant (NPP), going from the completed precise characterization of the IAF parameters at the long term operation.
Oleg P. Ledenyov; Ivan M. Neklyudov
Experimental evaluation of oxygen-enriched air and emulsified fuels in a single-cylinder diesel engine. Volume 1, Concept evaluation
Compressed Air Energy Storage: Proven US CAES Plant Cost Achievements and Potential Engineering, Design & Project Management Based C ost Reductions
Compressed Air Energy Storage (CAES) is a market ready technology that can play a valuable role in enhancing grid flexibility for variable generation integration. Relative to combustion turbines, CAES provides additional benefits and value streams, such as potential classification as a transmission asset, lower emissions, superior regulation service, reduction of wind spillage and in other ways improving wind plant economics. Although high cost estimates for CAES circulate in the industry, the first ...
Model test on underground coal gasification (UCG) with low-pressure fire seepage push-through. Part I: Test conditions and air fire seepage
The technology of a pushing-through gallery with oxygen-enriched fire-seepage combustion was studied during shaft-free UCG in this article, and the main experiment parameters were probed. The test results were analyzed in depth. The patterns of variation and development were pointed out for the fire source moving speed, temperature field, leakage rate, the expanding diameter for the gasification gallery, and blasting pressure. Test results showed that, with the increase in the wind-blasting volume, the moving velocity for the fire source speeded up, and the average temperature for the gallery continuously rose. Under the condition of oxygen-enriched air blasting, when O{sub 2} contents stood at 90%, the moving speed for the fire source was 4-5 times that of air blasting. In the push-through process, the average leakage rate for the blasting was 82.23%, with the average discharge volume of 3.43 m{sup 3}/h and average gallery diameter of 7.87 cm. With the proceeding of firepower seepage, the extent of dropping for the leakage rate increased rapidly, and the drop rate for the blasting pressure gradually heightened.
Yang, L.H. [China University of Mining & Technology, Xuzhou (China)
On fuel selection in controlled auto-ignition engines : the link between intake conditions, chemical kinetics, and stratification
The objective of this research is to examine the impact fuel selection can have on the high-load limit in a stratified Compression Auto-Ignition (CAI) engine. This was accomplished by first studying the validity of the ...
Maria, Amir Gamal
Method and system for controlled combustion engines
A system for controlling combustion in internal combustion engines of both the Diesel or Otto type, which relies on establishing fluid dynamic conditions and structures wherein fuel and air are entrained, mixed and caused to be ignited in the interior of a multiplicity of eddies, and where these structures are caused to sequentially fill the headspace of the cylinders.
Oppenheim, A. K. (Berkeley, CA)
Conversion of a diesel engine to a spark ignition natural gas engine
Requirements for alternatives to diesel-fueled vehicles are developing, particularly in urban centers not in compliance with mandated air quality standards. An operator of fleets of diesel- powered vehicles may be forced to either purchase new vehicles or equip some of the existing fleets with engines designed or modified to run on alternative fuels. In converting existing vehicles, the operator can either replace the existing engine or modify it to burn an alternative fuel. Work described in this report addresses the problem of modifying an existing diesel engine to operate on natural gas. Tecogen has developed a technique for converting turbocharged automotive diesel engines to operate as dedicated spark-ignition engines with natural gas fuel. The engine cycle is converted to a more-complete-expansion cycle in which the expansion ratio of the original engine is unchanged while the effective compression ratio is lowered, so that engine detonation is avoided. The converted natural gas engine, with an expansion ratio higher than in conventional spark- ignition natural gas engines, offers thermal efficiency at wide-open- throttle conditions comparable to its diesel counterpart. This allows field conversion of existing engines. Low exhaust emissions can be achieved when the engine is operated with precise control of the fuel air mixture at stoichiometry with a 3-way catalyst. A Navistar DTA- 466 diesel engine with an expansion ratio of 16.5 to 1 was converted in this way, modifying the cam profiles, increasing the turbocharger boost pressure, incorporating an aftercooler if not already present, and adding a spark-ignition system, natural gas fuel management system, throttle body for load control, and an electronic engine control system. The proof-of-concept engine achieved a power level comparable to that of the diesel engine without detonation. A conversion system was developed for the Navistar DT 466 engine. NOx emissions of 1.5 g/bhp-h have been obtained.
Report on Preliminary Engineering Study for Installation of an Air Cooled Steam Condenser at Brawley Geothermal Plant, Unit No. 1
The Brawley Geothermal Project comprises a single 10 MW nominal geothermal steam turbine-generator unit which has been constructed and operated by the Southern California Edison Company (SCE). Geothermal steam for the unit is supplied through contract by Union Oil Company which requires the return of all condensate. Irrigation District (IID) purchases the electric power generated and provides irrigation water for cooling tower make-up to the plant for the first-five years of operation, commencing mid-1980. Because of the unavailability of irrigation water from IID in the future, SCE is investigating the application and installation of air cooled heat exchangers in conjunction with the existing wet (evaporative) cooling tower with make-up based on use of 180 gpm (nominal) of the geothermal condensate which may be made available by the steam supplier.
International Symposium on Air Breathing Engines, 9th, Athens, Greece, Sept. 3-8, 1989, Proceedings. Volumes 1 2
The conference presents papers on the National Aerospace Plane Program, highly loaded axial flow compressors, Swedish philosophy in aeroengine development, the active control of engine instabilities, and turbulent free shear layer mixing and combustion. Consideration is also given to direct and hybrid solutions of three-dimensional flow in axial radial turbomachines using the mean stream surface method, the numerical simulation of turbomachinery flows with a simple ONERA model of viscous effects, and the combustion characteristics of a boron-fueled SFRJ with aft burner. Other topics include studies on the influence of Mach number on profile losses of a reaction turbine cascade, flow in compressor interstage ducts, and full-scale liquid fuel ramjet combustor tests.
Engine lubrication oil aeration
The lubrication system of an internal combustion engine serves many purposes. It lubricates moving parts, cools the engine, removes impurities, supports loads, and minimizes friction. The entrapment of air in the lubricating ...
Baran, Bridget A. (Bridget Anne)
and basic components as refrigerators. Refrigerators use energy (usually electricity) to transfer heat from the cool interior of the refrigerator to the relatively warm...
Serial cooling of a combustor for a gas turbine engine
A combustor for a gas turbine engine uses compressed air to cool a combustor liner and uses at least a portion of the same compressed air for combustion air. A flow diverting mechanism regulates compressed air flow entering a combustion air plenum feeding combustion air to a plurality of fuel nozzles. The flow diverting mechanism adjusts combustion air according to engine loading.
Abreu, Mario E. (Poway, CA); Kielczyk, Janusz J. (Escondido, CA)
China Energy Efficiency Round Robin Testing Results for Room Air Conditioners
Refrigeration and Air Conditioning Industry Association Junein the context of the air conditioning industry, the profileand improvement of the air conditioning industry and the
Zhou, Nan
Indoor air movement acceptability and thermal comfort in hot-humid climates
Windsor Conference - Air Conditioning and the Low CarbonA. , Thomas, PC (2010). Air conditioning, comfort and energyAmerica's Romance with Air- Conditioning. Washington, D.C.
Candido, Christhina Maria
State of Washington Department of Health radioactive air emission notice of construction phase 1 for spent nuclear fuel project - hot conditioning system annex, project W-484
This notice of construction (NOC) provides information regarding the source and the estimated annual possession quantity resulting from the operation of the Hot Conditioning System Annex (HCSA). This information will be discussed again in the Phase II NOC, providing additional details on emissions generated by the operation of the HCSA. This Phase I NOC is defined as construct in the substructure, including but limited to, pouring the concrete for the floor; construction of the process pits and exterior walls; making necessary interface connections to the Canister Storage Building (CSB) ventilation and utility systems for personnel comfort; and extending the multi-canister over-pack (MCO) handling machine rails into the HCSA. A Phase II NOC will be submitted for approval prior to installation and is defined as the completion of the HCSA, which will consist of installation of Hot Conditioning System Equipment (HCSA), air emissions control equipment, and emission monitoring equipment. About 80 percent of the U.S. Department of Energy`s spent nuclear fuel (SNF) inventory is stored under water in the Hanford Site K Basins. Spent nuclear fuel in the K West Basin is contained in closed canisters, while the SNF in the K East Basin is contained in open canisters, which allow free release of corrosion products to the K East Basin water. Storage in the K Basins was originally intended to be on an as-needed basis to sustain operation of the N Reactor while the Plutonium-Uranium Extraction (PUREX) Plant was refurbished and restarted. The decision in December 1992 to deactivate the PUREX Plant left approximately 2,300 MT (2,530 tons) of N Reactor SNF in the K Basins with no means for near-term removal and processing. The HCSA will be constructed as an addition to the CSB and will contain the HCSA. The hot conditioning system (HCS) will remove chemically-bound water and will passivate the exposed uranium surfaces associated,with the SNF. The HCSA will house seven hot conditioning process stations, six operational and one auxiliary pit, which could be used as a welding area for final sealing of the vessel containing the SNF, or for neutron interrogation of the vessel containing the SNF to determine residual water content. Figures 1 and 2 contain map locations of the Hanford Site and the HCSA. `Response to Requirement` subtitle under each of the following sections identifies the corresponding Appendix A NOC application requirement listed under WAC 246-247-1 10.
Turnbaugh, J.E.
Results of 2001 Groundwater Sampling in Support of Conditional No Longer Contained-In Determination for the Snake River Plain Aquifer in the Vicinity of the Idaho Nuclear Technology and Engineering Center
This report summarizes the results of sampling five groundwater monitoring wells in the vicinity of the Idaho Nuclear Technology and Engineering Center at the Idaho National Engineering and Environmental Laboratory in 2001. Information on general sampling practices, quality assurance practices, parameter concentrations, representativeness of sampling results, and cumulative cancer risk are presented. The information is provided to support a conditional No Longer Contained-In Determination for the Snake River Plain Aquifer in the vicinity of the Idaho Nuclear Technology and Engineering Center.
Meachum, T.R.
Experimental and numerical study of the behavior of three-way catalytic converters under different engine operation conditions
The thesis reports the studies on how the three-way catalytic converters behave under different operation conditions. The main focus of the work is in the oxygen storage capacity of the three-way catalyst. Rich-to-lean ...
Zhang, Yuetao
Simulation model air-to-air plate heat exchanger
A simple simulation model of an air-to-air plate heat exchanger is presented. The model belongs to a collection of simulation models that allows the eflcient computer simulation of heating, ventilation, and air-conditioning (HVAC) systems. The main emphasis of the models is to shorten computation time and to use only input data that are known in the design process of an HVAC system. The target of the models is to describe the behavior of HVAC components in the part-load operation mode, which is becoming increasingly important in energy eficient HVAC systems. The models are intended to be used for yearly energy calculations or load calculations with time steps of about 10 minutes or larger. Short- time dynamic effects, which are of interest for different aspects of control theory, are neglected. The part-load behavior is expressed in terms of the nominal condition and the dimensionless variation of the heat transfer with change of mass flow and temperature. The effectiveness- NTU relations are used to parametrize the convective heat transfer at nominal conditions and to compute the part-load condition. If the heat transfer coefficients on the two exchanger sides are not equal (i. e. due to partial bypassing of air), their ratio can be easily calculated and set as a parameter. The model is static and uses explicit equations only. The explicit model formulation ensures short computation time and numerical stability, which allows using the model with sophisticated engineering methods like automatic system optimization. This paper fully outlines the algorithm description and its simplifications. It is not tailored for any particular simulation program to ensure easy implementation in any simulation program.
Truckstop Electrification Implementation Plan: A Diesel Engine Idle Reduction in Class 8 Trucks Using On-Vehicle Shore-Power Nationa l Demonstration Project
During any hour of the day in the United States, over 100,000 heavy-duty truck engines may be idling to provide heating or air conditioning for their resting drivers. During nighttime hours, this number might climb to 200,000 idling engines. Heating or air conditioning loads typically served by these idling engines only amount to one or two horsepower per truck. Because the parasitic loads required to keep these engines idling are typically from ten to thirty horsepower, exhaust emissions attributable to...
ground water source), electrically operated, unitary central air conditioners and central air conditioning heat pumps
Dehumidification and cooling loads from ventilation air
The importance of controlling humidity in buildings is cause for concern, in part, because of indoor air quality problems associated with excess moisture in air-conditioning systems. But more universally, the need for ventilation air has forced HVAC equipment (originally optimized for high efficiency in removing sensible heat loads) to remove high moisture loads. To assist cooling equipment and meet the challenge of larger ventilation loads, several technologies have succeeded in commercial buildings. Newer technologies such as subcool/reheat and heat pipe reheat show promise. These increase latent capacity of cooling-based systems by reducing their sensible capacity. Also, desiccant wheels have traditionally provided deeper-drying capacity by using thermal energy in place of electrical power to remove the latent load. Regardless of what mix of technologies is best for a particular application, there is a need for a more effective way of thinking about the cooling loads created by ventilation air. It is clear from the literature that all-too-frequently, HVAC systems do not perform well unless the ventilation air loads have been effectively addressed at the original design stage. This article proposes an engineering shorthand, an annual load index for ventilation air. This index will aid in the complex process of improving the ability of HVAC systems to deal efficiently with the amount of fresh air the industry has deemed useful for maintaining comfort in buildings. Examination of typical behavior of weather shows that latent loads usually exceed sensible loads in ventilation air by at least 3:1 and often as much as 8:1. A designer can use the engineering shorthand indexes presented to quickly assess the importance of this fact for a given system design. To size those components after they are selected, the designer can refer to Chapter 24 of the 1997 ASHRAE Handbook--Fundamentals, which includes separate values for peak moisture and peak temperature.
Harriman, L.G. III [Mason-Grant, Portsmouth, NH (United States); Plager, D. [Quantitative Decision Support, Portsmouth, NH (United States); Kosar, D. [Gas Research Inst., Chicago, IL (United States)
Optimal control of a bleed air temperature regulation system.
??This thesis investigates temperature control of an aircraft engine bleed air system, aiming at reducing ram air usage to reduce fuel consumption while maintaining fast� (more)
Shang, Lan
The Impact of GEM and MM5 Modeled Meteorological Conditions on CMAQ Air Quality Modeling Results in Eastern Canada and the Northeastern United States
The fifth-generation Pennsylvania State University�National Center for Atmospheric Research Mesoscale Model (MM5) is currently the meteorological model most widely used as input into the Community Multiscale Air Quality (CMAQ) modeling system. In ...
Steven C. Smyth; Dazhong Yin; Helmut Roth; Weimin Jiang; Michael D. Moran; Louis-Philippe Crevier
Combination of Local Wind Systems under Light Gradient Wind Conditions and Its Contribution to the Long-Range Transport of Air Pollutants
The meteorological structure and transport mechanism of long-range transport of air pollutants from the coastal region to the mountainous inland region were investigated using joint field observation data. The observations were conducted during ...
Hidemi Kurita; Hiromasa Ueda; Shigeki Mitsumoto
Department of Mechanical Engineering Spring 2012 HVAC Filter Sensor -Global
PENNSTATE Department of Mechanical Engineering Spring 2012 HVAC Filter Sensor - Global Overview The purpose of this project is to develop a heating, ventilation, and air conditioning (HVAC) monitoring a residential, forced flow, multi-zone HVAC filter needs to be replaced, and then alerts the users
Demirel, Melik C.
Air Conditioner "Evolves" in Novel NIST Study
... A new NIST tool combining principles of engineering with those of natural evolution yielded the design for a more energy-efficient roof-top air ...
Indoor Air Quality & Ventilation Group Staff Directory
Indoor Air Quality and Ventilation Group Staff. Staff Listing. Dr. Andrew K. Persily, Leader, Supervisory Mechanical Engineer, 301-975-6418. ...
Investigation of Feasibility of All-Fresh Air Supply in an All-Air System
The feasibility of an all-fresh air supply in an all-air system is investigated in theory, and the problem of AHU-handling air in low efficiency in summer and winter conditions is analyzed. The air supply temperature is almost up to standards when a heat recovery unit is fixed in the air conditioning system.
Wang, J.; Yan, Z.
Particulate Characteristics for Varying Engine Operation in a Gasoline Spark Ignited, Direct Injection Engine
The objective of this research is a detailed investigation of particulate sizing and number count from a direct-injection spark-ignited (DISI) engine at different operating conditions. The engine is a 549 [cc] single-cylinder, four valve engine with a flat-top piston, fueled by Tier II EEE. A baseline engine operating condition, with a low number of particulates, was established and repeatability at this condition was ascertained. This baseline condition is specified as 2000 rpm, 320 kPa IMEP, 280 [�bTDC] end of injection (EOI), and 25 [�bTDC] ignition timing. The particle size distributions were recorded for particle sizes between 7 and 289 [nm]. The baseline particle size distribution was relatively flat, around 1E6 [dN/dlogDp], for particle diameters between 7 and 100 [nm], before dropping off to decreasing numbers at larger diameters. Distributions resulting from a matrix of different engine conditions were recorded. These varied parameters include load, air-to-fuel ratio (A/F), spark timing, injection timing, fuel rail pressure, and oil and coolant temperatures. Most conditions resulted with uni-modal type distributions usually with an increase in magnitude of particles in comparison to the baseline, with the exception of lean operation with retarded ignition timing. Further investigation revealed high sensitivity of the particle number and size distribution to changes in the engine control parameters. There was also a high sensitivity of the particle size distributions to small variations in A/F, ignition timing, and EOI. Investigations revealed the possibility of emissions oxidation in the exhaust and engine combustion instability at later EOI timings which therefore ruled out late EOI as the benchmark condition. Attempts to develop this benchmark revealed engine sensitivity to A/F and ignition timing, especially at later EOI operation
Farron, Carrie; Matthias, Nick; Foster, David E.; Andrie, Mike; Krieger, Roger; Najt, Paul; Narayanaswamy, Kushal; Solomon, Arun; Zelenyuk, Alla
SolarAire LLC | Open Energy Information
SolarAire LLC Place Folsom, California Sector Solar Product Developing a solar thermal air conditioning unit. References SolarAire LLC1 LinkedIn Connections CrunchBase Profile...
Single-Duct Constant Air Volume System Supply Air Temperature Reset: Using Return Air Temperature or Outside Air Temperature?
The supply air temperature set point for a singleduct constant air volume air handling unit (AHU) system is often reset based on either return air temperature or outside air temperature in order to reduce simultaneous cooling and heating energy consumption. Both reset strategies make engineering sense as long as the reset schedules are reasonable. Quite often the decision to use one over the other is made with the assumption that they will all achieve some sorts of energy savings. However, the impact of these two strategies on AHU energy consumption could be very different. A comparison of these two commonly used supply air temperature reset strategies for a single-duct constant air volume system is presented in this paper. It is shown that from either the building energy consumption or building comfort point of view, the reset strategy based on outside air temperature is inherently better than that based on return air temperature. Significant amount of heating energy savings can be achieved by switching from return air temperature based reset to outside air temperature based reset. The reset strategy can also benefit variable air volume (VAV) AHUs. An improved supply air temperature set point reset control strategy is proposed by combining and staging the outside air and return air temperature based resets.
Wei, G.; Turner, W. D.; Claridge, D.; Liu, M.
A preliminary design study of the nuclear gas engine, consisting of a gas-cooled reactor directly coupled to a reciprocating engine, is presented. The principles of operation of the proposed gas engine are outlined and typical variations anre discussed. The nuclear gas engine is compared with other reciprocating engines and air compressors. A comparison between the ideal and actual cycles is made, with particular attention given to pumping, heat, and other losses to be expected. The applications and development of the nuclear gas engine are discussed. (W.D.M.)
Fraas, A.P.
The Phillips Stirling engine
This book is about the Stirling engine and its development from the heavy cast-iron machine of the 19th century to that of today. It is a history of a research effort spanning nearly 50 years, together with an outline of principles, and some technical details and descriptions of the more important engines. Contents include: the hot-air engine; the 20th-century revival; the Stirling cycle; rhombic-drive engines; heating and cooling; pistons and seals; electric generators and heat pumps; exotic heat sources; the engine and the environment; swashplate engines; and the past and the future.
Hargreaves, C.M.
High-Compression-Ratio; Atkinson-Cycle Engine Using Low-Pressure Direct Injection and Pneumatic-Electronic Valve Actuation Enabled by Ionization Current and Foward-Backward Mass Air Flow Sensor Feedback
This report describes the work completed over a two and one half year effort sponsored by the US Department of Energy. The goal was to demonstrate the technology needed to produce a highly efficient engine enabled by several technologies which were to be developed in the course of the work. The technologies included: (1) A low-pressure direct injection system; (2) A mass air flow sensor which would measure the net airflow into the engine on a per cycle basis; (3) A feedback control system enabled by measuring ionization current signals from the spark plug gap; and (4) An infinitely variable cam actuation system based on a pneumatic-hydraulic valve actuation These developments were supplemented by the use of advanced large eddy simulations as well as evaluations of fuel air mixing using the KIVA and WAVE models. The simulations were accompanied by experimental verification when possible. In this effort a solid base has been established for continued development of the advanced engine concepts originally proposed. Due to problems with the valve actuation system a complete demonstration of the engine concept originally proposed was not possible. Some of the highlights that were accomplished during this effort are: (1) A forward-backward mass air flow sensor has been developed and a patent application for the device has been submitted. We are optimistic that this technology will have a particular application in variable valve timing direct injection systems for IC engines. (2) The biggest effort on this project has involved the development of the pneumatic-hydraulic valve actuation system. This system was originally purchased from Cargine, a Swedish supplier and is in the development stage. To date we have not been able to use the actuators to control the exhaust valves, although the actuators have been successfully employed to control the intake valves. The reason for this is the additional complication associated with variable back pressure on the exhaust valves when they are opened. As a result of this effort, we have devised a new design and have filed for a patent on a method of control which is believed to overcome this problem. The engine we have been working with originally had a single camshaft which controlled both the intake and exhaust valves. Single cycle lift and timing control was demonstrated with this system. (3) Large eddy simulations and KIVA based simulations were used in conjunction with flow visualizations in an optical engine to study fuel air mixing. During this effort we have devised a metric for quantifying fuel distribution and it is described in several of our papers. (4) A control system has been developed to enable us to test the benefits of the various technologies. This system used is based on Opal-RT hardware and is being used in a current DOE sponsored program.
Harold Schock; Farhad Jaberi; Ahmed Naguib; Guoming Zhu; David Hung
Air Handling Unit Supply Air Temperature Optimization During Economizer Cycles
Most air handling units (AHUs) in commercial buildings have an air economizer cycle for free cooling under certain outside air conditions. During the economizer cycle, the outside air and return air dampers are modulated to seek mixing air temperature at supply air temperature setpoint. Mechanical cooling is always required when outside air temperature is higher than the supply air temperature setpoint. Generally the supply air temperature setpoint is set at 55�F for space humidity control. Actually the dehumidification is not necessary when outside air dew point is less than 55�F. Meanwhile the space may have less cooling load due to envelope heat loss and/or occupant schedule. These provide an opportunity to use higher supply air temperature to reduce or eliminate mechanical cooling and terminal box reheat. On the other hand the higher supply air temperature will require higher air flow as well as higher fan power. Therefore the supply air temperature has to be optimized to minimize the combined energy for fan, cooling and heating energy. In this paper a simple energy consumption model is established for AHU systems during the economizer and then a optimal supply air temperature control is developed to minimize the total cost of the mechanical cooling and the fan motor power. This paper presents AHU system energy modeling, supply air temperature optimization, and simulated energy savings.
Xu, K.; Liu, M.; Wang, G.; Wang, Z.
Common Air Conditioner Problems | Department of Energy
Common Air Conditioner Problems Common Air Conditioner Problems Common Air Conditioner Problems May 30, 2012 - 6:41pm Addthis A refrigerant leak is one common air conditioning problem. | Photo courtesy of ©iStockphoto/BanksPhotos. A refrigerant leak is one common air conditioning problem. | Photo courtesy of ©iStockphoto/BanksPhotos. What does this mean for me? You can eliminate the most common air conditioner problems before hiring an air conditioning technician. You can do some air conditioner maintenance and repair tasks yourself. One of the most common air conditioning problems is improper operation. If your air conditioner is on, be sure to close your home's windows and outside doors. For room air conditioners, isolate the room or a group of connected rooms as much as possible from the rest of your home.
Air-Con International: Noncompliance Determination and Proposed...
to Air-Con International finding that a variety of central air conditioners and air conditioning heat pumps distributed under the Air-Con private label do not comport...
The Impact of Climate Change on Air Quality�Related Meteorological Conditions in California. Part II: Present versus Future Time Simulation Analysis
In this study, the Weather Research and Forecasting (WRF) model was applied to dynamically downscale the Parallel Climate Model (PCM) projection for the climate change impact on regional meteorological conditions in California. Comparisons were ...
Zhan Zhao; Shu-Hua Chen; Michael J. Kleeman; Abdullah Mahmud
The Impact of Climate Change on Air Quality Related Meteorological Conditions in California � Part II: Present versus Future Time Simulation Analysis
In this study, the Weather Research and Forecasting (WRF) model was applied to dynamically downscale the Parallel Climate Model (PCM) projection for the climate change impact on regional meteorological conditions in California (CA). Comparisons ...
Numerical Analysis of a Cold Air Distribution System
Cold air distribution systems may reduce the operating energy consumption of air-conditioned air supply system and improve the outside air volume percentages and indoor air quality. However, indoor temperature patterns and velocity field are easily non-uniform so that residents usually feel uncomfortable. The distribution of indoor airflow by cold air distribution is researched in this paper. We study indoor air distribution under different low temperature air supply conditions by numerical simulation. The simulated results agree well with the experiments.
Zhu, L.; Li, R.; Yuan, D.
U.S. Environmental Protection Agency Clean Air Act notice of construction for spent nuclear fuel project - hot conditioning system annex, project W-484
This notice of construction (NOC) provides information regarding the source and the estimated quantity of potential airborne radionuclide emissions resulting from the operation of the Hot Conditioning System (HCS) Annex. The construction of the HCS Annex is scheduled to conunence on or about December 1996, and will be completed when the process equipment begins operations. This document serves as a NOC pursuant to the requirements of 40 Code of Federal Regulations (CFR) 61 for the HCS Annex. About 80 percent of the U.S. Department of Energy`s spent nuclear fuel (SNF) inventory is stored under water in the Hanford Site K Basins. Spent nuclear fuel in the K West Basin is contained in closed canisters, while the SNF in the K East Basin is contained in open canisters, which allows release of corrosion products to the K East Basin water. Storage of the current inventory in the K Basins was originally intended to be on an as-needed basis to sustain operation of the N Reactor while the Plutonium-Uranium Extraction (PUREX) Plant was refurbished and restarted. The decision in December 1992 to deactivate the PUREX Plant left approximately 2, 1 00 MT (2,300 tons) of uranium, as part of 1133 N Reactor SNF in the K Basins with no means for near-term removal and processing. The HCS Annex will be constructed as an annex to the Canister Storage Building (CSB) and will contain the hot conditioning equipment. The hot conditioning system (HCS) will release chemically-bound water and will condition (process of using a controlled amount of oxygen to destroy uranium hydride) the exposed uranium surfaces associated with the SNF through oxidation. The HCS Annex will house seven hot conditioning process stations, six operational and one auxiliary, which could be used as a welding area for final closure of the vessel containing the SNF. The auxiliary pit is being evaluated at this time for its usefulness to support other operations that may be needed to ensure proper conditioning of the SNF and proper storage of the vessel containing the SNF. Figures I and 2 contain map locations of the Hanford Site and the HCS Annex.
Baker, S.K., Westinghouse Hanford
Room Air Conditioners | Department of Energy
Room Air Conditioners Room Air Conditioners Room Air Conditioners July 1, 2012 - 5:35pm Addthis A window air conditioner is one solution to cooling part of a house. | Photo courtesy of ©iStockphoto/kschulze. A window air conditioner is one solution to cooling part of a house. | Photo courtesy of ©iStockphoto/kschulze. What does this mean for me? Room air conditioners are less expensive and disruptive to install than central air conditioning systems. Room air conditioners can be a cost-effective alternative to central air conditioning systems. How does it work? Room air conditioners work by cooling one part of your home. Room or window air conditioners cool rooms rather than the entire home or business. If they provide cooling only where they're needed, room air conditioners are less expensive to operate than central units, even though
Air Quality
What We Monitor & Why » What We Monitor & Why » Air Quality Air Quality To preserve our existing wilderness-area air quality, LANL implements a conscientious program of air monitoring. April 12, 2012 Real-time data monitoring for particulate matter An air monitoring field team member tests one of LANL's tapered element oscillating microbalance samplers, which collects real-time particulate matter data. Contact Environmental Communication & Public Involvement P.O. Box 1663 MS M996 Los Alamos, NM 87545 (505) 667-0216 Email LANL monitors air quality 24 hours a day, 365 days a year. Why we monitor air LANL monitors many different pathways in order to assess their impact on workers, the public, animals, and plants. We monitor the air around the Laboratory to ensure our operations are not affecting the air of nearby
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Energy Consumption Estimation for Room Air-conditioners Using Room Temperature Simulation with One-Minute Intervals
For the purpose of developing optimized control algorithm for room air-conditioners to ensure their energy efficiency, a short time interval (i.e., one minute) simulation of building thermal performance is necessary because the sampling time interval for room air-conditioner control is one minute in general. This paper studies the short-time interval room air temperature simulation method using the response factor method. Using the simulated room air temperature, an air-conditioner's running time can be known so that its energy consumption can be estimated accurately. In order to verify the simulation accuracy, an actual room equipped with a gas-engine heat pump (GHP) air-conditioning system is studied by both simulation and measurement. The cooling amount produced by the GHP is calculated using measured refrigerant pressure and temperature at condenser and evaporator respectively. The Root Mean Square Error (RMSE) between measured cooling amount and simulated cooling load is 18.9 percent of the average measured value. The profile of simulated room air temperature in both air-conditioned daytime and nighttime without air-conditioning can match the measured room air temperature. With respect to the estimated energy consumption, the profile of simulated energy consumption can match the measured data. The simulation accuracy of room air temperature and energy consumption during the air-conditioner start-up period is not good and needs to be improved in future research. But in general, the verification shows that this energy consumption simulation method is acceptable for evaluating the energy performance of a room air-conditioner, and can also be a useful tool for commissioning room air-conditioners.
Wang, F.; Yoshida, H.; Matsumoto, K.
Air flow and pressure inside a pressure-swirl spray and their effects on spray development
Air flow and pressure inside a pressure-swirl spray for direct injection (DI) gasoline engines and their effects on spray development have been analyzed at different injector operating conditions. A simulation tool was utilized and the static air pressure at the centerline of the spray was measured to investigate the static pressure and flow structure inside the swirl spray. To investigate the effect of static air pressure on swirl spray development, a liquid film model was applied and the Mie-scattered images were captured. The simulation and experiment showed that recirculation vortex and air pressure drop inside the swirl spray were observable and the air pressure drop was greater at high injection pressure. At high fuel temperature, the air pressure at the nozzle exit showed higher value compared to the atmospheric pressure and then continuously decreased up to few millimeters distance from the nozzle exit. The pressure drop at high fuel temperatures was more than that of atmospheric temperature. This reduced air pressure was recovered to the atmospheric pressure at further downstream. The results from the liquid film model and macroscopic spray images showed that the air pressure started to affect the liquid film trajectory about 3 mm from the nozzle exit and this effect was sustained until the air pressure recovered to the atmospheric pressure. However, the entrained air motion and droplet size have more significant influence on the spray development after the most of the liquid sheet is broken-up and the spray loses its initial momentum. (author)
Moon, Seoksu; Bae, Choongsik [Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, Guseong-dong, Yuseong-gu, Daejon 305-701 (Korea); Abo-Serie, Essam [Department of Mechanical Engineering and Design, Coventry University, Priory Street, Coventry CV1 5FB (United Kingdom)
Cromer Cycle Air Conditioner: A Unique Air-Conditioner Desiccant Cycle to Enhance Dehumidification and Save Energy
The Cromer cycle uses a desiccant to move moisture from the saturated air leaving an air conditioning (AC) cooling coil to the air returning to the AC unit from the conditioned space. This has the thermodynamic effect of reducing the overall energy consumption of the AC unit and also has the side benefit of dramatically increasing the moisture removal capacity of the AC coil. Simulations, engineering analysis and laboratory tests have confirmed the technical feasibility of the thermodynamics of the cycle. This work reports on a test at ARI conditions (95 deg. F outside, 80 deg F, 51% RH inside). The test unit (10 year old, 5 ton Bryant Air Conditioner) without the Cromer cycle, averaged an EER of 7.93 at a latent ratio of 26.2 % (SHR = 0.738). With the Cromer cycle added, the same unit averaged a total cooling EER of 11.82 with a water removal latent ratio of 53.4% (SHR= 0.466). The measured 16.4% reduction in energy use and 47.9 improvement in EER is significant for the tests at the 95% confidence level. This technology represents a major improvement in energy performance for the control of humidity conditions.
Cromer, C. J.
SOLERAS - Solar Cooling Engineering Field Tests Project: Arizona State University. Prototype carrier 10 ton air-cooled solar absorption chiller. Final evaluation report
A prototype air-cooled 10 ton solar absorption chiller was disassembled and inspected after having been field-tested for three consecutive cooling seasons. Included in the inspection were some flow visualization experiments which revealed some problems in the absorber header design. The objectives of this evaluation project were to determine possible causes for the frequent crystallization and generally below-design performance of the chiller during the testing period. The major conclusions reached were that a combination of leaks and of poor (50%) flow distribution in the absorber could account for most of the chiller's poor performance.
International Energy Agency Building Energy Simulation Test and Diagnostic Method for Heating, Ventilating, and Air-Conditioning Equipment Models (HVAC BESTEST): Volume 2: Cases E300-E545.
This report documents an additional set of mechanical system test cases that are planned for inclusion in ANSI/ASHRAE STANDARD 140. The cases test a program's modeling capabilities on the working-fluid side of the coil, but in an hourly dynamic context over an expanded range of performance conditions. These cases help to scale the significance of disagreements that are less obvious in the steady-state cases. The report is Vol. 2 of HVAC BESTEST Volume 1. Volume 1 was limited to steady-state test cases that could be solved with analytical solutions. Volume 2 includes hourly dynamic effects, and other cases that cannot be solved analytically. NREL conducted this work in collaboration with the Tool Evaluation and Improvement Experts Group under the International Energy Agency (IEA) Solar Heating and Cooling Programme Task 22.
Neymark J.; Judkoff, R.
Components for Advanced Power Conditioning Techniques
Symposium, Advanced Materials for Power Electronics, Power Conditioning, and Power Conversion ... Potential Ceramic Dielectrics for Air Force Applications.
Integrating ducts into the conditioned space: Successes and challenges
air into the conditioned space. Further conversations with construction crews indicated that sealing
Siegel, Jeffrey; Walker, Iain
Issue and Improvement Measure of Multi-split Air Conditioner
Existing problems of traditional air source variable refrigerant flow (VRF) air-conditioning system are analyzed. The disadvantages of traditional VRF air-conditioning system are described in detail: 1) its properties are seriously affected by outdoor ... Keywords: energy saving, simulation, variable refrigerant flow air conditioning, water loop
Sun Tingting; Ni Long; Yao Yang; Ma Zuiliang; Yi Lingli
Residential Forced Air System Cabinet Leakage and Blower Performance
CA. � CEC�(2008b). �Residential�Alternative�Calculation�Standard�for�Air�Handlers�in�Residential�Space�Conditioning�of�Standards�Options�for�Residential�Air�Handler�Fans. ��
Walker, Iain S.
The Use of Positive Matrix Factorization with Conditional Probability Functions in Air Quality Studies: An Application to Hydrocarbon Emissions in Houston, Texas
As part of a study to identify groups of compounds (�source categories�) associated with different processing facilities, a multivariate receptor model called Positive Matrix Factorization (PMF) was applied to hourly average concentrations of volatile organic compounds (VOCs) measured at five Photochemical Assessment Monitoring Stations (PAMS) located near the Ship Channel in Houston, Texas. The observations were made between June and October, 2003, and limited to nighttime measurements (21:00 pm � 6:00 am) in order to remove the complexity of photochemical processing and associated changes in the concentrations of primary and secondary VOCs. Six to eight volatile organic compounds source categories were identified for the five Ship Channel sites. The dominant source categories were found to be those associated with petrochemical, chemical industries and fuel evaporation. In contrast, source categories associated with on-road vehicles were found to be relatively insignificant. Although evidence of biogenic emissions was found at almost all the sites, this broad category was significant only at the Wallisville site, which was also the site furthest away from the Ship Channels area and closest to the northeast forest of Texas. Natural gas, accumulation and fuel evaporation sources were found to contribute most to the ambient VOCs, followed by the petrochemical emission of highly reactive ethene and propylene. Solvent / paint industry and fuel evaporation and emission from refineries were next in importance while the on-road vehicle exhaust generally contributed less than 10% of the total ambient VOCs. Specific geographic areas associated with each source category were identified through the use of a Conditional Probability Function (CPF) analysis that related elevated concentrations of key VOCs in each category to a network of grids superimposed on the source inventories of the VOCs.
Xie, YuLong; Berkowitz, Carl M.
Heavy-Duty Stoichiometric Compression Ignition Engine with Improved Fuel Economy over Alternative Technologies for Meeting 2010 On-Highway Emission
The objectives of the reported work were: to apply the stoichiometric compression ignition (SCI) concept to a 9.0 liter diesel engine; to obtain engine-out NO{sub x} and PM exhaust emissions so that the engine can meet 2010 on-highway emission standards by applying a three-way catalyst for NO{sub x} control and a particulate filter for PM control; and to simulate an optimize the engine and air system to approach 50% thermal efficiency using variable valve actuation and electric turbo compounding. The work demonstrated that an advanced diesel engine can be operated at stoichiometric conditions with reasonable particulate and NOx emissions at full power and peak torque conditions; calculated that the SCI engine will operate at 42% brake thermal efficiency without advanced hardware, turbocompounding, or waste heat recovery; and determined that EGR is not necessary for this advanced concept engine, and this greatly simplifies the concept.
Kirby J. Baumgard; Richard E. Winsor
Scenes from Argonne's Materials Engineering Research Facility...
Share Description B-roll for the Materials Engineering Research Facility Topic Energy Energy usage Energy storage Batteries Lithium-air batteries Lithium-ion batteries Programs...
Internal combustion engine
An improvement to an internal combustion engine is disclosed that has a fuel system for feeding a fuel-air mixture to the combustion chambers and an electrical generation system, such as an alternator. An electrolytic cell is attached adjacent to the engine to generate hydrogen and oxygen upon the application of a voltage between the cathode and anode of the electrolytic cell. The gas feed connects the electrolytic cell to the engine fuel system for feeding the hydrogen and oxygen to the engine combustion chambers. Improvements include placing the electrolytic cell under a predetermined pressure to prevent the electrolyte from boiling off, a cooling system for the electrolytic cell and safety features.
Valdespino, J.M.
Effects of Gasoline Direct Injection Engine Operating Parameters on Particle Number Emissions
A single-cylinder, wall-guided, spark ignition direct injection engine was used to study the impact of engine operating parameters on engine-out particle number (PN) emissions. Experiments were conducted with certification gasoline and a splash blend of 20% fuel grade ethanol in gasoline (E20), at four steady-state engine operating conditions. Independent engine control parameter sweeps were conducted including start of injection, injection pressure, spark timing, exhaust cam phasing, intake cam phasing, and air-fuel ratio. The results show that fuel injection timing is the dominant factor impacting PN emissions from this wall-guided gasoline direct injection engine. The major factor causing high PN emissions is fuel liquid impingement on the piston bowl. By avoiding fuel impingement, more than an order of magnitude reduction in PN emission was observed. Increasing fuel injection pressure reduces PN emissions because of smaller fuel droplet size and faster fuel-air mixing. PN emissions are insensitive to cam phasing and spark timing, especially at high engine load. Cold engine conditions produce higher PN emissions than hot engine conditions due to slower fuel vaporization and thus less fuel-air homogeneity during the combustion process. E20 produces lower PN emissions at low and medium loads if fuel liquid impingement on piston bowl is avoided. At high load or if there is fuel liquid impingement on piston bowl and/or cylinder wall, E20 tends to produce higher PN emissions. This is probably a function of the higher heat of vaporization of ethanol, which slows the vaporization of other fuel components from surfaces and may create local fuel-rich combustion or even pool-fires.
He, X.; Ratcliff, M. A.; Zigler, B. T.
Operation of an aircraft engine using liquefied methane fuel
The operation of a reciprocating aircraft engine on methane fuel is demonstrated. Since storage of the methane fuel in the gaseous state would impractical for a flight fuel system, a liquid storage system was used. System valving was configured to deliver only liquid methane to the engine supply line. The equipment description includes photo and diagram illustrations of the liquid methane storage dewar, and photos of the methane heat exchanger, pressure regulator and air-fuel mixer. The engine test results are presented for gasoline and methane in terms of RPM, horsepower, fuel flow, specific energy consumption and standard conditions horsepower. Conclusions include the finding that conversion of an aircraft reciprocating engine to operate on liquified methane is possible with very satisfactory results.
Raymer, J.A.
Free-piston engine
A combustion system which can utilize high compression ratios, short burn durations, and homogeneous fuel/air mixtures in conjunction with low equivalence ratios. In particular, a free-piston, two-stroke autoignition internal combustion engine including an electrical generator having a linear alternator with a double-ended free piston that oscillates inside a closed cylinder is provided. Fuel and air are introduced in a two-stroke cycle fashion on each end, where the cylinder charge is compressed to the point of autoignition without spark plugs. The piston is driven in an oscillating motion as combustion occurs successively on each end. This leads to rapid combustion at almost constant volume for any fuel/air equivalence ratio mixture at very high compression ratios. The engine is characterized by high thermal efficiency and low NO.sub.x emissions. The engine is particularly suited for generating electrical current in a hybrid automobile.
Van Blarigan, Peter (Truckee, CA)
Modeling the effects of late cycle oxygen enrichment on diesel engine combustion and emissions.
A multidimensional simulation of Auxiliary Gas Injection (AGI) for late cycle oxygen enrichment was exercised to assess the merits of AGI for reducing the emissions of soot from heavy duty diesel engines while not adversely affecting the NO{sub x} emissions of the engine. Here, AGI is the controlled enhancement of mixing within the diesel engine combustion chamber by high speed jets of air or another gas. The engine simulated was a Caterpillar 3401 engine. For a particular operating condition of this engine, the simulated soot emissions of the engine were reduced by 80% while not significantly affecting the engine-out NO{sub x} emissions compared to the engine operating without AGI. The effects of AGI duration, timing, and orientation are studied to confirm the window of opportunity for realizing lower engine-out soot while not increasing engine out NO{sub x} through controlled enhancement of in-cylinder mixing. These studies have shown that this window occurs during the late combustion cycle, from 20 to 60 crank angle degrees after top-dead-center. During this time, the combustion chamber temperatures are sufficiently high that soot oxidation increases in response in increased mixing, but the temperature is low enough that NO{sub x} reactions are quenched. The effect of the oxygen composition of the injected air is studied for the range of compositions between 21% and 30% oxygen by volume. This is the range of oxygen enrichment that is practical to produce from an air separation membrane. Simulations showed that this level of oxygen enrichment is insufficient to provide an additional benefit by either increasing the level of soot oxidation or prolonging the window of opportunity for increasing soot oxidation through enhanced mixing.
Mather, D. K.; Foster, D. E.; Poola, R. B.; Longman, D. E.; Chanda, A.; Vachon, T. J.
Engines - Spark Ignition Engines
Spark Ignition Engines Spark Ignition Engines Thomas Wallner and omni engine Thomas Wallner and the omnivorous engine Background Today the United States import more than 60% of its crude oil and petroleum products. Transportation accounts for a major portion of these imports. Research in this field is focused on reducing the dependency on foreign oil by increasing the engine efficiency on the one hand and blending gasoline with renewable domestic fuels, such as ethanol, on the other. Argonne's Research The main focus of research is on evaluation of advanced combustion concepts and effects of fuel properties on engine efficiency, performance and emissions. The platforms used are a single-cylinder research engine as well as an automotive-size four-cylinder engine with direct fuel injection.
Powdered coal air dispersion nozzle
An improved coal/air dispersion nozzle introduces fuel into the combustion chamber of a gas turbine engine as a finely atomized, dispersed spray for a uniform combustion. The nozzle has an inlet that receives finely powdered coal from a coal transport or coal/air fluidizer system and a scroll swirl generator is included within the nozzle to swirl a fluidized coal/air mixture supplied to the inlet of the nozzle. The scroll is in the form of a thin, flat metal sheet insert, twisted along its length, and configured to prevent build-up of coal particles within the nozzle prior to ejection from its outlet. Airblast air jets are included along the length of the nozzle body to assist in the discharge of the fluidized coal from the nozzle outlet and an angular pintle tip overlies the outlet to redirect coal/air mixture through a desired fluidized coal spray angle.
Kosek, T.P.; Steinhilper, E.A.
Variables optimization of building air conditioning system
A heating and climatizer system based on selective absorption of solar energy by a selective collector. The experimental study shows that the performance of this system depends on several variables: the nature of the colporteur fluid, the flow of the ... Keywords: heating and climatisation, modelation and optimization, solar energy
Marius-Constantin Popescu; Cornelia Aida Bulucea; Gheorghe Manolea; Cristian Vladu
Presentation of the Air- Conditioning, Heating, and ...
... GCC Standardization Organization (GSO) on the ... Headquarters: Arlington, Virginia USA Page 4. AHRI � ... Directory ? www.ahridirectory.org Page 18. ...
Injection engine as a control object. II. Problems of automatic control of the engine
Specific features of injection engine as a control object are discussed, strict formulations of problems of engine automatic control and principles of their solution are presented. Examples of solution of the problem of stabilization of air-fuel ratio ...
D. N. Gerasimov; H. Javaherian; D. V. Efimov; V. O. Nikiforov
Optimal Outside Air Control for Air Handling Units with Humidity Control
Most air handling units (AHUs) in commercial buildings have the (air) economizer cycle to use outside air for free cooling under certain outside air conditions. Ideally the economizer cycle is enabled if outside air enthalpy is less than return air enthalpy. During the economizer cycle, outside air flow is modulated to seek mixed air temperature at a supply air temperature set point. Since the outside air may be dry during the economizer cycle, humidification is required for AHUs with humidity control. As a result, the economizer cycle saves cooling energy but requires excessive steam for humidification. Therefore the economizer cycle may not be economical. An optimal outside air control method is developed to minimize the total cost of mechanical cooling and steam humidification. The impacts of chilled water price, steam price, and space minimum humidity set point are analyzed. Finally the optimal outside air control zones are presented on a psychrometric chart under differential energy price ratios and minimum indoor humidity set points.
Wang, G.; Liu, M.
Performance of an air-cooled ammonia-water absorption air conditioner at low generator temperatures
An ammonia--water absorption air conditioning system has been tested to investigate the stability of operation near the cut-off conditions. Circulation ratios were from 8 to 30. Relations for the estimation of the coefficient of performance and for the prediction of operating temperatures were derived and verified experimentally. Possible operating conditions for an air-cooled ammonia--water air conditioning system were concluded.
Dao, K.; Simmons, M.; Wolgast, R.; Wahlig, M.
NREL: Photovoltaics Research - Engineering
Photovoltaic Engineering Photovoltaic Engineering Photovoltaic (PV) Engineering at NREL supports commercial and emerging PV technology development. Our support covers the following three areas: Engineering Testing and Evaluation. We provide engineering testing and evaluation of PV products developed by companies during work sponsored by the U.S. Department of Energy (DOE). We determine if products meet performance criteria established by DOE for a company's contractual obligations. Standards Development. We support the development of national and international standards. Current work includes investigating methods of preconditioning cadmium telluride and copper indium gallium diselenide PV modules so that when they are tested for reporting conditions, the results are correlated