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Proposed Haymarket District Heating and Cooling System, Lincoln, Nebraska: Phase 1, Feasibility Report.
National Technical Information Service (NTIS)
This study attempts to examine the prospects of serving a 16 block downtown area with a new district heating and cooling system. The system would deliver hot water and chilled water to the various buildings in the district who choose to be connected. The ...
Assessment of impact of advanced energy transmission fluids on district heating and cooling systems (Phase 1)
SciTech Connect
Argonne National Laboratory (ANL), under sponsorship of the US Department of Energy (DOE) Office of Buildings and Community Systems, has embarked upon a comprehensive, long-range program to develop high-performance advanced energy transmission fluids for use in district heating and cooling (DHC) systems. ANL has the lead technical role in this DOE program. These advanced fluids will substantially reduce flow frictional losses and enhance energy transfer. In system enhancement scoping studies conducted by ANL, the fluids yielded potentially significant upfront capital equipment cost reductions by allowing the use of smaller pipes, pumps, heat exchangers, and storage tanks as well as reductions in operational costs. This report presents the first-phase results of assessment of impact of the advanced fluids on DHC systems. Future reports will focus on assessment of impact on hardware performance, capital eqiupment, and operation costs. 9 refs., 30 figs., 2 tab.
Kasza, K.E.; Chen, M.M.
District heating\\/cooling potential in New York City. phase 1. Final report
Microsoft Academic Search
New York City through its Energy Office has identified and evaluated the technical and economic feasibility of district heating and cooling at three locations: Brooklyn Navy Yard, Kings County Medical Complex, and the S.W. Brooklyn Incinerator. Of these the Navy Yard has the most immediate potential for implementation. The Navy Yard has an extensive steam and electrical system that has
G. T. McLoughlin; R. P. Kuo; J. Karol
District heating and cooling market assessment
For more than 10 years, the U.S. Department of Energy (DOE) has supported research on and development of district steam, hot-water, and chilled-water systems in the residential and commercial sectors. In 1991, DOE sponsored a research project at Argonne National Laboratory (ANL) to reestimate the national market for district heating and cooling (DHC) systems to the year 2010. ANL had previously developed a DHC market-penetration model and used it to project future market penetration. The first step in the project was to conduct a literature search to identify major data sources on historical DHC markets and any past studies on the future market potential of DHC systems. On the basis of an evaluation of the available data and methodologies for estimating market penetration of new technologies, it was concluded that ANL should develop a new econometric model for forecasting DHC markets. By using the 1989 DOE/Energy Information Administration Commercial Buildings Energy Consumption Surveys (CBECS) public-use-tape data, a model was estimated for steam, hot-water, and chilled-water demand in the buildings surveyed. The model provides estimates of building steam, hot-water, and chilled-water consumption and expenditures between now and the year 2010. The analysis shows that the total U.S. market for district steam, hot water, and chilled water could grow from 0.8 quadrillion British thermal units (quad) in 1989 to 1.0 quad by 2000 and 1.25 quad by 2010. The demand for chilled water could nearly double in the forecast period, and its share could approach one-third of the total DHC market. This model, and the results, should be of use to policymakers, researchers, and market participants involved in the planning and implementation of community-based, energy-conserving, and environmentally beneficial energy systems.
Teotia, A.P.S.; Karvelas, D.E.; Daniels, E.J.; Anderson, J.L.
District Heating and Cooling in the United States: Prospects and Issues.
A National Research Council (NRC) Committee on District Heating and Cooling in its report, 'District Heating and Cooling in the United States: Prospects and Issues', concludes that district heating and cooling could help reduce the nation's dependence on ...
Impact of advanced fluids on costs of district cooling systems
Three alternate fluids, ice-water slurry, friction reduction additive and the combination of them, have been compared for use in District Cooling Systems (DCS). The effect of the fluids on cost and cooling capacities were considered for the two cases of new and existing DCS separately. Two criteria were used in comparisons among fluids in each case: constant pumping power which allows for the most benefit, and constant velocity which is more practical consideration. An economic assessment for a 500 ton system shows a potential cost difference in the total pipe cost for a new system of 70% when a 30% ice slurry is used in place of chilled water. The pipe diameter is reduced to 40% using the slurry. These results apply to the constant comparison and are independent of the use of additive. Friction reduction additives serve to reduce pumping power and pressure drop. The ice-water slurry also has a significant impact on existing district cooling systems. It can potentially expand the cooling capacity by 500% without new piping being installed while maintaining the same pumping power, velocity and pressure-drop as the chilled water system. Again, friction reduction additives serve to reduce pumping power and pressure-drop. They do not influence cooling capacity. The cost for expanding the piping to increase the cooling capacity by the same amount by the use of conventional district cooling technology has been shown to be extremely high compared to the ice-water slurry system.
Choi, U.S. [Argonne National Lab., IL (United States); France, D.M.; Knodel, B.D. [Argonne National Lab., IL (United States)]|[Illinois Univ., Chicago, IL (United States). Dept. of Mechanical Engineering
Choi, U.S. (Argonne National Lab., IL (United States)); France, D.M.; Knodel, B.D. (Argonne National Lab., IL (United States) Illinois Univ., Chicago, IL (United States). Dept. of Mechanical Engineering)
Development of advanced low-temperature heat transfer fluids for district heating and cooling, final report
The feasibility of adding phase change materials (PCMS) and surfactants to the heat transfer fluids in district cooling systems was investigated. It increases the thermal capacity of the heat transfer fluid and therefore decreases the volume that needs to be pumped. It also increases the heat transfer rate, resulting in smaller heat exchangers. The thermal behavior of two potential PCMS,
Y. I. Cho; H. G. Lorsch
1992 National census for district heating, cooling and cogeneration
District energy systems are a major part of the energy use and delivery infrastructure of the United States. With nearly 6,000 operating systems currently in place, district energy represents approximately 800 billion BTU per hour of installed thermal production capacity, and provides over 1.1 quadrillion BTU of energy annually -- about 1.3% of all energy used in the US each year. Delivered through more that 20,000 miles of pipe, this energy is used to heat and cool almost 12 billion square feet of enclosed space in buildings that serve a diverse range of office, education, health care, military, industrial and residential needs. This Census is intended to provide a better understanding of the character and extent of district heating, cooling and cogeneration in the United States. It defines a district energy system as: Any system that provides thermal energy (steam, hot water, or chilled water) for space heating, space cooling, or process uses from a central plant, and that distributes the energy to two or more buildings through a network of pipes. If electricity is produced, the system is a cogenerating facility. The Census was conducted through surveys administered to the memberships of eleven national associations and agencies that collectively represent the great majority of the nation`s district energy system operators. Responses received from these surveys account for about 11% of all district systems in the United States. Data in this report is organized and presented within six user sectors selected to illustrate the significance of district energy in institutional, community and utility settings. Projections estimate the full extent of district energy systems in each sector.
Not Available
Optimal energy transmission fluids for District Heating and Cooling applications
Argonne National Laboratory under sponsorship of the US DOE Office of Buildings and Community Systems has embarked upon a comprehensive program to develop high performance energy transmission fluids for use in district Heating and cooling (DHC) Systems. These fluids would substantially reduce flow frictional losses and enhance heat transfer. The fluids have been shown in system enhancement scoping studies conducted
K. E. Kasza; J. Kaminsky
Modular cogeneration in district heating and cooling systems
The use of prepackaged cogeneration systems of modular size (100 kWe - 10 MWe) in conjunction with district heating and cooling is proposed as a way to enhance the energy conservation potential of both cogeneration and district energy systems. This report examines the technical and institutional aspects of this marriage of technologies, and develops a research agenda whose goal is to define this potential use of cogeneration more accurately and to develop the generic technology base needed to bring it to actuality. 11 refs.
Andrews, J.W.; Aalto, P.; Gleason, T.C.J.; Skalafuris, A.J.
Immersion/two phase cooling
NASA Astrophysics Data System (ADS)
Due to increasing heat dissipation requirements, the need for an advanced cooling technique in current military avionics has been recognized. Immersion cooling with phase change has been demonstrated in a Format E clamshell module as an alternative. This module is capable of dissipating more than 700 Watts. From the development of the Format E clamshell module the AAS&T (Advanced Avionics Subsystems and Technology) Program has begun an effort to utilize the clamshell module in the development of a 3/4 ATR Format E Standard Avionics Enclosure utilizing immersion/change of phase cooling. The power dissipation requirement for the enclosure is 6500 Watts minimum. The cooling medium for both efforts is a Fluorinert (FS-72). The FS-72 is an environmentally safe coolant. As the need for greater heat removal and reliability increases, cooling technology must become more advanced to meet the needs of next generation aircraft.
Jones, Jack; Perkoski, Emmett
District heating and cooling systems for communities through power plant retrofit distribution network. Phase 2. Final report, March 1, 1980-January 31, 1984. Volume IV
This volume contains the following: discussion of cost estimating methodology, detailed cost estimates of Hudson No. 2 retrofit, intermediate thermal plant (Kearny No. 12) and local heater plants; transmission and distribution cost estimate; landfill gas cost estimate; staged development scenarios; economic evaluation; fuel use impact; air quality impact; and alternatives to district heating.
Optimal energy transmission fluids for district heating and cooling applications
The US Department of Energy is sponsoring the development of improving energy transmission fluids for district heating and cooling applications. This long-range-program has as its objectives: (1) identifying and developing high performance thermal-hydraulic energy transmission fluids and the components to best utilize the fluids in DHC systems; (2) demonstrating that these fluids substantially reduce frictional losses and improve heat transfer,
R And D Pilot Plant Project for Evaluating a Direct Freeze Ice Slurry Based District Cooling System: Revised Final Report.
This report quantifies the potential for an ice slurry district cooling system based on an innovative direct freeze ice production technology as part of the US Department of Energy project ''District Heating and Cooling Technology Research: District Cooli...
B. D. Knodel
Environmental and health benefits of district cooling using utility-based cogeneration in Ontario, Canada
Environmental and health benefits are shown to be possible in the province of Ontario by using heat cogenerated from the facilities of the main provincial electrical utility, Ontario Hydro, to drive absorption chillers which supply the cooling needs of district-cooling networks in the province. Two district-cooling scenarios are assessed. The first assumes implementation of utility-based cogeneration\\/absorption chilling to satisfy a
Donald R. Hart; Marc A. Rosen
A novel concept for heat transfer fluids used in district cooling systems
Low-temperature phase-change materials (PCMS) were mixed with water to enhance the performance of heat transfer fluid. Several PCMs were tested in a laboratory-scale test loop to check their suitability to district cooling applications. The phase-change temperatures and latent heats of fusion of tetradecane, pentadecane, and hexadecane paraffin waxes were measured using a differential scanning calorimeter. The heat of fusion of these materials is approximately 60% of that of ice. They exhibit no supercooling and are stable under repeated thermal cycling. For 10% and 25% PCM-water slurries, the heat transfer enhancement was found to be approximately 18 and 30 percent over the value of water, respectively. It was also found that, in the turbulent region, there is only a minor pumping penalty from the addition of up to 25% PCM to the water. It was demonstrated that pentadecane does not clog in a glass-tube chiller, and continuous pumping below its freezing, point (9.9[degrees]C):was successfully carried out in a bench-scale flow loop. Adding PCM to water increases the thermal capacity of the heat transfer fluid and therefore decreases the volume that needs to be pumped in a district cooling system. It also increases the heat transfer rate, resulting in smaller heat exchangers. Research is continuing on these fluids in order to determine their behavior in large-size loops and to arrive at optimum formulations.
Cho, Y.I.; Choi, E.; Lorsch, H.G.
Development of advanced low-temperature heat transfer fluids for district heating and cooling
The feasibility of adding phase change materials (PCMs) and surfactants to the heat transfer fluids in district cooling systems was investigated. It increases the thermal capacity of the heat transfer fluid and therefore decreases the volume that needs to be pumped. It also increases the heat transfer rate, resulting in smaller heat exchangers. The thermal behavior of two potential PCMs, hexadecane and tetradecane paraffin wax, was experimentally evaluated. The heat of fusion of these materials is approximately 60% of that of ice. They exhibit no supercooling and are stable under repeated thermal cycling. While test results for laboratory grade materials showed good agreement with data in the literature, both melting point and heat of fusion for commercial grade hexadecane were found to be considerably lower than literaturevalues. PCM/water mixtures were tested in a laboratory-scale test loop to determine heat transfer and flow resistance properties. When using PCMs in district cooling systems, clogging of frozen PCM particles isone of the major problems to be overcome. In the present project it is proposed to minimize or prevent clogging by the addition of an emulsifier. Effects of the emulsifier on the mixture of water and hexadecane(a PCM) were studied. As the amount of the emulsifier was increased, the size of the solid PCM particles became smaller. When the size of the particles was small enough, they did not stick together or stick to the cold surface of a heat exchanger. The amount of emulsifier to produce this condition was determined.
Two phase cooling for superconducting magnets
Comments on the use of two phase helium in a closed circuit tubular cooling system and some results obtained with the TPC superconducting magnet are given. Theoretical arguments and experimental evidence are given against a previously suggested method to determine helium two phase flow regimes. Two methods to reduce pressure in the magnet cooling tubes during quenches are discussed; (1) lowering the density of helium in the magnet cooling tubes and (2) proper location of pressure relief valves. Some techniques used to protect the refrigerator from too much cold return gas are also mentioned. 10 refs., 1 fig., 5 tabs.
Eberhard, P.H.; Gibson, G.A.; Green, M.A.; Ross, R.R.; Smits, R.G.; Taylor, J.D.; Watt, R.D.
Reduction of pumping energy losses in district heating and cooling systems
This project was designed to find effective surfactant friction reducing additives for use in district heating systems with temperatures of 50 to 90[degrees]C and effective additives fore district cooling systems with temperatures of 5 to 15[degrees]C. Heat transfer measurements in conventional shell and tube heat exchangers and in plate heat exchangers were also carried out to see how seriously these surfactant drag reducing additives reduce heat transfer coefficients.
Zakin, J.L.; Christensen, R.N.
Reduction of pumping energy losses in district heating and cooling systems. Final report
This project was designed to find effective surfactant friction reducing additives for use in district heating systems with temperatures of 50 to 90{degrees}C and effective additives fore district cooling systems with temperatures of 5 to 15{degrees}C. Heat transfer measurements in conventional shell and tube heat exchangers and in plate heat exchangers were also carried out to see how seriously these surfactant drag reducing additives reduce heat transfer coefficients.
DOE grant for assessment of district cooling system for University of Arkansas for Medical Sciences, Little Rock, Arkansas.
The object of this study which covers the assessment of the District Cooling Plant for the University of Arkansas for Medical Sciences (UAMS) Campus, was to study potential ways to use the newest technology in District Cooling and Methodology to optimize ...
R. W. Timmerman W. T. F. Broer
Heat and Mass Transfer in Polyurethane Insulated District Cooling and Heating Pipes
The heat and mass transfer in PUR insulated pipes used for dis trict cooling and district heating is studied. During the aging of the pipes, the blowing agent, in this study CO2 for the PUR foam will diffuse out through the casing and air components will diffuse into the foam. This diffusion will deterio rate the thermal properties of the
Daniel Eriksson; Bengt Sund�n
A novel concept for heat transfer fluids used in district cooling systems. Progress report, September 25, 1990--December 31, 1990
Low-temperature phase-change materials (PCMS) were mixed with water to enhance the performance of heat transfer fluid. Several PCMs were tested in a laboratory-scale test loop to check their suitability to district cooling applications. The phase-change temperatures and latent heats of fusion of tetradecane, pentadecane, and hexadecane paraffin waxes were measured using a differential scanning calorimeter. The heat of fusion of these materials is approximately 60% of that of ice. They exhibit no supercooling and are stable under repeated thermal cycling. For 10% and 25% PCM-water slurries, the heat transfer enhancement was found to be approximately 18 and 30 percent over the value of water, respectively. It was also found that, in the turbulent region, there is only a minor pumping penalty from the addition of up to 25% PCM to the water. It was demonstrated that pentadecane does not clog in a glass-tube chiller, and continuous pumping below its freezing, point (9.9{degrees}C):was successfully carried out in a bench-scale flow loop. Adding PCM to water increases the thermal capacity of the heat transfer fluid and therefore decreases the volume that needs to be pumped in a district cooling system. It also increases the heat transfer rate, resulting in smaller heat exchangers. Research is continuing on these fluids in order to determine their behavior in large-size loops and to arrive at optimum formulations.
Application of imitation steam'' systems to hot water district heating and cooling systems
Pequod Associates, Inc. and District Energy St. Paul, Inc. installed a pilot project of an innovative District Heating technology through a contract with the US DOE. This applied research was funded by the Energy Research and Development Act (94--163) for District Heating and Cooling Research. The experimental design is an intervention technique that permits hot water district heating systems to connect to buildings equipped with steam heating systems to connect to buildings equipped with steam heating systems. This method can substantially reduce conversion costs in many older buildings. The method circulates Imitation Steam, which is moist hot air, as a heating medium in standard steam radiators and steam heating coils. Based on the operation of the system during the 1989--90 and 1990--91 winter heating seasons, we conclude the following: the basic concept of using Imitation Steam was proved feasible. The performance of the system can be improved beyond the levels achieved in this installation. Imitation Steam did not cause significant corrosion in the piping system. The technology can be used by other district heating systems to lower conversion costs and increase market penetration. Among the additional benefits from this technology are: eliminating old, inefficient boilers; lower maintenance costs; improved fuel efficiency; reduced emissions.
Aalto, P.J.; Chen, D.B.
A closed circuit tubular cooling system for superconducting magnets offers advantages of limiting boiloff and containing high pressures during quenches. Proper location of automatic valves to lower pressures and protect the refrigerator in the event of quenches is described. Theoretical arguments and exprimental evidence are given against a previously suggested method to determine He two phase flow regimes. If loss of flow occurs due to some types of refrigeration failure and transfer lines have enough heat leak to warm up, quenches are induced when the flow is restored. Examples are taken from experience with the TPC magnet.
This project was designed to explore the effects of different structures of cationic surfactant drag reducing additives on their efficiency and on their effective temperature ranges. The goal was to develop surfactant systems that would be useful in the appropriate temperature ranges for district heating systems (50--110{degree}C) and for district cooling systems (2--20{degree}C). To this end the chemical compositions of quaternary annonium salts and of counter-ions were varied. More than twenty different commercial or semi commercial quarterly ammonium salts from US suppliers and two from a German supplier (Hoechst) were tested along with thirty five different counter-ions. In addition, blends of several of each were also tested. A further object of this project was to check the compatibility of surfactant drag reducers with commercial or semi-commercial corrosion inhibitors in regard to maintaining their drag reducing ability and corrosion inhibiting capability.
Zakin, J.L.
User Manual for AQUASTOR: a Computer Model for Cost Analysis of Aquifer Thermal-Energy Storage Oupled with District-Heating or -Cooling Systems. Volume II. Appendices.
A computer model called AQUASTOR was developed for calculating the cost of district heating (cooling) using thermal energy supplied by an aquifer thermal energy storage (ATES) system. the AQUASTOR Model can simulate ATES district heating systems using sto...
H. D. Huber D. R. Brown R. W. Reilly
Phase space exchange in thick wedge absorbers for ionization cooling
The problem of phase space exchange in wedge absorbers with ionization cooling is discussed. The wedge absorber exchanges transverse and longitudinal phase space by introducing a position-dependent energy loss. In this paper we note that the wedges used with ionization cooling are relatively thick, so that single wedges cause relatively large changes in beam phase space. Calculation methods adapted to
David Neuffer
District heating and cooling assessment for the city of Ogden, Utah: Final report
District heating and cooling (DHC) is the process of supplying thermal energy in the form of hot water, steam, or chilled water from one or more central plants through a pipe distribution network to multiple customers. The thermal energy is used by the customers for space and water heating, space cooling, or industrial process requirements. During the past several decades the technologies and development of district heating systems have been relegated to providing steam to industries, university campuses, and military installations. There are also aging steam systems supplying energy to central business districts in some of the larger urban centers, primarily in the Northeast and Midwest. Meanwhile, European cities have developed modern and efficient systems using hot water serving entire cities. Since the 1972--1974 oil embargo, a better understanding of the role energy plays in urban areas has emerged. Ogden City has recognized this role and begun to identify methodologies and technologies that will allow the city to better manage its energy future. As part of the city's strategy, an Energy Task Force was established in 1981 by the Ogden City Council to study energy use in the community. A comprehensive energy plan developed by the Task Force was formally adopted by the Council in 1982 and made a part of the city's comprehensive plan. A twelve member Energy Commission was also established at this time to meet periodically and work toward implementing the goals of the plan on a community wide basis. A copy of the Energy Plan can be found as Appendix 1. 53 figs.
The problem of phase space exchange in wedge absorbers with ionization cooling is discussed. The wedge absorber exchanges transverse and longitudinal phase space by introducing a position-dependent energy loss. In this paper we note that the wedges used with ionization cooling are relatively thick, so that single wedges cause relatively large changes in beam phase space. Calculation methods adapted to such ''thick wedge'' cases are presented, and beam phase-space transformations through such wedges are discussed.
Neuffer, David [Fermilab, PO Box 500, Batavia, Illinois 60510 (United States)
Application of phased cooling to a once-through cooling system
A description is given of an application of a heat dissipation technique called phased-cooling to the cooling of once-through river water used in an electric power plant. A thermodynamic model for the situation is developed and the equations applying to the model are given. The performance of the system is analyzed for a summer day in the Southeastern United States.
J. A. MacFarlane; G. Maples; D. F. Dyer
Emerging Two-Phase Cooling Technologies for Power Electronic Inverters
In order to meet the Department of Energy's (DOE's) FreedomCAR and Vehicle Technologies (FVCT) goals for volume, weight, efficiency, reliability, and cost, the cooling of the power electronic devices, traction motors, and generators is critical. Currently the power electronic devices, traction motors, and generators in a hybrid electric vehicle (HEV) are primarily cooled by water-ethylene glycol (WEG) mixture. The cooling fluid operates as a single-phase coolant as the liquid phase of the WEG does not change to its vapor phase during the cooling process. In these single-phase systems, two cooling loops of WEG produce a low temperature (around 70 C) cooling loop for the power electronics and motor/generator, and higher temperature loop (around 105 C) for the internal combustion engine. There is another coolant option currently available in automobiles. It is possible to use the transmission oil as a coolant. The oil temperature exists at approximately 85 C which can be utilized to cool the power electronic and electrical devices. Because heat flux is proportional to the temperature difference between the device's hot surface and the coolant, a device that can tolerate higher temperatures enables the device to be smaller while dissipating the same amount of heat. Presently, new silicon carbide (SiC) devices and high temperature direct current (dc)-link capacitors, such as Teflon capacitors, are available but at significantly higher costs. Higher junction temperature (175 C) silicon (Si) dies are gradually emerging in the market, which will eventually help to lower hardware costs for cooling. The development of high-temperature devices is not the only way to reduce device size. Two-phase cooling that utilizes the vaporization of the liquid to dissipate heat is expected to be a very effective cooling method. Among two-phase cooling methods, different technologies such as spray, jet impingement, pool boiling and submersion, etc. are being developed. The Oak Ridge National Laboratory (ORNL) is leading the research on a novel floating refrigerant loop that cools high-power electronic devices and the motor/generator with very low cooling energy. The loop can be operated independently or attached to the air conditioning system of the vehicle to share the condenser and other mutually needed components. The ability to achieve low cooling energy in the floating loop is attributable to the liquid refrigerant operating at its hot saturated temperature (around 50 C+). In an air conditioning system, the liquid refrigerant is sub-cooled for producing cool air to the passenger compartment. The ORNL floating loop avoids the sub-cooling of the liquid refrigerant and saves significant cooling energy. It can raise the coefficient of performance (COP) more than 10 fold from that of the existing air-conditioning system, where the COP is the ratio of the cooled power and the input power for dissipating the cooled power. In order to thoroughly investigate emerging two-phase cooling technologies, ORNL subcontracted three university/companies to look into three leading two-phase cooling technologies. ORNL's assessments on these technologies are summarized in Section I. Detailed descriptions of the reports by the three university/companies (subcontractors) are in Section II.
Hsu, J.S.
Optimization of the engineering design for the Lansing District Cooling System by comparative analysis of the impact of advanced technologies on a conventional design approach. Volume 1
The Lansing Board of Water and Light (LBWL) began investigating development of a cooling district in the Lansing Downtown in 1989 in order to retain and build summer load for its steam utility. A feasibility study was conducted in conjunction with SFT, Inc. and ZBA, Inc. which addressed many factors such as marketability of the product, impact on the summer steam load, distribution system development, system design, probable capital and operating costs, reliability and environmental and other regulatory impacts on a preliminary feasibility basis. The Phase I study completed in September of 1989 provided highly promising results for establishing a District Cooling System (DCS). An existing chilled water production facility owned by the State of Michigan was identified as a potential location for a DCS plant. With these changes a review of the feasibility with a new set of alternatives and sensitivities was evaluated. This enhancement to the Phase I Study was nearing completion when the LBWL in conjunction with Energy, Mines and Resources Canada proposed to conduct the Phase II project in conjunction with DOE. The project was structured to proceed along a dual track to demonstrate the impact of the application of various innovative technologies.
Muon Capture, Phase Rotation, and Cooling in Pressurized RF Cavities
Gas-filled rf cavities can provide high-gradient accelerating fields for muons, and can be used for simultaneous acceleration and cooling of muons. In this paper we explore using these cavities in the front-end of the capture and cooling systems for neutrino factories and muon colliders. We consider using gas-filled rf cavities for the initial front end cooling systems. We also consider using them for simultaneous phase-energy rotation and cooling in a front-end system. We also consider using lower-density rf cavities, where the gas density is primarily for rf breakdown suppression, with less cooling effect. Pressurized rf cavities enable higher gradient rf within magnetic fields than is possible with evacuated cavities, enabling more options in the front-end. The status of designs of the capture, phase rotation, and precooling systems of muon beams in pressurized cavities is described.
Neuffer, D.; /Fermilab; Ankenbrandt, C.; Johnson, R.; Yoshikawa, C.; /Muons Inc., Batavia
The problem of phase space exchange in wedge absorbers with ionization cooling is discussed. The wedge absorber exchanges transverse and longitudinal phase space by introducing a position-dependent energy loss. In this paper we note that the wedges used with ionization cooling are relatively thick, so that single wedges cause relatively large changes in beam phase space. Calculation methods adapted to such {open_quotes}thick wedge{close_quotes} cases are presented, and beam phase-space transformations through such wedges are discussed. {copyright} {ital 1998 American Institute of Physics.}
Neuffer, D. [Fermilab, PO Box 500, Batavia, Illinois 60510 (United States)
Two-Phase Cooling Method Using the R134a Refrigerant to Cool Power Electronic Devices
This paper presents a two-phase cooling method using the R134a refrigerant to dissipate the heat energy (loss) generated by power electronics (PEs), such as those associated with rectifiers, converters, and inverters for a specific application in hybrid-electric vehicles. The cooling method involves submerging PE devices in an R134a bath, which limits the junction temperature of PE devices while conserving weight
Jeremy B. Campbell; Leon M. Tolbert; Curtis William Ayers; Burak Ozpineci; Kirk T. Lowe
Two-phase cooling method using R134a refrigerant to cool power electronic devices
This paper presents a two-phase cooling method using R134a refrigerant to dissipate the heat energy (loss) generated by power electronics (PE) such as those associated with rectifiers, converters, and inverters for a specific application in hybrid-electric vehicles (HEVs). The cooling method involves submerging PE devices in an R134a bath, which limits the junction temperature of PE devices while conserving weight
Jeremy B. Campbell; Leon M. Tolbert; Curt W. Ayers; Burak Ozpineci
We describe several storage ring designs for reducing the 6-dimensional phase space of circulating muon beams. These rings utilize quadrupole and dipole magnets as well as wedge-shaped, liquid-hydrogen, energy-loss absorbers and energy compensating rf cavities. We obtain evaluations of their cooling performance by particle tracking simulation. Such rings are potentially useful for future Neutrino Factories or Muon Colliders as well as for existing facilities in which cooled, intense muon beams could enhance their physics programs.
Development of advanced low-temperature heat transfer fluids for district heating and cooling. Final report, September 25, 1990--September 24, 1991
Feasibility of energy recovery for heat pump-assisted district heating and cooling from the Metro Renton wastewater treatment plant and effluent transfer system
The Municipality of Metropolitan Seattle (Metro) is constructing a 12-mile effluent transfer system (ETS) from its Renton wastewater treatment plant to Duwamish Head on Puget Sound. The preliminary stud (Phase I) concluded that the Renton treatment plant's effluent could feasibly sustain large amounts of heat pump output, i.e., 500 to 800 million Btu per hour. Further, the study identified eight locations along the ETS where district heating and cooling (DHC) networks could be favorably established to serve existing businesses and/or new growth. In December 1985 this second phase study was commissioned as a detailed assessment of specific customers in several of the recommended DHC development areas. The potential customers evaluated in this report include: Seattle-Tacoma International Airport, the Container Corporation carton manufacturing plant adjacent to the Renton treatment plant, Metro Transit Department's South Base, two buildings at the Boeing Developmental Center, and the Valley 405 Business Park adjacent to the Renton treatment plant. These potential users of effluent-based heating and/or cooling have been evaluated in terms of their heating and cooling demands, the type of effluent-based heat pump system necessary for serving them, and the economics of the effluent-based energy approach. In the cases of Sea-Tac and Container Corporation, the assessments also examine environmental and institutional issues, and generalized feasibilities for financing effluent-based systems.
Enhanced cooling capacities of ferroelectric materials at morphotropic phase boundaries
The electrocaloric properties of PbZr0.52Ti0.48O3 (PZT) epitaxial films and 0.7Pb(Mg1/3Nb2/3)O3-0.3PbTiO3 (0.7PMN-0.3PT) single crystals are measured and demonstrated enhanced low temperature refrigeration at morphotropic phase boundary compositions. The results reveal large adiabatic cooling figures in ~260 nm PZT films (11 K in 15 V) and 200 ?m thick 0.7PMN-0.3PT single crystals (2.7 K in 240 V) at Curie transition temperatures and secondary cooling peaks at lower temperatures, near critical points. This is a very useful aspect of ferroelectric cooling elements to attain effective cooling over wide range of working temperatures in solid-state devices.
Chukka, Rami; Cheah, Jun Wei; Chen, Zuhuang; Yang, P.; Shannigrahi, S.; Wang, Junling; Chen, Lang
Energy efficient two-phase cooling for concentrated photovoltaic arrays
Concentrated sunlight focused on the aperture of a photovoltaic solar cell, coupled with high efficiency, triple junction cells can produce much greater power densities than traditional 1 sun photovoltaic cells. However, the large concentration ratios will lead to very high cell temperatures if not efficiently cooled by a thermal management system. Two phase, flow boiling is an attractive cooling option for such CPV arrays. In this work, two phase flow boiling in mini/microchannels and micro pin fin arrays will be explored as a possible CPV cooling technique. The most energy efficient microchannel design is chosen based on a least-material, least-energy analysis. Heat transfer and pressure drop obtained in micro pin fins will be compared to data in the recent literature and new correlations for heat transfer coefficient and pressure drop will be presented. The work concludes with an energy efficiency comparison of micro pin fins with geometrically similar microchannel geometry.
Reeser, Alexander Douglas
Two-phase flow instability analysis for transient electronics cooling
Because of increasing power densities, refrigeration systems are being explored for two-phase cooling of ultra high power electronic components. This paper presents a framework for the transient analysis of pressure-drop refrigerant flow instabilities under both steady-state and transient imposed heat loads. Based on an analytical two-phase flow model, the system pressure and other effects on flow characteristics are quantitatively studied,
TieJun Zhang; Yoav Peles; John T. Wen; Michael K. Jensen
Geothermal district heating systems
Ten district heating demonstration projects and their present status are described. The projects are Klamath County YMCA, Susanville District Heating, Klamath Falls District Heating, Reno Salem Plaza Condominium, El Centro Community Center Heating/Cooling, Haakon School and Business District Heating, St. Mary's Hospital, Diamond Ring Ranch, Pagosa Springs District Heating, and Boise District Heating.
Budney, G. S.; Childs, F.
Two-Phase Closed-Loop Thermosyphon for Electronic Cooling
This study experimentally investigated the thermal performance of a two-phase closed-loop thermosyphon with a thermal resistance model for electronic cooling. The evaporator, rising tube, condenser, and falling tube, which are the four main devices, formed a closed-loop system with water as the working fluid. The experimental parameters were the evaporator surface type, fill ratio of working fluid, and input heating
C.-C. Chang; S.-C. Kuo; M.-T. Ke; S.-L. Chen
Liouville`s theorem and phase-space cooling
A discussion is presented of Liouville`s theorem and its consequences for conservative dynamical systems. A formal proof of Liouville`s theorem is given. The Boltzmann equation is derived, and the collisionless Boltzmann equation is shown to be rigorously true for a continuous medium. The Fokker-Planck equation is derived. Discussion is given as to when the various equations are applicable and, in particular, under what circumstances phase space cooling may occur.
Mills, R.L. [Ohio State Univ., Columbus, OH (United States); Sessler, A.M. [Lawrence Berkeley Lab., CA (United States)
Conduction phase change beneath insulated heated or cooled structures
The problem of thawing beneath heated structures on permafrost (or cooled structures in non-permafrost zones) must be addressed if safe engineering designs are to be conceived. In general, there are no exact solutions to the problem of conduction heat transfer with phase change for practical geometries. The quasi-steady approximation is used here to solve the conductive heat transfer problem with phase change for insulated geometries including infinite strips, rectangular buildings, circular storage tanks, and buried pipes. Analytical solutions are presented and graphed for a range of parameters of practical importance.
Lunardini, V. J.
Santa Ana Pueblo assessment of district heating and cooling. Final report, 1981-1982
The Santa Ana Pueblo American Indian Tribe, numbering approximately 600 persons occupies two sites, totalling about 60,000 acres, northwest of Albuquerque, New Mexico. With the aid of consultants it has investigated the community's use of energy and a number of sources of fuel to supply a district heating system. The most promising heat source is the production of methane gas
H. Jenkins; M. Giddings
Optics for Phase Ionization Cooling of Muon Beams
The realization of a muon collider requires a reduction of the 6D normalized emittance of an initially generated muon beam by a factor of more than 106. Analytical and simulation studies of 6D muon beam ionization cooling in a helical channel filled with pressurized gas or liquid hydrogen absorber indicate that a factor of 106 is possible. Further reduction of the normalized 4D transverse emittance by an additional two orders of magnitude is envisioned using Parametric-resonance Ionization Cooling (PIC). To realize the phase shrinkage effect in the parametric resonance method, one needs to design a focusing channel free of chromatic and spherical aberrations. We report results of our study of a concept of an aberration-free wiggler transport line with an alternating dispersion function. Resonant beam focusing at thin beryllium wedge absorber plates positioned near zero dispersion points then provides the predicted PIC effect.
R.P. Johnson; S.A. Bogacz; Y.S. Derbenev
Advanced heat pump cycle for district heating and cooling systems. Second quarterly progress report
A new scheme to significantly improve the performance of the two stage vapor compression cycle by eliminating the rectifier was first investigated with the help of computer simulation, and then incorporated in the experimental setup. Simulation results show that the cycle with a bleed line (modified cycle without the rectifier) has 20 to 30% higher cooling COP as compared to the cycle with the rectifier. It is important to note that this improvement in COP is accompanied by 10 to 15% increase in cooling load. Initial experimental results along with operating experience and description of the data acquisition program are presented here. Results show that hear can be pumped from an average temperature of 0{degrees}C to an average temperature of 100{degrees}C with a pressure ratio as low as 7.1. Cooling COPs up to 1.0 were obtained for cooling loads of about 4.17 kW.
Radermacher, R.
User manual for GEOCITY: a computer model for cost analysis of geothermal district-heating-and-cooling systems. Volume II. Appendices
The purpose of this model is to calculate the costs of residential space heating, space cooling, and sanitary water heating or process heating (cooling) using geothermal energy from a hydrothermal reservoir. The model can calculate geothermal heating and cooling costs for residential developments, a multi-district city, or a point demand such as an industrial factory or commercial building. Volume II contains all the appendices, including cost equations and models for the reservoir and fluid transmission system and the distribution system, descriptions of predefined residential district types for the distribution system, key equations for the cooling degree hour methodology, and a listing of the sample case output. Both volumes include the complete table of contents and lists of figures and tables. In addition, both volumes include the indices for the input parameters and subroutines defined in the user manual.
Huber, H.D.; Fassbender, L.L.; Bloomster, C.H.
Exhaust Heat CoGeneration System Using Phase Change Cooling for Heavy Duty Vehicle
A waste heat recovery system composed of a two phase cooling system, an exhaust heat exchanger, and mini-turbine (expander) has been proposed by Henry Works, Inc to generate auxiliary power via harvesting engine cooling and exhaust heat loss from heavy duty vehicles. The objective of this research is to evaluate the two phase cooling system through engine dynamometer testing and
Kiran K. Katta; Myoungjin Kim; Mike Taggett
In order to meet the Department of Energy's (DOE's) FreedomCAR and Vehicle Technologies (FVCT) goals for volume, weight, efficiency, reliability, and cost, the cooling of the power electronic devices, traction motors, and generators is critical. Currently the power electronic devices, traction motors, and generators in a hybrid electric vehicle (HEV) are primarily cooled by water-ethylene glycol (WEG) mixture. The cooling
Cooling of Sr to high phase-space density by laser and sympathetic cooling in isotopic mixtures
Based on an experimental study of two-body and three-body collisions in ultracold strontium samples, a novel optical-sympathetic cooling method in isotopic mixtures is demonstrated. Without evaporative cooling, a phase-space density of 6x10{sup -2} is obtained with a high spatial density that should allow us to overcome the difficulties encountered so far to reach quantum degeneracy for Sr atoms.
Ferrari, G.; Drullinger, R. E.; Poli, N.; Sorrentino, F.; Tino, G. M. [Dipartimento di Fisica and LENS, Istituto Nazionale Fisica Nucleare, Istituto Nazionale Fisica della Materia, Polo Scientifico-Universita di Firenze, 50019 Sesto Fiorentino (Italy)
Open cycle heat pump development for local resource use. Phase 2: District heating case study analysis
District heating (DH) systems provide thermal energy to their customers in the form of hot water or steam. These systems can use one or more types of heat sources to meet the thermal load, including boilers, cogeneration systems, or low-grade heat sources in conjunction with a heat pump. Most large-scale heat pumps operate using the closed-cycle concept and usually use a chlorinated fluorocarbon (CFC) as the working fluid. An alternative to this approach is the quasi open-cycle heat pump, which was first studied in a Phase 1 report entitled, Open-Cycle Heat Pump Development for Local Resource Use, DOE/CE/26563-5. The quasi open-cycle (QOC) heat pump actually uses the district heating transport medium as its working fluid. This document is the Final Report prepared as a part of Task 6 of Open-Cycle Heat Pump Development for Local Resource Use, Phase 2 District Heating Case Study Analysis. The objective of this study contract was to assess the application of the QOC heat pump in an actual case study.
Patch, K. D.; Dibella, F. A.; Glick, J. F.; Becker, F. E.
Quark beta decay in the inhomogeneous chiral phase and cooling of compact stars
A novel cooling mechanism is proposed for neutron stars, based on the recent development in the studies of the QCD phase diagram. A possible appearance of the inhomogeneous chiral phase makes the quark beta decay without gluonic interaction. An estimate of the neutrino emissivity shows the order of 1024-26(T/109)61ex" (erg cm-3 s-11ex" ) near the phase boundaries, whose efficiency is comparable with the usual quark cooling or pion cooling, but it works only in the limited density region. These features may give another cooling scenario of neutron stars.
Tatsumi, T.; Muto, T.
Extremum seeking micro-thermal-fluid control for active two-phase microelectronics cooling
To address increasing power densities in high power electronic devices, microchannel systems operating in the two-phase regime have been explored in recent years for high heat flux cooling applications. However, flow and thermal oscillations, frequently present in two-phase microchannel cooling, may severely compromise the cooling performance and system integrity. This paper considers the thermal-fluid control of a microchannel evaporator by
Tiejun Zhang; John T. Wen; Agung Julius; Yoav Peles; Michael K. Jensen
Two-Phase Thermosyphon Device for the Large Thyristor Cooling.
The paper reports on the design of a new advanced air-cooled heat sink device for the cooling of large thyristors, with silicon wafers (75 and 100 mm diameters) and their dissipating auxiliary components, such as snubber resistors. This device, consisting...
P. Bordignon A. Ragni E. Latrofa C. Casarosa
Photoreversible micellar solution as a smart drag-reducing fluid for use in district heating/cooling systems.
A photoresponsive micellar solution is developed as a promising working fluid for district heating/cooling systems (DHCs). It can be reversibly switched between a drag reduction (DR) mode and an efficient heat transfer (EHT) mode by light irradiation. The DR mode is advantageous during fluid transport, and the EHT mode is favored when the fluid passes through heat exchangers. This smart fluid is an aqueous solution of cationic surfactant oleyl bis(2-hydroxyethyl)methyl ammonium chloride (OHAC, 3.4 mM) and the sodium salt of 4-phenylazo benzoic acid (ACA, 2 mM). Initially, ACA is in a trans configuration and the OHAC/ACA solution is viscoelastic and exhibits DR (of up to 80% relative to pure water). At the same time, this solution is not effective for heat transfer. Upon UV irradiation, trans-ACA is converted to cis-ACA, and in turn, the solution is converted to its EHT mode (i.e., it loses its viscoelasticity and DR) but it now has a heat-transfer capability comparable to that of water. Subsequent irradiation with visible light reverts the fluid to its viscoelastic DR mode. The above property changes are connected to photoinduced changes in the nanostructure of the fluid. In the DR mode, the OHAC/trans-ACA molecules assemble into long threadlike micelles that impart viscoelasticity and DR capability to the fluid. Conversely, in the EHT mode the mixture of OHAC and cis-ACA forms much shorter cylindrical micelles that contribute to negligible viscoelasticity and effective heat transfer. These nanostructural changes are confirmed by cryo-transmission electron microscopy (cryo-TEM), and the photoisomerization of trans-ACA and cis-ACA is verified by (1)H NMR. PMID:23210742
Shi, Haifeng; Ge, Wu; Oh, Hyuntaek; Pattison, Sean M; Huggins, Jacob T; Talmon, Yeshayahu; Hart, David J; Raghavan, Srinivasa R; Zakin, Jacques L
Effect of Continuous Cooling on Secondary Phase Precipitation in the Super Duplex Stainless Steel ZERON-100
The precipitation of secondary phases in super duplex stainless steels (SDSS) is a subject of great relevance owing to their dangerous effects on both mechanical and corrosion-resistance properties. This paper examines the effect of continuous cooling after solution annealing treatment on secondary phase precipitation in the ZERON-100 SDSS. It considers the influence of cooling rate on volume fraction, morphology and chemical composition. It has been found that the formation of sigma and chi phases can be avoided only at cooling rates higher than 0.7 �C/s. In addition, at the lowest cooling rate the sigma phase amount approaches the equilibrium value, but the chi phase amount remains significantly low.
Calliari, Irene; Bassani, Paola; Brunelli, Katya; Breda, Marco; Ramous, Emilio
Cooling of Compact Stars with Quark-Hadron Mixed Phase in the Colour Superconductive State
Recently, the central source of Cassiopeia A (Cas A) has been observed, which indicates that the star has large mass and high effective temperature. We suspect that the compact object cools by the standard neutrino emission. We assume that the compact object contains quark matter with colour superconductivity and calculate cooling curves. Considering the Quark-Hadron Mixed Phase, we obtain cooling curves which are found to be consistent with the observations.
Noda, Tsuneo; Hashimoto, Masa-aki [Department of Physics, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka, 812-8581 (Japan); Yasutake, Nobutoshi [Division of Theoretical Astronomy, National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Maruyama, Toshiki [Advanced Science Research Center, Japan Atomic Energy Research Institute, Tokai, Ibaraki 319-1195 (Japan); Tatsumi, Toshitaka [Department of Physics, Kyoto University, Kitashirakawa-Oiwake-cho, Kyoto 606-8502 (Japan); Fujimoto, Masayuki [Department of Physics, Hokkaido University, Kita-10 Nishi-8, Kita-ku, Sapporo, Hokkaido 060-0810 (Japan)
An Experimental Investigation of Liquid Jet Impingement and Single-Phase Spray Cooling Using Polyalphaolefin
Experiments on triangular and rectangular array jet impingement and single-phase spray cooling have been performed to determine the effect of both cooling techniques on heat transfer coefficient (h) and the coolant mass flux required for a given cooling load. Experiments were performed with circular orifices and nozzles for different H\\/D values from 1.5 to 26 and Reynolds number range of
A. K. Sleiti; J. S. Kapat
MICE: The International Muon Ionization Cooling Experiment: Phase Space Cooling Measurement
MICE is an experimental demonstration of muon ionization cooling using a section of an ionization cooling channel and a muon beam. The muons are produced by the decay of pions from a target dipping into the ISIS proton beam at Rutherford Appleton Laboratory (RAL). The channel includes liquid-hydrogen absorbers providing transverse and longitudinal momentum loss and high-gradient radiofrequency (RF) cavities for longitudinal reacceleration, all packed into a solenoidal magnetic channel. MICE will reduce the beam transverse emittance by about 10% for muon momenta between 140 and 240 MeV/c. Time-of-flight (TOF) counters, threshold Cherenkov counters, and a calorimeter will identify background electrons and pions. Spectrometers before and after the cooling section will measure the beam transmission and input and output emittances with an absolute precision of 0.1%.
Hart, T. L.
Phase space control and consequences for cooling by using a laser-undulator beat wave
We present a general method to control the phase space structure of charged particle beams by both Hamiltonian and non-Hamiltonian manipulations by employing multiple optical pulses. In particular, we focus on beam cooling as an example of the method. In order to rapidly cool a bunched beam of charged particles, one needs to introduce non-Hamiltonian manipulation of the internal structure
Y. Kishimoti; James K. Koga; Toshiki Tajima; Y. Kishimoto; D. L. Fisher
Legionnaires' disease bacteria in power plant cooling systems: Phase 2
Legionnaires' Disease Bacteria (Legionella) are a normal component of the aquatic community. The study investigated various environmental factors that affect Legionella profiles in power plant cooling waters. The results indicate that each of the four factors investigated (incubation temperature, water quality, the presence and type of associated biota, and the nature of the indigenous Legionella population) is important in determining
R. L. Tyndall; S. W. Christensen; J. A. Solomon
Effect of the cooling rate on the phase composition and structure of copper matte converting slags
The effect of the cooling rate on the phase composition and microstructure of copper matte converting slags is studied by X-ray diffraction, combined thermogravimetry and calorimetry, mineragraphy, and electron-probe microanalysis. The compositions of oxide and sulfide phases are determined, and the forms of nonferrous metals in slags cooled at a rate of 0.3 and 900�C/s are revealed. At high cooling rates of the slags, iron silicate glass is shown to form apart from sulfide phases. Repeated heating of the slags leads to the development of devitrification, �cold� crystallization, and melting. A decrease in the cooling rate favors an increase in the grain sizes in oxides (magnetite, iron silicates) and sulfides (bornite-, sphalerite, and galena-based solid solutions).
Selivanov, E. N.; Gulyaeva, R. I.; Udoeva, L. Yu.; Belyaev, V. V.; Pankratov, A. A.
Planning for Quality Schools: Meeting the Needs of District Families. Phase One: Understanding Current School Supply and Student Enrollment Patterns
ERIC Educational Resources Information Center
This report is the first phase of a three-part Quality Schools Project to help the District of Columbia create a firm analytical basis for planning for quality schools to meet the needs of the city's families. The Quality School Project is a joint effort of the DC Office of the State Superintendent of Education, the 21st Century School Fund, the�
Garrison, David; Allen, Marni; Turner, Margery; Comey, Jennifer; Williams, Barika; Guernsey, Elizabeth; Filardo, Mary; Huvendick, Nancy; Sung, Ping
Computer cooling using a two phase minichannel thermosyphon loop heated from horizontal and vertical sides and cooled from vertical side
In the present paper it is proposed to consider the computer cooling capacity using the thermosyphon loop. A closed thermosyphon loop consists of combined two heaters and a cooler connected to each other by tubes. The first heater may be a CPU processor located on the motherboard of the personal computer. The second heater may be a chip of a graphic card placed perpendicular to the motherboard of personal computer. The cooler can be placed above the heaters on the computer chassis. The thermosyphon cooling system on the use of computer can be modeled using the rectangular thermosyphon loop with minichannels heated at the bottom horizontal side and the bottom vertical side and cooled at the upper vertical side. The riser and a downcomer connect these parts. A one-dimensional model of two-phase flow and heat transfer in a closed thermosyphon loop is based on mass, momentum, and energy balances in the evaporators, rising tube, condenser and the falling tube. The separate two-phase flow model is used in calculations. A numerical investigation for the analysis of the mass flux rate and heat transfer coefficient in the steady state has been accomplished.
Bieli?ski, Henryk; Mikielewicz, Jaros?aw
This report documents the Savannah River National Laboratory (SRNL) support for the Tank Closure and Technology Development (TCTD) group's strategy for closing high level radioactive waste (HLW) tanks at the Savannah River Site (SRS). Specifically, this task addresses the ability to successfully fill intact cooling coils, presently within the HLW tanks, with grout that satisfies the fresh and cured grout requirements [1] under simulated field conditions. The overall task was divided into two phases. The first phase was the development of a grout formulation that satisfies the processing requirements for filling the HLW tank cooling coils [5]. The second phase of the task, which is documented in this report, was the filling of full scale cooling coils under simulated field conditions using the grout formulation developed in the first phase. SRS Type I tank cooling coil assembly design drawings and pressure drop calculations were provided by the Liquid Waste (LW) customer to be used as the basis for configuring the test assemblies. The current concept for closing tanks equipped with internal cooling coils is to pump grout into the coils to inhibit pathways for infiltrating water. Access to the cooling coil assemblies is through the existing supply/return manifold headers located on top of the Type I tanks. The objectives for the second phase of the testing, as stated in the Task Technical and Quality Assurance plan (TTQAP) [2], were to: (1) Perform a demonstration test to assess cooling coil grout performance in simulated field conditions, and (2) Measure relevant properties of samples prepared under simulated field conditions. SRNL led the actual work of designing, fabricating and filling two full-scale cooling coil assemblies which were performed at Clemson Engineering Technologies Laboratory (CETL) using the South Carolina University Research and Education Foundation (SCUREF) program. A statement of work (SOW) was issued to CETL [6] to perform this work.
Hansen, E; Alex Cozzi, A
Characterization of Solid State Phase Transformation in Continuously Heated and Cooled Ferritic Weld Metal
Arc welding processes involve cooling rates that vary over a wide range (1-100 K/s). The final microstructire is thus a product of the heating and cooling cycles experienced by the weld in addition to the weld composition. It has been shown that the first phase to form under weld cooling conditions may not be that predicted by equilibrium calculations. The partitioning of different interstitial/substitutional alloying elements at high temperatures can dramatically affect the subsequent phase transformations. In order to understand the effect of alloying on phase transformation temperatures and final microstructures time-resolved X-ray diffraction technique has been successfully used for characterization. The work by Jacot and Rappaz on pearlitic steels provided insight into austenitization of hypoeutectic steels using a finite volume model. However there is very little work done on the effect of heating and cooling rates on the phase transformation paths in bainitic/martensitic steels and weld metals. Previous work on a weld with higher aluminum content, deposited with a FCAW-S process indicated that even at aluminum levels where the primary phase to solidify from liquid should be delta ferrite, non-equilibrium austenite was observed. The presence of inhomogeneity in composition of the parent microstructure has been attributed to differences in transformation modes, temperatures and microstructures in dual-phase, TRIP steels and ferritic welds. The objectives of the work included the identification of the stability regions of different phases during heating and cooling, differences in the effect of weld heating and cooling rates on the phase transformation temperatures, and the variation in phase fractions of austenite and ferrite in the two phase regions as a function of temperature. The base composition used for the present work is a Fe-1%Al-2%Mn-1%Ni-0.04%C weld metal. A pseudo-binary phase diagram shows the expected solidification path under equilibrium conditions. However, the effect of heating and cooling rates on the phase transformation path due to non-equilibrium partitioning of alloying elements cannot be predicted by equilibrium phase diagrams. Also, it is unclear if there is retention of delta ferrite to room temperature due to compositional or thermal effects. This would dramatically affect the austenite to ferrite transformation due to carbon and nitrogen enrichment in the austenite.
Narayana, B [Ohio State University, The, Columbus; Mills, Michael J. [Ohio State University, The, Columbus; Specht, Eliot D [ORNL; Santella, Michael L [ORNL; Babu, Sudarsanam Suresh [Ohio State University, The, Columbus
Modeling phase transformations in ternary systems: Ferrite dissolution during continuous cooling
The diffusion-controlled phase dissolution (or growth) in a ternary system of finite length has been modeled numerically using an implicit finite-difference method. The analysis has been applied to study the ferrite to austenite transformation in austenitic stainless steel weldments. The iron-chromium-nickel ternary system was taken as representative of this class of materials. The effect of system geometry was evaluated by considering planar, cylindrical, and spherical geometries. The numerical analysis was extended to the case of continuous cooling, for a range of cooling rates from 0.1 to 100 K/s. The results provide information on how quickly the system deviates from equilibrium during cooling, and what the final compositions and phase fractions are as a function of cooling rate. In most cases, the deviation from equilibrium, in terms of residual ferrite content and composition, increased as the cooling rate increased, as expected. However, under some conditions, it was found that the lowest cooling rates actually deviated further from equilibrium than intermediate cooling rates. This curious phenomenon was investigated in detail and was explained in terms of the indirect path toward final. Such indirect equilibration is often found during and typical of diffusion-controlled transformation behavior in multi-component systems.
Vitek, J.M.; Vitek, S.A.
Heat pipe radiation cooling (HPRC) for high-speed aircraft propulsion. Phase 2 (feasibility) final report
The National Aeronautics and Space Administration (NASA), Los Alamos National Laboratory (Los Alamos), and CCS Associates are conducting the Heat Pipe Radiation Cooling (HPRC) for High-Speed Aircraft Propulsion program to determine the advantages and demonstrate the feasibility of using high-temperature heat pipes to cool hypersonic engine components. This innovative approach involves using heat pipes to transport heat away from the combustor, nozzle, or inlet regions, and to reject it to the environment by thermal radiation from adjacent external surfaces. HPRC is viewed as an alternative (or complementary) cooling technique to the use of pumped cryogenic or endothermic fuels to provide regenerative fuel or air cooling of the hot surfaces. The HPRC program has been conducted through two phases, an applications phase and a feasibility phase. The applications program (Phase 1) included concept and assessment analyses using hypersonic engine data obtained from US engine company contacts. The applications phase culminated with planning for experimental verification of the HPRC concept to be pursued in a feasibility program. The feasibility program (Phase 2), recently completed and summarized in this report, involved both analytical and experimental studies.
Martin, R.A.; Merrigan, M.A.; Elder, M.G.; Sena, J.T.; Keddy, E.S. [Los Alamos National Lab., NM (United States); Silverstein, C.C. [CCS Associates, Bethel Park, PA (United States)
Research on two-phase flow instability in two parallel hollow conductors in the evaporating cooling generator
As a new generator cooling technology, the evaporative cooling technology has been researched on various aspects to a certain extent, such as the two-phase flow pressure drop, temperature distribution and etc. But there has no research reported on the two-phase flow instability in the parallel hollow conductors in the evaporative cooling system. The occurrence of two-phase flow instability phenomena can
Dong Haihong; Yu Shunzhou; Fu Deping; Gu Guobiao
Outer atmospheres of cool stars. XIII - Capella at critical phases
NASA Technical Reports Server (NTRS)
The results are presented of a program of high-dispersion spectroscopy of Capella at critical orbital phases utilizing the International Ultraviolet Explorer. The considered program had the objective to establish as carefully as possible the relative ultraviolet emission levels of the Capella primary and secondary in order to obtain an understanding regarding the nature of their chromospheres and coronae. The results of the program confirm the earlier study of the Capella by Ayres and Linsky (1980), which was limited to orbital phases 0.50 and 0.75. Both programs found that the Capella secondary is considerably brighter than the primary, in surface flux, in all of the prominent far-ultraviolet emissions, particularly the high-excitation CII-CIV lines. In addition, the present study has revealed several puzzling aspects of the system. It is concluded that the Capella primary is comparatively bright, for a yellow giant, in far-ultraviolet and perhaps also in soft X-ray normalized fluxes. The implications of this conclusion are evaluated.
Ayres, T. R.; Schiffer, F. H., III; Linsky, J. L.
District energy growth
Utility competition is heating up as utilities focus attention back to district energy after turning away from it for decades after World War II. Utilities are re-entering the district energy business by forming non-regulated district energy subsidiaries. Trigen Energy Corp., as the largest commercial owner and operator of community district energy systems in North America, defines the district heating and cooling (DHC) growth trend of systems being taken over, upgraded and expanded. These trends gather momentum with the economic attractions that have propelled DHC for the past decade and more. With DHC, a building owner worries less about maintenance and can operate with a smaller workforce for maintenance. Heating and cooling systems operate more reliably. Trigen`s Trenton plant, producing electricity, heating and cooling, recovers 66 percent of input energy - more than double the efficiency of conventional electric generation. Yet, it produces less than one-half the pollutants of conventional generation.
Seeley, R.S.
Phase-difference and spectroscopic imaging for monitoring of human brain temperature during cooling.
Decrease of the human brain temperature was induced by intranasal cooling. The main purpose of this study was to compare the two magnetic resonance methods for monitoring brain temperature changes during cooling: phase-difference and magnetic resonance spectroscopic imaging (MRSI) with high spatial resolution. Ten healthy volunteers were measured. Selective brain cooling was performed through nasal cavities using saline-cooled balloon catheters. MRSI was based on a radiofrequency spoiled gradient echo sequence. The spectral information was encoded by incrementing the echo time of the subsequent eight image records. Reconstructed voxel size was 1�1�5 mm(3). Relative brain temperature was computed from the positions of water spectral lines. Phase maps were obtained from the first image record of the MRSI sequence. Mild hypothermia was achieved in 15-20 min. Mean brain temperature reduction varied in the interval <-3.0; -0.6>�C and <-2.7; -0.7>�C as measured by the MRSI and phase-difference methods, respectively. Very good correlation was found in all locations between the temperatures measured by both techniques except in the frontal lobe. Measurements in the transversal slices were more robust to the movement artifacts than those in the sagittal planes. Good agreement was found between the MRSI and phase-difference techniques. PMID:22819582
Weis, Jan; Covaciu, Lucian; Rubertsson, Sten; Allers, Mats; Lunderquist, Anders; Ortiz-Nieto, Francisco; Ahlstr�m, H�kan
Gray-molasses cooling of 39K to a high phase-space density
We present new techniques in cooling 39K atoms using laser light close to the D1 transition. First, a new compressed-MOT configuration is taking advantage of gray-molasses-type cooling induced by blue-detuned D1 light. It yields an optimized density of atoms. Then, we use pure D1 gray molasses to further cool the atoms to an ultra-low temperature of 6\\ \\mu\\text{K} . The resulting phase-space density is 2\\times 10^{-4} and will ease future experiments with ultracold potassium. As an example, we use it to directly load up to 3\\times 10^7 atoms in a far detuned optical trap, a result that opens the way to the all-optical production of potassium degenerate gases.
Salomon, G.; Fouch�, L.; Wang, P.; Aspect, A.; Bouyer, P.; Bourdel, T.
Phase I, open-cycle absorption solar cooling. Part IV. Executive summary analysis and resolution of critical issues and recommendations for Phase II. Final report
The objective of this project is to advance lower cost solar cooling technology with the feasibility analysis, design and evaluation of proof-of-concept open cycle solar cooling concepts. The work is divided into three phases, with planned completion of each phase before proceeding with the following phase: Phase I - performance/economic/environmental related analysis and exploratory studies; Phase II - design and construction of an experimental system, including evaluative testing; Phase III - extended system testing during operation and engineering modifications as required. For Phase I, analysis and resolution of critical issues were completed with the objective of developing design specifications for an improved prototype OCA system.
Wood, B.D.
Active two phase cooling of optics. Final technical report, January 22, 1988--July 22, 1991
Two phase cooling of a higher powered laser optics offers a significant potential to advance the state-of-the-art in laser mirror cooling. Significant improvements can be achieved through the transfer of heat via working fluid phase change rather than specific heat capacity. These benefits include reduced jitter, and reduced electrical power consumption. In one actively pumped two phase cooling scheme, a saturated liquid is mechanically pumped into a porous metal layer under the mirror face where a fraction of the fluid is vaporized. The vapor-liquid mixture then leaves the face area and flows to a condenser. The condensate recirculates back to the mirror in a closed loop process. Because the working fluids have high latent heats of vaporization compared to their liquid heat capacities, a significant reduction in flow rate and pressure drop is possible. Analytical and experimental work has shown that a favorable combination of low distortion and low jitter is achievable with this approach. Also, since two phase heat transfer coefficients increase with increasing heat flux, a two phase cooled optic will achieve a lower distortion under non-uniform beam profiles. Jitter data were collected at absorbed heat fluxes up to 80 W/cm{sup 2} using a molybdenum demonstration mirror with methylamine coolant at 20{degrees}C. Low distortion coefficients were used as a design goal for this program at an absorbed heat flux up to 100 W/cm{sup 2}. A demonstration mirror was fabricated and tested for thermal/optical performance.Thermal performance levels in excess of 100 W/cm{sup 2} were demonstrated. Tests conducted at the TDTF showed thermal distortion coefficients at or below the design goal for absorbed heat fluxes up to levels in excess of 100 W/cm{sup 2}. No other cooling approach has been demonstrated that uses a low flow rate, low pressure drop cooling scheme, and demonstrates low jitter and low thermal distortion at absorbed heat fluxes near 100 W/cm{sup 2}.
Microwave frequency discriminator with a cooled sapphire resonator for ultra-low phase noise
First results are presented for an X-band frequency discriminator using a cooled sapphire microwave resonator. These results show a lower close-in (1-Hz-1-kHz offset) phase noise measurement floor than any oscillator presently available. This performance is made possible by a sapphire whispering-gallery mode resonator which shows the highest quality factor (with Q's up to 30 million) of any RF microwave, or
David G. Santiago; G. John Dick
Feasibility analysis of two-phase MHD energy conversion for liquid metal cooled reactors
A two-phase MHD energy conversion unit is proposed to a liquid metal cooled fast reactor. Using supercritical CO2 as the working fluid in the gas cycle without considering friction and heat losses, the optimized cycles efficiency is obtained, which is about 5% higher than that of the gas turbine Brayton cycle with the same regenerator\\/compressor configurations. Based on a simple
Qiao Wu; DuWayne L. Schubring; James J. Sienicki
Decay-phase Cooling and Inferred Heating of M- and X-class Solar Flares
Hydrodynamic modelling is a well established and important field in understanding the evolution of solar flares. However, in order to be of greatest use the results of such models must be compared to statistically significant samples of flare observations. In this talk we observationally investigate the hydrodynamic decay phase evolution of 72 M- and X-class flares using GOES/XRS, SDO/EVE and Hinode/XRT and quantify their cooling rates. The results are then compared to the predictions of an analytical zero-dimensional hydrodynamic model. We find that the model does not fit the observations well, but does provide a well-defined lower limit on a flare's total cooling time. The discrepancy between observations and the model is then assumed to be primarily due to heating during the decay phase. The decay-phase heating necessary to account for the discrepancy is quantified and found be ~50% of the total thermally radiated energy, as calculated with GOES/XRS. This suggests that the energy released during the decay phase may be as significant as that released during the rise phase.
Ryan, Daniel; Chamberlin, Phillip C.; Milligan, Ryan O.; Gallagher, Peter T
A self-regulating valve for single-phase liquid cooling of microelectronics
This paper reports on the design, optimization and testing of a self-regulating valve for single-phase liquid cooling of microelectronics. Its purpose is to maintain the integrated circuit (IC) at constant temperature and to reduce power consumption by diminishing flow generated by the pump as a function of the cooling requirements. It uses a thermopneumatic actuation principle that combines the advantages of zero power consumption and small size in combination with a high flow rate and low manufacturing costs. The valve actuation is provided by the thermal expansion of a liquid (actuation fluid) which, at the same time, actuates the valve and provides feed-back sensing. A maximum flow rate of 38 kg h-1 passes through the valve for a heat load up to 500 W. The valve is able to reduce the pumping power by up to 60% and it has the capability to maintain the IC at a more uniform temperature.
Donose, Radu; De Volder, Micha�l; Peirs, Jan; Reynaerts, Dominiek
Fast and sensitive method to determine chloroanisoles in cork using an internally cooled solid-phase microextraction fiber
A new generation of solid-phase microextraction (SPME) fiber, an internally cooled fiber (cold fiber with polydimethylsiloxane loading) that allows heating the sample matrix and simultaneously cooling the fiber coating, was used to determine 2,4-dichloroanisole, 2,6-dichloroanisole, 2,4,6-trichloroanisole and pentachloroanisole in cork. A comparison between the cold fiber and regular SPME fiber was performed. An automated headspace solid-phase microextraction (HS-SPME) using commercial
Eduardo Carasek; Erasmus Cudjoe; Janusz Pawliszyn
SOLERAS - Saudi University Solar Cooling Laboratories Project: King Abdulaziz University. Solar Cooling Systems Design Report. Phase 1 Report.
An assessment of the performance and adaptability of solar cooling systems to the Saudi Arabian environment was studied at King Abdulaziz University. Development of a solar research laboratory and the hardware and software available for installation are c...
Advanced phase change materials and systems for solar passive heating and cooling of residential buildings
During the last three years under the sponsorship of the DOE Solar Passive Division, the University of Dayton Research Institute (UDRI) has investigated four phase change material (PCM) systems for utility in thermal energy storage for solar passive heating and cooling applications. From this research on the basis of cost, performance, containment, and environmental acceptability, we have selected as our current and most promising series of candidate phase change materials, C-15 to C-24 linear crystalline alkyl hydrocarbons. The major part of the research during this contract period was directed toward the following three objectives. Find, test, and develop low-cost effective phase change materials (PCM) that melt and freeze sharply in the comfort temperature range of 73--77{degree}F for use in solar passive heating and cooling of buildings. Define practical materials and processes for fire retarding plasterboard/PCM building products. Develop cost-effective methods for incorporating PCM into building construction materials (concrete, plasterboard, etc.) which will lead to the commercial manufacture and sale of PCM-containing products resulting in significant energy conservation.
Salyer, I.O.; Sircar, A.K.; Dantiki, S.
Influence of Strain History and Cooling Rate on the Austenite Decomposition Behavior and Phase Transformation Products in a Microalloyed Steel
The effect of simple strain path changes as well as post-deformation continuous cooling rate during thermomechanical-controlled processing of microalloyed steel was studied using laboratory physical simulation. The phase transformation characteristics were directly analyzed by dilatometry under various cooling rates. The microstructures of the transformation products were characterized quantitatively using EBSD. The results have shown that while strain path changes impose a considerable influence on the hot flow behavior of the austenite, the cooling rate following hot deformation is the determining factor of the phase transformation mechanism and behavior which establishes the final transformation products and subsequent mechanical properties.
Sun, L.; Muszka, K.; Wynne, B. P.; Palmiere, E. J.
Phase 3 geophysical studies in the Wadi Bidah District, Kingdom of Saudi Arabia
USGS Publications Warehouse
Detailed geophysical measurements have been made in the Rabathan area, Wadi Bidah district, Kingdom of Saudi Arabia, at the site of diamond drill holes RAB-1, -2, and -3; these measurements suggest that the causative source for the anomalous EM (electromagnetic) and SP (self-potential) responses is probably highly conductive zones of Precambrian siliceous-carbonaceous rocks. Although many of the zones are no more than a few meters wide, they commonly contain 50 to 80 percent carbonaceous material and locally abundant pyrite. In places, several thin layers of highly concentrated carbonaceous material interlayered with chert form a multiple conductive zone that is seen in the geophysical data as complex anomaly patterns. In the geologic environment of Wadi Bidah, massive sulfide-bearing zones cannot be distinguished from siliceous-carbonaceous zones on the basis of the EM-SP responses. In North America in similar environments, complex resistivity methods used in experimental research have successfully discriminated between sulfide and carbonaceous conductors. Tests of such methods in the Wadi Bidah district are recommended. Geologic, geochemical, and geophysical data at the Jabal Mohr prospect suggest the possibility of mineralized rocks at depth over a possible strike length of 400 m.
Flanigan, V. J.; Sadek, Hamdy; Smith, C. W.
The impact of a phase-change cooling vest on heat strain and the effect of different cooling pack melting temperatures.
Cooling vests (CV) are often used to reduce heat strain. CVs have traditionally used ice as the coolant, although other phase-change materials (PCM) that melt at warmer temperatures have been used in an attempt to enhance cooling by avoiding vasoconstriction, which supposedly occurs when ice CVs are used. This study assessed the effectiveness of four CVs that melted at 0, 10, 20 and 30 �C (CV?, CV??, CV??, and CV??) when worn by 10 male volunteers exercising and then recovering in 40 �C air whilst wearing fire-fighting clothing. When compared with a non-cooling control condition (CON), only the CV? and CV?? vests provided cooling during exercise (40 and 29 W, respectively), whereas all CVs provided cooling during resting recovery (CV? 69 W, CV?? 66 W, CV?? 55 W and CV?? 29 W) (P < 0.05). In all conditions, skin blood flow increased when exercising and reduced during recovery, but was lower in the CV? and CV?? conditions compared with control during exercise (observed power 0.709) (P < 0.05), but not during resting recovery (observed power only 0.55). The participants preferred the CV?? to the CV?, which caused temporary erythema to underlying skin, although this resolved overnight after each occurrence. Consequently, a cooling vest melting at 10 �C would seem to be the most appropriate choice for cooling during combined work and rest periods, although possibly an ice-vest (CV?) may also be appropriate if more insulation was worn between the cooling packs and the skin than used in this study. PMID:23160652
House, James R; Lunt, Heather C; Taylor, Rowan; Milligan, Gemma; Lyons, Jason A; House, Carol M
A study of the cool gas in the Large Magellanic Cloud. I. Properties of the cool atomic phase - a third H i absorption survey
The cool atomic interstellar medium of the Large Magellanic Cloud (LMC) seems to be quite different from that in the Milky Way. In a series of three papers we study the properties of the cool atomic hydrogen in the LMC (Paper I), its relation to molecular clouds using SEST-CO-observations (Paper II) and the cooling mechanism of the atomic gas based on ISO-[\\CII]-investigations (Paper III). In this paper we present the results of a third 21 cm absorption line survey toward the LMC carried out with the Australia Telescope Compact Array (ATCA). 20 compact continuum sources, which are mainly in the direction of the supergiant shell LMC 4, toward the surroundings of 30 Doradus and toward the eastern steep \\HI\\ boundary, have been chosen from the 1.4 GHz snapshot continuum survey of Marx et al. We have identified 20 absorption features toward nine of the 20 sources. The properties of the cool \\HI\\ clouds are investigated and are compared for the different regions of the LMC taking the results of Dickey et al. (survey 2) into account. We find that the cool \\HI\\ gas in the LMC is either unusually abundant compared to the cool atomic phase of the Milky Way or the gas is clearly colder (\\Tc\\ ~ 30 K) than that in our Galaxy (\\Tc\\ ~ 60 K). The properties of atomic clouds toward 30 Doradus and LMC 4 suggest a higher cooling rate in these regions compared to other parts of the LMC, probably due to an enhanced pressure near the shock fronts of LMC 4 and 30 Doradus. The detected cool atomic gas toward the eastern steep \\HI\\ boundary might be the result of a high compression of gas at the leading edge. The Australia Telescope is funded by the Commonwealth of Australia for operation as a National Facility managed by CSIRO.
Marx-Zimmer, M.; Herbstmeier, U.; Dickey, J. M.; Zimmer, F.; Staveley-Smith, L.; Mebold, U.
Fundamental study for a working mechanism of Phase Adjuster set on thermoacoustic cooling system
Thermoacoustic cooling systems are drawing attention as next-generation eco-systems that can reuse and transform unused energy such as exhaust energy and solar energy. For the practical use of such systems, improvement of heat-sound energy conversion efficiency remains as an important challenge. We proposed a Phase Adjuster as a device for improving energy conversion efficiency However, the mechanism for that improvement remains unclear. Herein, to ascertain the reason, a parameter prediction method for determining the acoustic field was investigated by dividing the system into two parts: a Prime Mover (PM) part and a Phase Adjuster (PA) part. Consequently, the acoustic impedance cross-point of the PM part and the PA part on a complex plane is expected to represent a resonance frequency and a steady-state temperature ratio of the self-excited oscillation system.
Sahashi, Kazuki; Sakamoto, Shin-ichi; Watanabe, Yoshiaki
Prediction of Continuous Cooling Transformation Diagrams for Dual-Phase Steels from the Intercritical Region
The purpose of the present work is the implementation and validation of a model able to predict the microstructure changes and the mechanical properties in the modern high-strength dual-phase steels after the continuous annealing process line (CAPL) and galvanizing (Galv) process. Experimental continuous cooling transformation (CCT) diagrams for 13 differently alloying dual-phase steels were measured by dilatometry from the intercritical range and were used to tune the parameters of the microstructural prediction module of the model. Mechanical properties and microstructural features were measured for more than 400 dual-phase steels simulating the CAPL and Galv industrial process, and the results were used to construct the mechanical model that predicts mechanical properties from microstructural features, chemistry, and process parameters. The model was validated and proved its efficiency in reproducing the transformation kinetic and mechanical properties of dual-phase steels produced by typical industrial process. Although it is limited to the dual-phase grades and chemical compositions explored, this model will constitute a useful tool for the steel industry.
Colla, V.; Desanctis, M.; Dimatteo, A.; Lovicu, G.; Valentini, R.
The partitioning of copper among selected phases of geologic media of two porphyry copper districts, Puerto Rico
In experiments designed to determine the manner in which copper is partitioned among selected phases that constitute geologic media, we have applied the five-step sequential extraction procedure of Chao and Theobald to the analysis of drill core, soils, and stream sediments of the Rio Vivi and Rio Tanama porphyry copper districts of Puerto Rico. The extraction procedure affords a convenient means of determining the trace-metal content of the following fractions: (1) Mn oxides and "reactive" Fe oxides; (2) "amorphous" Fe oxides; (3) "crystalline" Fe oxides; (4) sulfides and magnetite; and (5) silicates. An additional extraction between steps (1) and (2) was performed to determine organic-related copper in stream sediments. The experimental results indicate that apportionment of copper among phases constituting geologic media is a function of geochemical environment. Distinctive partitioning patterns were derived from the analysis of drill core from each of three geochemical zones: (a) the supergene zone of oxidation; (b) the supergene zone of enrichment; and (c) the hypogene zone; and similarly, from the analysis of; (d) soils on a weakly leached capping; (e) soils on a strongly leached capping; and (f) active stream sediment. The experimental results also show that geochemical contrasts (anomaly-to-background ratios) vary widely among the five fractions of each sampling medium investigated, and that at least one fraction of each medium provides substantially stronger contrast than does the bulk medium. Fraction (1) provides optimal contrast for stream sediments of the district; fraction (2) provides optimal contrast for soils on a weakly leached capping; fraction (3) provides optimal contrast for soils on a strongly leached capping. Selective extraction procedures appear to have important applications to the orientation and interpretive stages of geochemical exploration. Further investigation and testing of a similar nature are recommended. ?? 1981.
Learned, R. E.; Chao, T. T.; Sanzolone, R. F.
SOLERAS - Saudi University Solar Cooling Laboratories Project: King Abdulaziz University. Solar cooling systems design report. Phase 1 report
An assessment of the performance and adaptability of solar cooling systems to the Saudi Arabian environment was studied at King Abdulaziz University. Development of a solar research laboratory and the hardware and software available for installation are considered. The university's facilities for solar energy research are briefly described. A budget for the research project is proposed. (BCS)
Solar Heating and Cooling of Buildings. Phase O. Feasibility and Planning Study. Final Report. Volume I, Executive Summary.
Work performed in the first step (Phase O) of a program to assess the feasibility and merits of the use of solar energy for heating and cooling buildings and providing hot water is summarized. In Phase O the technical, economic, societal, legal, and envir...
Collaborating To Serve Arizona Students & Families More Effectively: Phase 1 Report. Evaluation of Murphy School District-Department of Economic Security Collaborative Project.
This report presents the results of Phase I of an evaluation of the Murphy School District (MSD)-Department of Economic Security (DES) collaborative effort, one of the first interagency partnerships in the state of Arizona that attempts to address the needs of students and their families more effectively. The primary purposes of the evaluation are�
Izu, Jo Ann; Carreon, Tori
Effects of deep cryogenic treatment on the solid-state phase transformation of Cu�Al alloy in cooling process
The solid-state phase transformation temperature and duration of deep cryogenic treated and untreated Cu�Al alloys in cooling process were measured by differential scanning calorimetry measurement. The solid-state phase transformation activation energy and Avrami exponent were calculated according to these measurements. The effects of deep cryogenic treatment on the solid-state phase transformation were investigated based on the measurement and calculation as
Yuhui Wang; Bo Liao; Jianhua Liu; Shuqing Chen; Yu Feng; Yanyan Zhang; Ruijun Zhang
The influence of different cooling processes on phase, microstructure, and magnetocaloric properties of LaFe11.6Si1.4 compounds
The LaFe11.6Si1.4 compounds are annealed at 1503 K for 5 h and cooled down to room temperature by furnace cooling, air cooling, and quenching in ice water, respectively. The main phase is 1:13 phase in those compounds. The impurity phase is ?-Fe, and the amount of LaFeSi phase is so small that it is hard to be observed in their XRD patterns. 1:13 phase has a precipitation reaction at 1308 K during cooling process and produces LaFeSi phase. But the cooling rate in the high temperature range is very high and the time kept at about 1308 K is very short, also the amount of LaFeSi phase reformed during cooling process is very small. It results in there being almost no difference in XRD patterns and SEM micrographs of LaFe11.6Si1.4 compounds annealed at 1503 K (5 h) and followed by furnace cooling, air cooling, and quenching in ice water to room temperature respectively. For studying the influence of different cooling processes on magnetic property, the TC, thermal and magnetic hysteresis, magnetocaloric effect, and relative cooling power of those compounds are investigated. The result shows that the maximum ?SM (T, H) and RCP of LaFe11.6Si1.4 prepared by furnace cooling is not smaller than the other two alloys under the field of 0-2 T.
Chen, Xiang; Chen, Yungui; Tang, Yongbo
Brazing of the Tore Supra actively-cooled Phase III limiter*1
The head of the water-cooled Tore Supra Phase III Limiter is a bank of 14 round OFHC copper tubes, curved to fit the plasma radius, onto which several hundred pyrolytic graphite (PG) tiles and a lesser number of carbon fiber composite tiles are brazed. The small allowable tolerances for fitting the tiles to the tubes and mating of compound curvatures made the brazing and fabrication extremely challenging. The paper describes the fabrication process with emphasis on the procedure for brazing. In the fixturing for vacuum furnace brazing, the tiles were each independently clamped to the tube with an elaborate set of "window frame" clamps. Braze quality was evaluated with transient heating tests. Some rebrazing was necessary.
Nygren, R. E.; Walker, C. A.; Lutz, T. J.; Hosking, F. M.; McGrath, R. T.
District Heating and Cooling Systems for Communities Through Power Plant Retrofit and Distribution Network. Final Report of the City of Piqua, Ohio. Executive Summary.
This summary of the City of Piqua's District Heating efforts presents the salient points detailed in the city's 528 page final report and the accompanying appendices submitted to the Department of Energy. The final report consists of the following: introd...
District Heating and Cooling Systems for Communities Through Power Plant Retrofit and Distribution Network. Final Report of the City of Piqua, Ohio.
The following are reported: thermal and electrical load analysis, alternative service areas, power plant analysis and thermal supply options, technical district heating development branch, air quality impact analysis, institutional considerations and eval...
Experimental Study on Closed-Loop Two-Phase Thermosyphon Devices for Cooling MCMs
Thermosyphon cooling modules, to cool multichip modules (MCMs), were designed and tested. The cooling module consists of a cold plate with microfinned channels and a plate-type integrated condenser. A separate flow model was employed to predict the mass flux and the pressure drop in the channel of the cold plate. The local and average convective boiling heat transfer coefficients and
Effective cooling of gas turbine combustor liners, combustor transition pieces, turbine vanes (nozzles) and blades (buckets) is a critical task to protect these components from the flue gas at extremely high temperature. Air film cooling has been successfully used to cool these hot sections for the last half century. However, the net benefits from the traditional methods seem to be
Xianchang Li; Ting Wang
Air-cycle cooling of electric power cables: Phase I. Final report
A study was conducted to determine the feasibility of using an air cycle system for cooling underground electrical power transmission cables. The air cycle system features an expansion turbine where ambient air is expanded to subatmospheric pressure; this air is circulated in a plate fin heat exchanger and cools the cable dielectric oil. The cooling capacity of the low pressure
Active (air-cooled) vs. passive (phase change material) thermal management of high power lithium-ion packs: Limitation of temperature rise and uniformity of temperature distribution
The effectiveness of passive cooling by phase change materials (PCM) is compared with that of active (forced air) cooling. Numerical simulations were performed at different discharge rates, operating temperatures and ambient temperatures of a compact Li-ion battery pack suitable for plug-in hybrid electric vehicle (PHEV) propulsion. The results were also compared with experimental results. The PCM cooling mode uses a
Rami Sabbah; R. Kizilel; J. R. Selman; S. Al-Hallaj
Cooling-rate dependent vortex structure in Rb 3C 60. Vortex-glass phase in a quenched sample
Magnetic flux vortex-induced electron paramagnetic resonance (EPR) line-width broadening in a Rb 3C 60 powder sample has been studied between 7 and 40 K by the X-band (?9 GHz and an applied magnetic field of 320 mT for g=2 signals) EPR spectroscopy. A striking difference in the temperature dependence of the vortex-induced line-width broadening exists between the slowly and rapidly cooled sample. These two classes of behaviour strongly indicate the formation of different vortex states depending on the cooling rate. It is suggested that a vortex-liquid/vortex-glass phase transition occured in the quenched (rapid cooling) sample at ?18 K. It was found that the EPR line-width is independent of temperature in the vortex-glass phase.
Wang, D. M.; Bramley, R.; Dinse, K.-P.
The kinetics of the austenite�ferrite phase transformation of Fe-Mn: differential thermal analysis during cooling
Differential thermal analysis (DTA) has been employed to study the austenite�ferrite phase transformation of Fe-1.89at% Mn upon cooling. The transformation has been shown to occur in two stages. The first stage is not thermally activated; the second stage is thermally activated. A phase transformation model, incorporating a new impingement correction, has been used for the extraction, from the DTA experiments,
A. T. W. Kempen; F. Sommer; E. J. Mittemeijer
Thermal analysis of n-alkane phase change material mixtures. Progress report, January 1, 1991--March 31, 1991.
Tests were performed to characterize the thermal behavior of it number of n-alkanes to be used as phase change materials (PCMs) in district cooling applications. Hexadecane and tetradecane were mixed in different fractions, and their thermal behavior was ...
Y. I. Chio E. Choi H. G. Lorsch
Cooling vests with phase change materials: the effects of melting temperature on heat strain alleviation in an extremely hot environment.
A previous study by the authors using a heated thermal manikin showed that the cooling rates of phase change material (PCM) are dependent on temperature gradient, mass, and covering area. The objective of this study was to investigate if the cooling effects of the temperature gradient observed on a thermal manikin could be validated on human subjects in extreme heat. The subjects wore cooling vests with PCMs at two melting temperatures (24 and 28�C) and fire-fighting clothing and equipment, thus forming three test groups (vest24, vest28 and control group without the vest). They walked on a treadmill at a speed of 5 km/h in a climatic chamber (air temperature = 55�C, relative humidity = 30%, vapour pressure = 4,725 Pa, and air velocity = 0.4 m/s). The results showed that the PCM vest with a lower melting temperature (24�C) has a stronger cooling effect on the torso and mean skin temperatures than that with a higher melting temperature (28�C). Both PCM vests mitigate peak core temperature increase during the resting recovery period. The two PCM vests tested, however, had no significant effect on the alleviation of core temperature increase during exercise in the heat. To study the possibility of effective cooling of core temperature, cooling garments with PCMs at even lower melting temperatures (e.g. 15�C) and a larger covering area should be investigated. PMID:21127896
Gao, Chuansi; Kuklane, Kalev; Holm�r, Ingvar
High Resolution Infrared Spectroscopy of Jet-Cooled Phenyl Radical in the Gas Phase
Phenyl radical (C_6H_5) is one of the most important reactive intermediates, as it is formed from the homolytic cleavage of a CH bond in benzene (C_6H_6), and hence it plays a central role in the combustion of fossil fuels that are typically rich in aromatics. We recently recorded the first high resolution infrared spectra of jet-cooled phenyl radical in the gas phase. This was obtained by direct absorption laser spectroscopy in a slit-jet discharge supersonic expansion of a phenyl halide precursor (C_6H_5X, i.e. C_6H_5I and C_6H_5Br) diluted in a Neon/Helium gas mixture. We observed an A-type band, which arises from a fundamental excitation of the out-of-phase symmetric CH stretch (?_{19}). The unambiguous assignment of the rotational structure in this band to C_6H_5 is facilitated by comparing 2-line combination differences with the Fourier transform microwave (FTM) and direct absorption millimeter-wave (mm-wave) measurements of the ground state by McMahon et al. A least-squares fit to an asymmetric top Hamiltonian of the rotationally-resolved vibrational band is done to determine upper-state rotational constants and a gas-phase band origin (?_0) of 3071.8904 (10) cm^{-1}. This is in very good agreement with the value of 3071 cm^{-1} for the out-of-phase symmetric CH stretch of phenyl reported by Friderichsen et al. from matrix isolation studies, which indicates a surprisingly small red shift due to the low-temperature argon environment. R. J. McMahon, M. C. McCarthy, C. A. Gottlieb, J. B. Dudek, J. F. Stanton and P. Thaddeus, Ap. J. 590, L61 (2003). A. V. Friderichsen, J. G. Radziszewski, M. R. Nimlos, P. R. Winter, D. C. Dayton, D. E. David and G. B. Ellison, J. Am. Chem. Soc. 123, 1977 (2001).
Sharp-Williams, Erin N.; Roberts, Melanie A.; Nesbitt, David J.
Modeling Single-Phase and Boiling Liquid Jet Impingement Cooling in Power Electronics.
Jet impingement has been an attractive cooling option in a number of industries over the past few decades. Over the past 15 years, jet impingement has been explored as a cooling option in microelectronics. Recently, interest has been expressed by the auto...
S. V. Narumanchi V. Hassani D. Bharathan
Solar Heating and Cooling of Buildings: Phase 0. Executive Summary. Final Report.
After the Westinghouse Electric Corporation made a comprehensive analysis of the technical, economic, social, environmental, and institutional factors affecting the feasibility of utilizing solar energy for heating and cooling buildings, it determined that solar heating and cooling systems can become competitive in most regions of the country in�
Westinghouse Electric Corp., Baltimore, MD.
Fate of arsenic-bearing phases during the suspended transport in a gold mining district (Isle river Basin, France).
Arsenic-rich (~140-1520 mg x kg(-1)) suspended particulate matter (SPM) was collected daily with an automatic sampler in the Upper Isle River (France) draining a former gold mining district in order to better understand the fate of arsenic during the suspended transport (particles smaller than 50 ?m). Various techniques at a micrometric scale (EPMA, quantitative SEM-EDS with an automated particle counting including classification system and ?XRD) were used to directly characterize As-bearing phases. The most frequent ones were aggregates of fine clay particles. Their mineralogy varied with particle sources involved. These aggregates were formed by chlorite-phlogopite-kaolinite assemblages during the high flow and chlorite-illite-montmorillonite during the low flow. Among all the observed As-carriers in SPM, these clay assemblages were the least As-rich (0.10 up to 1.58 wt.% As) and their median As concentrations suggested that they were less concentrated during the high flow than during the low flow. Iron oxyhydroxides were evidenced by ?XRD in these clay aggregates, either as micro- to nano-sized particles and/or as coating. (Mn, Fe)oxyhydroxides were also present as discrete particles. Manganese oxides (0.14-1.26 wt.% As) transport significantly more arsenic during the low flow than during the high flow (0.16-0.79 wt.% As). The occurrence of Fe oxyhydroxide particles appeared more complex. During the low flow, observations on banks and in wetlands of freshly precipitated Fe hydroxides (ferrihydrite-type) presented the highest As concentrations (up to 6.5 wt.% As) but they were barely detected in SPM at a microscale. During the high flow, As-rich Fe-oxyhydroxides (0.10-2.80 wt.% As) were more frequent, reflecting mechanical erosion and transport when the surface water level increased. Arsenic transfers from SPM to corresponding aqueous fraction mostly depend on As-carrier stability. This study shows the temporal occurrence of each type of As-bearing phases in SPM, their As concentrations at a particle scale and abundance according to hydrological periods. PMID:21925708
Grosbois, C; Courtin-Nomade, A; Robin, E; Bril, H; Tamura, N; Sch�fer, J; Blanc, G
Computational method for generalized analysis of pumped two-phase cooling systems and its application to a system used in data-center environments
Two-phase pumped-loop systems are being actively considered for cooling of high heat load electronics. In the present study, a computational method based on a two-level approach is developed for generalized system-level analysis of two-phase pumped-loop cooling systems containing multiple branches under steady-state conditions. Detailed one-dimensional analysis of components with distributed two-phase flow is performed to determine their flow and thermal
Kanchan M. Kelkar; Suhas V. Patankar; Sukhvinder S. Kang; M. Iyengar; R. R. Schmidt
Jet-cooled and room temperature FTIR spectra of the dimer of formic acid in the gas phase
Room temperature absorption spectra of the gaseous (C2h) dimer of formic acid were recorded from the lowest energy fundamental, ?16, with origin at 69.2 cm?1, up to the CH overtone bands with ?v=4, with origin at 11,103 cm?1, using a high resolution Fourier transform interferometer. These spectra are complemented with liquid phase data in the NIR region. In addition, jet-cooled
R. Georges; M. Freytes; D. Hurtmans; I. Kleiner; J. Vander Auwera; M. Herman
In vivo MRI using liquid nitrogen cooled phased array coil at 3.0 T
PubMed Central
A liquid nitrogen (LN2) cooled dual-channel array coil was designed and built for use on a 3.0-T whole-body scanner. In vivo imaging of a volunteer's fingers and imaging of a deceased mouse and oil phantom were performed using the LN2 cooled array and a similar room-temperature coil. Imaging results showed that the LN2 cooled array provides a signal-to-noise ratio gain of up to 240% as compared with its room-temperature counterpart. LN2 cooled arrays may be useful for high-resolution clinical imaging of joints, skin, eyes and peripheral vessels as well as for biomedical imaging of small animals in human disease modeling.
Kwok, Wingchi E.; You, Zhigang
User manual for GEOCITY: A computer model for cost analysis of geothermal district-heating-and-cooling systems. Volume 1: Main text
The cost of residential space heating, space cooling, and sanitary water heating or process heating (cooling) using geothermal energy from a hydrothermal reservoir was calculated. The GEOCITY simulates the complete geothermal heating and cooling system, which consists of two principal parts: the reservoir and fluid transmission system and the distribution system. Geothermal space heating is provided by circulating hot water through radiators, convectors, and fan-coil units. Geothermal process heating is provided by directly using the hot water or by circulating it through a process heat exchanger. The life cycle cost of thermal energy from the reservoir and fluid transmission system to the distribution system and the life cycle cost of heat (chill) to the end users are calculated by discounted cash flow analysis.
Huber, H. D.; Fassbender, L. L.; Bloomster, C. H.
Streamflow changes in Alaska between the cool phase (1947-1976) and the warm phase (1977-2006) of the Pacific Decadal Oscillation: The influence of glaciers
Streamflow data from 35 stations in and near Alaska were analyzed for changes between the cool phase (1947-1976) and the warm phase (1977-2006) of the Pacific Decadal Oscillation. Winter, spring, and summer flow changes and maximum annual flow changes were different for glaciated basins (more than 10% glacier-covered area) than for nonglaciated basins, showing the influence of glaciers on historical streamflowchanges. Mean February flows, for example, increased for the median of available stations by 45% for glaciated basins and by 17% for nonglaciated ones.
Hodgkins, Glenn A.
36 CFR 28.3 - Boundaries: The Community Development District; The Dune District; The Seashore District.
Code of Federal Regulations, 2010 CFR
...The Community Development District; The Dune District; The Seashore District. 28...The Community Development District; The Dune District; The Seashore District. ...District, the Seashore District, and the Dune District. (b) The Community...
Lattice constant, bandgap, thickness, and surface morphology of InGaAsP-InP layers grown by step-cooling, equilibrium-cooling, supercooling and two-phase-solution growth techniques
Constant composition InGaAsP epitaxial layers can be grown on (100) InP substrates at a constant temperature using the diffusion-limited step-cooling growth technique, and in general, compositionally graded layers result when the diffusion-limited equilibrium-cooling, supercooling, and two-phase-solution growth techniques are used. The lattice constant and energy gap of the epitaxial layers grown using the step-cooling technique are nearly independent of small variations of X{p/l} and the amount of step cooling, but are dependent on growth temperature. The dependence of lattice constant and energy gap of the epitaxial layers on X{Ga/l} and X{As/l} has been determined for the step-cooling and supercool ing techniques.
Feng, M.; Cook, L. W.; Tashima, M. M.; Stillman, G. E.
Simulation aided design of a two-phase thermosyphon for power electronics cooling
In this paper we present a novel system for power electronics cooling consisting of a thermosyphon loop composed of an evaporator, to which the power modules are attached, and of a condenser, formed by a set of vertically mounted aluminum panels. To facilitate the optimization of the design of the condenser, which is critical for the whole system performance, we
Francesco Agostini; Thomas Gradinger; Carlo de Falco
This report documents the Savannah River National Laboratory (SRNL) support for the Tank Closure and Technology Development (TCTD) group's strategy for closing high level radioactive waste (HLW) tanks at the Savannah River Site (SRS). Specifically, this task addresses the ability to successfully fill intact cooling coils, presently within the HLW tanks, with grout that satisfies the fresh and cured grout
E Hansen; A Alex Cozzi
Modelling the rapid cooling and casting of chocolate to predict phase behaviour
In recent years, rapid cooling processes have been developed to manufacture complex, three-dimensional shapes for confectionery products (e.g. chocolate Easter eggs). These processes are similar to injection moulding and casting processes used in the metallurgic and polymer industries. Although these manufacturing routes are commonly used, they are still poorly understood and thus not optimised. In traditional chocolate processing, cocoa butter
B. J. D. Le R�v�rend; I. Smart; P. J. Fryer; S. Bakalis
SBIR Phase II Project, ParSEC - Parallel Simulation of Electron Cooling.
The Department of Energy has plans, during the next two or three years, to design an electron cooling section for the collider ring at RHIC (Relativistic Heavy Ion Collider). Located at Brookhaven National Laboratory (BNL), RHIC is the premier nuclear phy...
D. Bruhwiler
Legionnaires' Disease Bacterium in power-plant cooling systems: Phase 1. Final report
A survey was undertaken of the distribution, density, viability, and infectivity of Legionnaires' Disease Bacteria (Legionella) in power plant cooling systems. Water samples were collected during each of the four seasons at various locations within each of nine power plants and from ambient waters at each site. Measurements of a number of physical and chemical characteristics were made, and Legionella
S. W. Christensen; J. A. Solomon; S. B. Gough; R. L. Tyndall; C. B. Fliermans
Alaska Regional Energy Resources Planning Project. Phase 2: coal, hydroelectric and energy alternatives. Volume I. Beluga Coal District Analysis
This volume deals with the problems and procedures inherent in the development of the Beluga Coal District. Socio-economic implications of the development and management alternatives are discussed. A review of permits and approvals necessary for the initial development of Beluga Coal Field is presented. Major land tenure issues in the Beluga Coal District as well as existing transportation routes and proposed routes and sites are discussed. The various coal technologies which might be employed at Beluga are described. Transportation options and associated costs of transporting coal from the mine site area to a connecting point with a major, longer distance transportation made and of transporting coal both within and outside (exportation) the state are discussed. Some environmental issues involved in the development of the Beluga Coal Field are presented. (DMC)
Rutledge, G.; Lane, D.; Edblom, G.
Variable Gravity Effects on the Cooling Performance of a Single Phase Confined Spray
The objective of this paper is to discuss the testing of a spray cooling experiment designed to be flown on NASA's KC-135 Reduced Gravity Testing Platform. Spray cooling is an example of a thermal management technique that may be utilized in high flux heat acquisition and high thermal energy transport concepts. Many researchers have investigated the utility of spray cooling for the thermal management of devices generating high heat fluxes. However, there has been little research addressing the physics and ultimate performance of spray cooling in a variable gravity environment. An experimental package, consisting of a spray chamber coupled to a fluid delivery loop system, was fabricated for variable gravity flight tests. The spray chamber contains two opposing nozzles spraying on target Indium Tin Oxide (ITO) heaters. These heaters are mounted on glass pedestals, which are part of a sump system to remove unconstrained liquid from the test chamber. Liquid is collected in the sumps and returned to the fluid delivery loop. Thermocouples mounted in and around the pedestals are used to determine both the heat loss through the underside of the IT0 heater and the heat extracted by the spray. A series of flight tests were carried out aboard the KC-135, utilizing the ability of the aircraft to produce various gravity conditions. During the flight tests, for a fixed flow rate, heat input was varied at 20, 30, 50, and 80W with variable gravities of 0.01, 0.16, 0.36, and 1.8g. Flight test data was compared to terrestrial baseline data in addition to analytical and numerical solutions to evaluate the heat transfer in the heater and support structure . There were significant differences observed in the spray cooling performance as a result of variable gravity conditions and heat inputs. In general, the Nussult number at the heater surface was found to increase with decreasing gravity conditions for heat loads greater than 30W.
Michalak, Travis; Yerkes, Kirk; Baysinger, Karri; McQuillen, John
Symbiotic halo star LT Del: Phase variations of the emission spectrum and parameters of the cool component
Long-term photometric and spectroscopic observations of the yellow symbiotic star LT Del are analyzed. UBV light curves are presented. Based on the observations of 20 cycles, we have refined the orbital period of the star, P = 476{�/d}0 � 1{�/d}0. The brightness has been found to be unstable at some orbital phases with an amplitude up to 0{�/ m } 3. We have measured the fluxes in hydrogen and helium emission lines and in continuum and investigated their relationship to the orbital period. The fluxes in hydrogen and HeI lines follow the UBV light curves in phase; the He II 4686 � flux does not depend on the phase and is constant within the accuracy of our measurements. The intensity ratio of the 4686 � andH ? lines changes from 0.2 to 0.9 over the period. We interpret the spectroscopic observations based on the hypothesis of heating and ionization of the stellar wind from a cool component by high-frequency radiation from a hot star with a temperature of 105 K. We have estimated the spectral type of the cool star from our photometry and its continuum energy distribution as a bright K2-4 red giant branch halo star. The bolometric luminosity and mass loss rate have been estimated for the K component to be L bol � 700 L ? and dot{M} � 10-8 M ? yr-1, respectively.
Arkhipova, V. P.; Esipov, V. F.; Ikonnikova, N. P.; Komissarova, G. V.; Noskova, R. I.
Analysis of the solar powered/fuel assisted Rankine cycle cooling system. Phase I. Revision
The subject of this analysis is a solar cooling system which consists of a conventional open-compressor chiller, driven by a novel hybrid steam Rankine cycle. Steam is generated by the use of solar energy collected at about 100/sup 0/C, and it is then superheated to about 600/sup 0/C in a fossil-fuel fired superheater. The steam drives a novel counter-rotating turbine, some of the heat from it is regenerated, and it is then condensed. Thermal storage is implemented as an integral part of the cycle, by means of hot-water which is flashed to steam when needed for driving the turbine. For the solar energy input, both evacuated and double-glazed flat-plate collectors were considered. A comprehensive computer program was developed to analyze the operation and performance of the entire power/cooling system. Each component was described by a separate subroutine to compute its performance from basic principles, and special attention was given to the parasitic losses, including pumps, fans and pressure drops in the piping and heat exchangers, and to describe the off-design performance of the components. The thermophysical properties of the fluids used are also described in separate subroutines. Transient simulation of the entire system was performed on an hourly basis over a cooling season in two representative climatic regions (Washington, DC, and Phoenix, AZ) for a number of system configurations.
Lior, N.; Koai, K.; Yeh, H.
Innovation District
NSDL National Science Digital Library
Many cities are working to create innovation districts in the vein of the Silicon Valley and it can be an up-hill battle. Boston is currently working just such a district in its Seaport neighborhood and has been the recent subject of many articles, blog posts, and general discussion. As the city's official website for the district, visitors to this site can learn about physical headquarters in the District Hall building, along with details on long-term strategy, and upcoming events. Some recent posts deal with co-working spaces, networking, and more. In the Resources area visitors can learn about the various innovative businesses that are already in the neighborhood, along with others in and around Boston.
Fast and sensitive method to determine chloroanisoles in cork using an internally cooled solid-phase microextraction fiber.
A new generation of solid-phase microextraction (SPME) fiber, an internally cooled fiber (cold fiber with polydimethylsiloxane loading) that allows heating the sample matrix and simultaneously cooling the fiber coating, was used to determine 2,4-dichloroanisole, 2,6-dichloroanisole, 2,4,6-trichloroanisole and pentachloroanisole in cork. A comparison between the cold fiber and regular SPME fiber was performed. An automated headspace solid-phase microextraction (HS-SPME) using commercial fibers and an internally cooled SPME fiber (CF-HS-SPME) coupled to gas chromatography-time-of-flight mass spectrometry (GC-TOF-MS) was used. The extraction conditions for both CF-HS-SPME and HS-SPME were optimized using full factorial design and Doehlert matrix. The best extraction conditions for CF-HS-SPME were obtained using 10 min of incubation time, 10 min of extraction time, and sample and fiber temperature of 130 and 10 degrees C, respectively. For HS-SPME, polydimethylsiloxane/divinylbenzene (PDMS/DVB) fiber was used with 10 min of incubation time, 75 min of extraction time, 85 degrees C of sample temperature, 8 ml of water was added and agitated at 500 rpm. The quantification limits for the target compounds using CF-HS-SPME procedure were between 0.8 and 1.6 ng g(-1) of cork, while for HS-SPME were between 4 and 6 ng g(-1) of cork. Furthermore, the CF-HS-SPME procedure could be used as a non-destructive method after minor modification of the agitator for the autosampler. PMID:17134712
Carasek, Eduardo; Cudjoe, Erasmus; Pawliszyn, Janusz
Electrical conductivity and phase composition of calcium aluminate cement containing air-cooled and water-cooled slag at 20, 40 and 60 �C
Calcium aluminate cement (CAC) pastes containing Egyptian air-cooled slag (AS) or water-cooled slag (WS) were prepared using different amounts of slag, namely, 5, 10, 15, 20 and 25 mass%. The pastes were prepared with deionized water using the required water of standard consistency to produce normal workability. The variations of electrical conductivity with the hydration time were measured at 20,
M. Heikal; M. S. Morsy; M. M. Radwan
Cooling Characteristics and Shape Memory Effects of R-Phase NiTi Alloys.
Numerical and experimental studies are carried out to characterize the response time and shape memory effects of an R-Phase NiTi alloy. The results of the numerical analysis indicate that the response speed of the R-Phase alloy can be four to six times fa...
Y. Q. Liu Z. J. Pu K. H. Wu
Cooling field dependence of exchange bias in phase-separated La0.88Sr0.12CoO3
We report the observation of exchange bias phenomena in the hole-doped perovskite cobaltite La0.88Sr0.12CoO3 in which a spontaneous phase separation occurs. When the sample is cooled in a static magnetic field through a freezing temperature, the magnetization hysteresis loops shift to the negative field. Moreover, the exchange bias strongly depends on the cooling field. These results highlight the important role of a glassy interface between the intrinsic inhomogeneous phases in a phase-separated system.
Tang, Yan-Kun; Sun, Young; Cheng, Zhao-Hua
Modeling phase transformations in ternary systems: Ferrite dissolution during continuous cooling.
The diffusion-controlled phase dissolution (or growth) in a ternary system of finite length has been modeled numerically using an implicit finite-difference method. The analysis has been applied to study the ferrite to austenite transformation in austenit...
J. M. Vitek, S. A. Vitek
Studies in neutron phase space cooling for cold and ultra-cold neutron sources
This thesis addresses problems in the phase space compression of neutrons in two different energy regimes. The first part applies to the cold neutron regime. We constructed a microscopic model for the neutron dynamic structure factor S(Q, o) of solid methane in phase II. The model treats the effects of molecular translations, intra-molecular vibrations and intra-molecular rotations as uncoupled. Total
Yunchang Shin
Gas-phase saturation and evaporative cooling effects during wet compression of a fuel aerosol under RCM conditions
Wet compression of a fuel aerosol has been proposed as a means of creating gas-phase mixtures of involatile diesel-representative fuels and oxidizer + diluent gases for rapid compression machine (RCM) experiments. The use of high concentration aerosols (e.g., {proportional_to}0.1 mL{sub fuel}/L{sub gas}, {proportional_to}1 x 10{sup 9} droplets/L{sub gas} for stoichiometric fuel loading at ambient conditions) can result in droplet-droplet interactions which lead to significant gas-phase fuel saturation and evaporative cooling during the volumetric compression process. In addition, localized stratification (i.e., on the droplet scale) of the fuel vapor and of temperature can lead to non-homogeneous reaction and heat release processes - features which could prevent adequate segregation of the underlying chemical kinetic rates from rates of physical transport. These characteristics are dependent on many factors including physical parameters such as overall fuel loading and initial droplet size relative to the compression rate, as well as fuel and diluent properties such as the boiling curve, vaporization enthalpy, heat capacity, and mass and thermal diffusivities. This study investigates the physical issues, especially fuel saturation and evaporative cooling effects, using a spherically-symmetric, single-droplet wet compression model. n-Dodecane is used as the fuel with the gas containing 21% O{sub 2} and 79% N{sub 2}. An overall compression time and compression ratio of 15.3 ms and 13.4 are used, respectively. It is found that smaller droplets (d{sub 0}{proportional_to} 2-3 {mu}m) are more affected by 'far-field' saturation and cooling effects, while larger droplets (d{sub 0}{proportional_to} 14 {mu}m) result in greater localized stratification of the gas-phase due to the larger diffusion distances for heat and mass transport. Vaporization of larger droplets is more affected by the volumetric compression process since evaporation requires more time to be completed even at the same overall fuel loading. All of the cases explored here yield greater compositional stratification than thermal stratification due to the high Lewis numbers of the fuel-air mixtures (Le{sub g} {proportional_to} 3.8). (author)
Goldsborough, S.S. [Department of Mechanical Engineering, Marquette University, Milwaukee, WI (United States); Johnson, M.V. [Energy Systems Division, Argonne National Laboratory, IL (United States); Zhu, G.S. [HDEP Performance and Emissions, DTNA - Detroit Diesel Corporation, Detroit, MI (United States); Aggarwal, S.K. [Department of Mechanical and Industrial Engineering, University of Illinois at Chicago, 1030 Engineering Research Facility, Chicago, IL (United States)
Phase II Testing of Liquid Cooling Garments Using a Sweating Manikin, Controlled by a Human Physiological Model
An Advanced Automotive Manikin (ADAM) developed at the National Renewable Energy Laboratory (NREL) is used to evaluate NASA's liquid cooling garments (LCGs) used in advanced space suits for extravehicular applications. The manikin has 120 separate heated/sweating zones and is controlled by a finite element physiological model of the human thermoregulatory system. Previous testing showed the thermal sensation and comfort followed the expected trends as the LCG inlet fluid temperature was changed. The Phase II test data demonstrates the repeatability of ADAM by retesting the baseline LCG. Skin and core temperature predictions using ADAM in an LCG/Arctic suit combination are compared to NASA physiological data to validate the manikin/model. Additional LCG configurations are assessed using the manikin and compared to the baseline LCG. Results can extend to other personal protective clothing, including HAZMAT suits, nuclear/biological/chemical protective suits, and fire protection suits.
Paul, Heather; Trevino, Luis; Bue,Grant; Rugh, John
On the use of a small-scale two-phase thermosiphon to cool high-power electronics
An experimental and analytical investigation of the steady-state thermal-hydraulic operating characteristics of a small-scale two-phase thermosiphon cooling actual power electronics are presented. Boiling heat transfer coefficients and circulation mass velocities were measured while varying heat load and pressure. Both a plain and augmented riser structure, utilizing micro-fins and reentrant cavities, were simultaneously tested. The boiling heat transfer coefficients increased with both increasing heat load and pressure. The mass velocity increased with increasing pressure while both increasing and then decreasing with increasing heat load. The reentrant cavity enhancement factor, a ratio of the augmented-to-plain riser nucleate boiling heat transfer coefficients, ranged from 1 to 1.4. High-speed photography revealed bubbly, slug, churn, wispy-annular and annular flow patterns. The experimental mass velocity and heat transfer coefficient data were compared to an analytical model with average absolute deviations of 16.3 and 26.3 percent, respectively.
Schrage, D. S.
Effects of Microstructures, Porosity and External Pressure on the Phase Transition of Ferroelectric Ceramics Upon Cooling
A micromechanics-based thermodynamics model is developed to predict the effects of internal stress, microstructures, porosity, and external hydrostatic pressure, on the phase transition of ferroelectric ceramics, with a special reference to the cubic?tetragonal transformation. The development makes use of the 3-D randomly oriented ellipsoidal inclusions containing an eigenstrain and eigen-polarization to represent the morphology of the transformed domains in the
Wenfang Li; George J. Weng
Phase 1 archaeological investigation, cultural resources survey, Hawaii Geothermal Project, Makawao and Hana districts, south shore of Maui, Hawaii
This report details the archaeological investigation of a 200 foot wide sample corridor extending approximately 9 miles along the southern portion of Maui within the present districts of Hana and Makawao. The survey team documented a total of 51 archaeological sites encompassing 233 surface features. Archaeological sites are abundant throughout the region and only become scarce where vegetation has been bulldozed for ranching activities. At the sea-land transition points for the underwater transmission cable, both Ahihi Bay and Huakini Bay are subjected to seasonal erosion and redeposition of their boulder shorelines. The corridor at the Ahihi Bay transition point runs through the Maonakala Village Complex which is an archaeological site on the State Register of Historic Places within a State Natural Area Reserve. Numerous other potentially significant archaeological sites lie within the project corridor. It is likely that rerouting of the corridor in an attempt to avoid known sites would result in other undocumented sites located outside the sample corridor being impacted. Given the distribution of archaeological sites, there is no alternative route that can be suggested that is likely to avoid encountering sites. Twelve charcoal samples were obtained for potential taxon identification and radiocarbon analysis. Four of these samples were subsequently submitted for dating and species identification. Bird bones from various locations within a lava tube were collected for identification. Sediment samples for subsequent pollen analysis were obtained from within two lava tubes. With these three sources of information it is hoped that paleoenvironmental data can be recovered that will enable a better understanding of the setting for Hawaiian habitation of the area.
Erkelens, C. [International Archaeological Research Inst., Inc., Honolulu, HI (United States)] [International Archaeological Research Inst., Inc., Honolulu, HI (United States)
Stability and Phase Noise Tests of Two Cryo-Cooled Sapphire Oscillators
A cryocooled Compensated Sapphire Oscillator (CSO), developed for the Cassini Ka-band Radio Science experiment, and operating in the 8K - 10K temperature range was previously demonstrated to show ultra-high stability of sigma(sub y) = 2.5 x 10 (exp -15) for measuring times 200 seconds less than or equal to tau less than or equal to 600 seconds using a hydrogen maser as reference. We present here test results for a second unit which allows CSO short-term stability and phase noise to be measured for the first time. Also included are design details of a new RF receiver and an intercomparison with the first CSO unit. Cryogenic oscillators operating below about 10K offer the highest possible short term stability of any frequency sources. However, their use has so far been restricted to research environments due to the limited operating periods associated with liquid helium consumption. The cryocooled CSO is being built in support of the Cassini Ka-band Radio Science experiment and is designed to operate continuously for periods of a year or more. Performance targets are a stability of 3-4 x 10 (exp -15) (1 second less than or equal to tau less than or equal to 100 seconds) and phase noise of -73dB/Hz @ 1Hz measured at 34 GHz. Installation in 5 stations of NASA's deep space network (DSN) is planned in the years 2000 - 2002. In the previous tests, actual stability of the CSO for measuring times tau less than or equal to 200 seconds could not be directly measured, being masked by short-term fluctuations of the H-maser reference. Excellent short-term performance, however, could be inferred by the success of an application of the CSO as local oscillator (L.O.) to the JPL LITS passive atomic standard, where medium-term stability showed no degradation due to L.O. instabilities at a level of (sigma)y = 3 x 10 (exp -14)/square root of tau. A second CSO has now been constructed, and all cryogenic aspects have been verified, including a resonator turn-over temperature of 7.907 K, and Q of 7.4 x 10 (exp 8). These values compare to a turn-over of 8.821 K and Q of 1.0 x 10 (exp 9) for the first resonator. Operation of this second unit provides a capability to directly verify for the first time the short-term (1 second less than or equal to tau less than or equal to 200 seconds) stability and the phase noise of the CSO units. The RF receiver used in earlier tests was sufficient to meet Cassini requirements for tau greater than or equal to 10 seconds but had short-term stability limited to 2-4 x 10 (exp -14) at tau = 1 second, a value 10 times too high to meet our requirements. A new low-noise receiver has been designed to provide approximately equal to 10-15 performance at 1 second, and one receiver is now operational, demonstrating again short-term CSO performance with H maser-limited stability. Short-term performance was degraded in the old receiver due to insufficient tuning bandwidth in a 100MHZ quartz VCO that was frequency-locked to the cryogenic sapphire resonator. The new receivers are designed for sufficient bandwidth, loop gain and low noise to achieve the required performance.
Dick, G. John; Wang, Rabi T.
Research on solar energy storage subsystems utilizing the latent heat of phase change of paraffin hydrocarbons for the heating and cooling of buildings
An analytical and experimental research program designed to assess the potential of a solar energy storage subsystem (thermal capacitor) using the latent heat of fusion of paraffin hydrocarbons for the heating and cooling of buildings, is described. An idealized model of a flat plate thermal capacitor based on uniaxial heat conduction with a change of phase and an absence of
J. A. Bailey; J. C. Mulligan; C. K. Liao; S. I. Guceri
Thermal analysis of n-alkane phase change material mixtures
Tests were performed to characterize the thermal behavior of it number of n-alkanes to be used as phase change materials (PCMs) in district cooling applications. Hexadecane and tetradecane were mixed in different fractions, and their thermal behavior was experimentally evaluated. Test results for melting temperature and fusion energy for laboratory grade hexadecane and tetradecane showed good agreement with datain the
Y. I. Chio; E. Choi; H. G. Lorsch
District heating strategy model: community manual
The US Department of Housing and Urban Development (HUD) and the US Department of Energy (DOE) cosponsor a program aimed at increasing the number of district heating and cooling systems. Twenty-eight communities have received HUD cooperative agreements to aid in a national feasibility assessment of district heating and cooling systems. The HUD/DOE program includes technical assistance provided by Argonne National Laboratory and Oak Ridge National Laboratory. Part of this assistance is a computer program, called the district heating strategy model, that performs preliminary calculations to analyze potential district heating and cooling systems. The model uses information about a community's physical characteristics, current electricity-supply systems, and local economic conditions to calculate heat demands, heat supplies from existing power plants and a new boiler, system construction costs, basic financial forecasts, and changes in air-pollutant emissions resulting from installation of a district heating and cooling system. This report explains the operation of the district heating strategy model, provides simplified forms for organizing the input data required, and describes and illustrates the model's output data. The report is written for three groups of people: (1) those in the HUD/DOE-sponsored communities who will be collecting input data, and studying output data, to assess the potential for district heating and cooling applications in their communiites; (2) those in any other communities who may wish to use the model for the same purpose; and (3) technical-support people assigned by the national laboratories to explain to community personnel how the model is used.
Hrabak, R. A.; Kron, Jr., N. F.; Pferdehirt, W. P.
Cooling Rates in Splat Cooling.
Calculations and experimental observations made on cooling rates during splat quenching are presented. Three possible types of cooling behavior are discussed: ideal cooling, intermediate cooling, and Newtonian cooling. The effects of splatting-process var...
R. C. Ruhl
Stochastic cooling
Stochastic cooling is the damping of betatron oscillations and momentum spread of a particle beam by a feedback system. In its simplest form, a pickup electrode detects the transverse positions or momenta of particles in a storage ring, and the signal produced is amplified and applied downstream to a kicker. The time delay of the cable and electronics is designed to match the transit time of particles along the arc of the storage ring between the pickup and kicker so that an individual particle receives the amplified version of the signal it produced at the pick-up. If there were only a single particle in the ring, it is obvious that betatron oscillations and momentum offset could be damped. However, in addition to its own signal, a particle receives signals from other beam particles. In the limit of an infinite number of particles, no damping could be achieved; we have Liouville's theorem with constant density of the phase space fluid. For a finite, albeit large number of particles, there remains a residue of the single particle damping which is of practical use in accumulating low phase space density beams of particles such as antiprotons. It was the realization of this fact that led to the invention of stochastic cooling by S. van der Meer in 1968. Since its conception, stochastic cooling has been the subject of much theoretical and experimental work. The earliest experiments were performed at the ISR in 1974, with the subsequent ICE studies firmly establishing the stochastic cooling technique. This work directly led to the design and construction of the Antiproton Accumulator at CERN and the beginnings of p anti p colliding beam physics at the SPS. Experiments in stochastic cooling have been performed at Fermilab in collaboration with LBL, and a design is currently under development for a anti p accumulator for the Tevatron.
Bisognano, J.; Leemann, C.
Microseismic monitoring for evidence of geothermal heat in the capital district of New York. Final report, Phases I-III
The seismic monitoring work of the geothermal project was initiated for the purpose of determining more exactly the relationship between seismicity and the postulated geothermal and related activity in the Albany-Saratoga Springs area in upstate New York. The seismic monitoring aspect of this work consisted of setting up and operating a network of seven seismograph stations within and around the study area capable of detecting and locating small earthquakes. To supplement the evidence from present day seismic activity, a list of all known historical and early instrumental earthquakes was compiled and improved from original sources for a larger region centered on the study area. Additional field work was done to determine seismic velocities of P and S phases by special recording of quarry blasts. The velocity results were used both as an aid to improve earthquake locations based on computer programs and to make inferences about the existence of temperature anomalies, and hence geothermal potential, at depths beneath the study area. Finally, the level in the continuous background earth vibration, microseisms, was measured throughout the study area to test a possibility that a relationship may exist at the surface between the level in microseisms and the geothermal or related activity. The observed seismic activity within the study area, although considerably higher (two to three times) than inferred from the historical and early instrumental data, is still not only low for a potential geothermal area but appears to be related to coherent regional tectonic stresses and not to the proposed more localized geothermal activity reflected in the mineralized, CO/sub 2/ rich spring discharge.
Thermal hydraulic analysis of two-phase closed thermosyphon cooling system for new cold neutron source moderator of Breazeale research reactor at Penn State
A cold neutron source cooling system is required for the Penn State's next generation cold neutron source facility that can accommodate a variable heat load up to about �10W with operating temperature of about 28K. An existing cold neutron source cooling system operating at the University of Texas Cold Neutron Source (TCNS) facility failed to accommodate heat loads upwards of 4W with the moderator temperature reaching a maximum of 44K, which is the critical temperature for the operating fluid neon. The cooling system that was used in the TCNS cooling system was a two-phase closed thermosyphon with a reservoir (TPCTR). The reservoir containing neon gas is kept at room temperature. In this study a detailed thermal analysis of the fundamental operating principles of a TPCTR were carried out. A detailed parametric study of the various geometric and thermo-physical factors that affect the limits of the operational capacity of the TPCTR investigated. A CFD analysis is carried out in order to further refine the heat transfer analysis and understand the flow structure inside the thermosyphon and the two-phase nucleate boiling in the evaporator section of the thermosyphon. In order to help the new design, a variety of ways of increasing the operating range and heat removal capacity of the TPCTR cooling system were analyzed so that it can accommodate the anticipated heat load of 10W or more. It is found, for example, that doubling the pressure of the system will increase the capacity index zeta by 50% for a system with an initial fill ratio FR of 1. A decrease in cryorefrigeration performance angle increases the capacity index. For example taking the current condition of the TCNS system and reducing the angle from the current value of �700 by half (�350) will increase the cooling power 300%. Finally based on detailed analytic and CFD analysis the best operating condition were proposed.
Habte, Melaku
High-resolution rovibrational spectroscopy of jet-cooled phenyl radical: the ?19 out-of-phase symmetric CH stretch.
Phenyl radical has been studied via sub-Doppler infrared spectroscopy in a slit supersonic discharge expansion source, with assignments for the highest frequency b2 out-of-phase C-H symmetric stretch vibration (?19) unambiguously confirmed by ?6 MHz (0.0002 cm(-1)) agreement with microwave ground state combination differences of McMahon et al. [Astrophys. J. 2003, 590, L61-64]. Least squares analysis of over 100 resolved rovibrational peaks in the sub-Doppler spectrum to a Watson Hamiltonian yields precision excited-state rotational constants and a vibrational band origin (?0 = 3071.8915(4) cm(-1)) consistent with a surprisingly small red-shift (0.9 cm(-1)) with respect to Ar matrix isolation studies of Ellison and co-workers [J. Am. Chem. Soc. 2001, 123, 1977]. Nuclear spin weights and inertial defects confirm the vibrationally averaged planarity and (2)A1 rovibronic symmetry of phenyl radical, with analysis of the rotational constants consistent with a modest C2v distortion of the carbon backbone frame due to partial sp rehybridization of the ? C radical-center. Most importantly, despite the number of atoms (N = 11) and vibrational modes (3N - 6 = 27), phenyl radical exhibits a remarkably clean jet cooled high-resolution IR spectrum that shows no evidence of intramolecular vibrational relaxation (IVR) phenomena such as local or nonlocal perturbations due to strongly coupled nearby dark states. This provides strong support for the feasibility of high-resolution infrared spectroscopy in other aromatic hydrocarbon radical systems. PMID:23537501
Buckingham, Grant T; Chang, Chih-Hsuan; Nesbitt, David J
High-Resolution Rovibrational Spectroscopy of Jet-Cooled Phenyl Radical: The ?19 Out-of-Phase Symmetric CH Stretch
Phenyl radical has been studied via sub-Doppler infrared spectroscopy in a slit supersonic discharge expansion source, with assignments for the highest frequency b2 out-of-phase C-H symmetric stretch vibration (-19) unambiguously confirmed by ?6 MHz (0.0002 cm-1) agreement with microwave ground state combination differences of McMahon et al. [Astrophys. J. 2003, 590, L61-64]. Least squares analysis of over 100 resolved rovibrational peaks in the sub-Doppler spectrum to a Watson Hamiltonian yields precision excited-state rotational constants and a vibrational band origin (-0 = 3071.8915(4) cm-1) consistent with a surprisingly small red-shift (0.9 cm-1) with respect to Ar matrix isolation studies of Ellison and co-workers [J. Am. Chem. Soc. 2001, 123, 1977]. Nuclear spin weights and inertial defects confirm the vibrationally averaged planarity and 2A1 rovibronic symmetry of phenyl radical, with analysis of the rotational constants consistent with a modest C2v distortion of the carbon backbone frame due to partial sp rehybridization of the ? C radical-center. Most importantly, despite the number of atoms (N = 11) and vibrational modes (3N - 6 = 27), phenyl radical exhibits a remarkably clean jet cooled high-resolution IR spectrum that shows no evidence of intramolecular vibrational relaxation (IVR) phenomena such as local or nonlocal perturbations due to strongly coupled nearby dark states. This provides strong support for the feasibility of high-resolution infrared spectroscopy in other aromatic hydrocarbon radical systems.
Buckingham, Grant T.; Chang, Chih-Hsuan; Nesbitt, David J.
Bellingham Phase 3, Engineering and technology development for a hot-water district-heating system employing thermal-energy storage
Thermal energy storage in a district heating system which requires the integration of customer consumption rates, weather and other system operating conditions, as well as economic payback is evaluated. Generic methods of approaching and evaluating these factors are essential to insure that the most economical district heating projects are selected for development and that those systems are designed and operated in the most cost effective manner. Also, governmental and legal guidelines for interfacing with users, financing, and municipal utility regulations are examined
Vanroyen, G. L.
Cooling of safety rods in the Savannah River K Reactor during the gamma heating phase of a postulated loss-of-coolant accident
This paper documents the heat-transfer analysis for the safety rod placed in a perforated guide tube during the gamma heating phase of a large-break loss of coolant accident in Savannah River K-reactor. The cooling mechanisms are natural convection to air and radiation to the surrounding structures. The limiting component is the guide tube. The guide tube is shown to remain
K. O. Pasamehmetoglu; C. Unal; F. E. Motley; S. B. Rodriguez
Hot-spot self-cooling effects on two-phase flow of R245fa in 85�m-wide multi-microchannels
Two-phase refrigerant flow boiling was shown to be effective in handling hot-spots. The footprint heat transfer coefficients followed the local heat flux and formed a self-compensating cooling mechanism by increasing the local heat transfer coefficient at the hot-spot. Data reduction using one-dimensional heat conduction overestimated the heat transfer coefficient at the hot-spots and underestimated it around its location. Heat spreading
E. Costa-Patry; J. Olivier; S. Paredes; J. R. Thome
Frictional cooling: Experimental results
The classical methods used in beam cooling are hard to be adapted for a beam of short-lived elementary particles. A novel method, the so-called frictional cooling - that is cooling a beam of low-energy charged particles by moderation in matter and acceleration in an electrostatic field - has been shown to be feasible. In our experiments performed in 1994/1995 a beam of short-lived particles was cooled for the first time ever. Utilizing frictional cooling on a beam of slow negative muons we observed increase in phase space density by about one order of magnitude.
M�hlbauer, M.; Daniel, H.; Hartmann, F. J.; Hauser, P.; Kottmann, F.; Petitjean, C.; Schott, W.; Taqqu, D.; Wojciechowski, P.
Proprties of the Carrol system and a machine design for solar-powered, air-cooled, absorption space cooling. Phase I and Phase II. Final report, September 1977March 1979
The name Carrol has been selected as a convenient short-hand designation for a prime candidate chemical system comprising ethylene glycol-lithium bromide as an absorbent mixture with water as a refrigerant. The instrumentation, methods of handling data and numerical results from a systematic determination of Carrol property data required to design an air cooled absorption machine based on this chemical system
Simulation Studies of Ionization Cooling
A {mu}{sup +}-{mu}{sup -} collider must compress the beam phase-space volume by a factor of {approximately}10{sup 6} to obtain high luminosity, and this beam cooling must occur before {mu}-decay. In this paper we present simulations of ionization cooling which explore the various conditions needed for cooling to collider conditions. Cooling by large factors is demonstrated and directions toward complete cooling scenarios are discussed.
Neuffer, D.; VanGinneken, A.
Exchange bias in phase-segregated Nd2/3Ca1/3MnO3 as a function of temperature and cooling magnetic fields
Exchange bias (EB) phenomena have been observed in Nd2/3Ca1/3MnO3 colossal magnetoresistance perovskite below the Curie temperature TC � 70 K and attributed to an antiferromagnetic-ferromagnetic (FM) spontaneous phase segregated state of this compound. Field cooled magnetic hysteresis loops exhibit shifts toward negative direction of the magnetic field axis. The values of exchange field HEB and coercivity HC are found to be strongly dependent of temperature and strength of the cooling magnetic field Hcool. These effects are attributed to evolution of the FM phase content and a size of FM clusters. A contribution to the total magnetization of the system due to the FM phase has been evaluated. The exchange bias effect decreases with increasing temperature up to TC and vanishes above this temperature with disappearance of FM phase. Relaxation of a non-equilibrium magnetic state of the compound manifests itself through a training effect also observed while studying EB in Nd2/3Ca1/3MnO3.
Fertman, Elena; Dolya, Sergiy; Desnenko, Vladimir; Pozhar, L. A.; Kaj�akov�, Marcela; Feher, Alexander
Restoration and repair of 30-year old cooling towers at the Paducah Gaseous Diffusion Plant, phase I
Early in 1980, a comprehensive reliability study was made to ascertain the ability of the present 30-year old recirculating water system to meet the anticipated load demand through the year 2000. The findings and recommendations of this study were used as a guide to schedule uprating and repairs. This paper deals with the underground distribution system and cooling tower repairs.
Restoration, testing and repair of 30-year old cooling towers at the Paducah Gaseous Diffusion Plant, Phase 2
Early in 1980, a comprehensive reliability study was made to ascertain the ability of the present 30 plus year old recirculating water system to meet the anticipated load demand through the year 2000. The anticipated load demand would require that 99% of the recirculating water equipment and cooling towers be in service at all times. This project was designed to
Restoration and repair of 30-year old cooling towers at the Paducah Gaseous Diffusion Plant, Phase I. Draft 1
Low-temperature two-phase micro-channel cooling for high-heat-flux thermal management of defense electronics
For a given heat sink thermal resistance and ambient temperature, the temperature of an electronic device rises fairly linearly with increasing device heat flux. This relationship is especially problematic for defense electronics, where heat dissipation is projected to exceed 1000 W\\/cm2 in the near future. Direct and indirect low temperature refrigeration cooling facilitate appreciable reduction in the temperature of both
Jaeseon Lee; Issam Mudawar
Copper content and cooling rate effects over second phase particles behavior in industrial aluminum�silicon alloy 319
This study was done choosing, the automotive aluminum alloy 319, to know how copper content act over Si, Cu and Fe particles versus applied different loads (stress) and cooling rate. This was done to know which particles fracture according to the morphology and size.This analysis was carried out has been using samples with different secondary dendrite arm spacing (SDAS) values
G. Garc�a-Garc�a; J. Espinoza-Cuadra; H. Mancha-Molinar
One-dimensional experiments of a natural circulation two-phase flow under an external reactor vessel cooling
During a severe accident in a nuclear power plant, a decay heat from a molten corium should be removed to maintain an integrity of the reactor vessel. This feasible strategy can be achieved by a External Reactor Vessel Cooling (ERVC) which requires a coolant to be circulated sufficiently between the reactor vessel and its insulation. For this reason, one-dimensional experiments
Jae Cheol Kim; Kwang Soon Ha; Rae Joon Park; Sang Baik Kim; Seong Wan Hong
Low-Temperature Two-Phase Microchannel Cooling for High-Heat-Flux Thermal Management of Defense Electronics
For a given heat sink thermal resistance and ambient temperature, the temperature of an electronic device rises fairly linearly with increasing device heat flux. This relationship is especially problematic for defense electronics, where heat dissipation is projected to exceed 1000 W\\/cm2 in the near future. Direct and indirect low-temperature refrigeration cooling facilitate appreciable reduction in the temperature of both coolant
Cooling concept integration. Phase I final technical report, October 1, 1979-July 31, 1981. [For pre-engineered metal buildings
Before specific test prototypes were developed, six potential evaporative roof cooling configurations with alternative storage and heat transfer mechanisms were examined, and preliminary cost estimates were made. Each system uses a wet roof system which sprays or floods the roof, allowing evaporative heat transfer to the environment. Finite difference thermal network methods were used for the evaluation of the systems. Detailed results including charts of the hourly heat flows during particular days are presented, and the performance is summarized for Las Vegas. (LEW)
Fraker, H.; Glennie, W.; Snyder, M.K.
Data-Driven Districts.
Describes the use of data-driven decision-making in four school districts: Plainfield Public Schools, Plainfield, New Jersey; Palo Alto Unified School District, Palo Alto, California; Francis Howell School District in eastern Missouri, northwest of St. Louis; and Rio Rancho Public Schools, near Albuquerque, New Mexico. Includes interviews with the�
LaFee, Scott
Thermal analysis of n-alkane phase change material mixtures. Progress report, January 1, 1991March 31, 1991
Electron cooling
The brief review of the most significant and interesting achievements in electron cooling method, which took place during last two years, is presented. The description of the electron cooling facilities�storage rings and traps being in operation or under development�is given. The applications of the electron cooling method are considered. The following modern fields of the method development are discussed: crystalline beam formation, expansion into middle and high energy electron cooling (the Fermilab Recycler Electron Cooler, the BNL cooler�recuperator, cooling with circulating electron beam, the GSI project), electron cooling in traps, antihydrogen generation, electron cooling of positrons (the LEPTA project).
Meshkov, I.; Sidorin, A.
Stochastic Cooling
Stochastic Cooling was invented by Simon van der Meer and was demonstrated at the CERN ISR and ICE (Initial Cooling Experiment). Operational systems were developed at Fermilab and CERN. A complete theory of cooling of unbunched beams was developed, and was applied at CERN and Fermilab. Several new and existing rings employ coasting beam cooling. Bunched beam cooling was demonstrated in ICE and has been observed in several rings designed for coasting beam cooling. High energy bunched beams have proven more difficult. Signal suppression was achieved in the Tevatron, though operational cooling was not pursued at Fermilab. Longitudinal cooling was achieved in the RHIC collider. More recently a vertical cooling system in RHIC cooled both transverse dimensions via betatron coupling.
Blaskiewicz, M.
The cryogenic characteristics in energy extraction of the four fifteen-meter-diameter superconducting solenoids of the g-2 magnet are reported in this paper. The energy extraction tests at full-current and half-current of its operating value were deliberately carried out for the quench analyses and evaluation of the cryogenic system. The temperature profiles of each coil mandrel and pressure profiles in its helium cooling tube during the energy extraction are discussed. The low peak temperature and pressure as well as the short recovery time indicated the desirable characteristics of the cryogenic system.
Cooling and alignment of ethylene molecules in supersonic seeded expansions: diagnostic and applicationto gas phase and surface scattering experiments
.��\\u000a Rotational cooling and collisional alignment \\u000a of ethylene molecules is induced by seeding effects in supersonic expansions\\u000a with lighter gas carriers such as He and Ne.\\u000a The dependencies of the degree of alignment on the rotational state,\\u000a on the final speed of the molecules and \\u000a on the diffusion angular cone have been characterized \\u000a by coupling two different\\u000a experimental methodologies. An
D. Cappelletti; F. Pirani; M. Scotoni; G. Demarchi; L. Vattuone; A. Gerbi; M. Rocca
Method and apparatus for maintaining multi-component sample gas constituents in vapor phase during sample extraction and cooling
An apparatus and method for diluting and cooling that is extracted from high temperature and/or high pressure industrial processes. Through a feedback process, a specialized, CFD-modeled dilution cooler is employed along with real-time estimations of the point at which condensation will occur within the dilution cooler to define a level of dilution and diluted gas temperature that results in a gas that can be conveyed to standard gas analyzers that contains no condensed hydrocarbon compounds or condensed moisture.
Farthing, William Earl (Pinson, AL) [Pinson, AL; Felix, Larry Gordon (Pelham, AL) [Pelham, AL; Snyder, Todd Robert (Birmingham, AL) [Birmingham, AL
Method and apparatus maintaining multi-component sample gas constituents in vapor phase during sample extraction and cooling
Farthing, William Earl (Pinson, AL); Felix, Larry Gordon (Pelham, AL); Snyder, Todd Robert (Birmingham, AL)
Liquid�solid phase equilibrium study of tetradecane and hexadecane binary mixtures as phase change materials (PCMs) for comfort cooling storage
Phase diagrams (equilibrium diagrams) are a convenient way of depicting the concentration�temperature�pressure relationships of a chemical system at equilibrium. They are invaluable to PCMs thermal storage researches and developers. In the present paper, the liquid�solid phase equilibrium of binary mixture system of tetradedcane and hexadecane has been studied. For theoretical evaluation of the thermodynamic equilibrium between the liquid phase and
Bo He; Viktoria Martin; Fredrik Setterwall
Proprties of the Carrol system and a machine design for solar-powered, air-cooled, absorption space cooling. Phase I and Phase II. Final report, September 1977-March 1979
The name Carrol has been selected as a convenient short-hand designation for a prime candidate chemical system comprising ethylene glycol-lithium bromide as an absorbent mixture with water as a refrigerant. The instrumentation, methods of handling data and numerical results from a systematic determination of Carrol property data required to design an air cooled absorption machine based on this chemical system are described. These data include saturation temperature, relative enthalpy, density, specific heat capacity, thermal conductivity, viscosity and absorber film heat transfer coefficient as functions of solution temperature and Carrol concentration over applicable ranges. For each of the major components of the absorption chiller, i.e., generator, chiller, absorber, condenser, heat exchanger, purge and controls, the report contains an assembly drawing and the principal operating characteristics of that component.
Biermann, W.J.
Pressure Drop, Heat Transfer, Critical Heat Flux, and Flow Stability of Two-Phase Flow Boiling Of Water and Ethylene Glycol/Water Mixtures - Final Report for Project 'Efficient Cooling In Engines with Nucleate Boiling.'
Because of its order-of-magnitude higher heat transfer rates, there is interest in using controllable two-phase nucleate boiling instead of conventional single-phase forced convection in vehicular cooling systems to remove ever increasing heat loads and t...
D. M. France J. L. Routbort W. Yu
A Neutron Star Stiff Equation of State Derived from Cooling Phases of the X-Ray Burster 4U 1724-307
Thermal emission during X-ray bursts is a powerful tool for determining neutron star (NS) masses and radii if the Eddington flux and the apparent radius in the cooling tail can be measured accurately and distances to the sources are known. We propose here an improved method of determining the basic stellar parameters using the data from the cooling phase of photospheric radius expansion (PRE) bursts covering a large range of luminosities. Because at that phase the blackbody apparent radius depends only on the spectral hardening factor (color correction), we suggest fitting the theoretical dependences of the color correction versus flux in Eddington units to the observed variations of the inverse square root of the apparent blackbody radius with the flux. For that we use a large set of atmosphere models for burst luminosities varying by three orders of magnitude and for various chemical compositions and surface gravities. We show that spectral variations observed during a long PRE burst from 4U 1724-307 are entirely consistent with the theoretical expectations for the passively cooling NS atmospheres. Our method allows us to more reliably determine both the Eddington flux (which is found to be smaller than the touchdown flux by 15%) and the ratio of the stellar apparent radius to the distance. We then find a lower limit on the NS radius of 14 km for masses below 2.3 M ?, independently of the chemical composition. These results suggest that the matter inside NSs is characterized by a stiff equation of state. We also find evidence in favor of hydrogen-rich accreting matter and obtain an upper limit to the distance of 7 kpc. We finally show that the apparent blackbody emitting area in the cooling tails of the short bursts from 4U 1724-307 is two times smaller than that for the long burst and their evolution does not follow the theory. This makes their usage for determining the NS parameters questionable and casts serious doubt on the results of previous works that used similar bursts from other sources for analysis.
Suleimanov, Valery; Poutanen, Juri; Revnivtsev, Mikhail; Werner, Klaus
Large signal modelling of cryogenically cooled GaAs field effect transistors for low phase noise oscillator design
We present an extensive study of microwave FET nonlinear electrical properties at liquid nitrogen temperature. Pulsed measurement, together with low frequency noise measurements and S-parameters measurements, have been used to extract a large signal model of a previously selected HEMT device. This model is particularly dedicated to microwave low phase noise cryogenic oscillators design
O. Llopis; J. Verdier; J. M. Dienot; P. Andre; R. Plana; J. Graffeuil
Benchmarking of thermal hydraulic loop models for Lead-Alloy Cooled Advanced Nuclear Energy System (LACANES), phase-I: Isothermal steady state forced convection
As highly promising coolant for new generation nuclear reactors, liquid Lead-Bismuth Eutectic has been extensively worldwide investigated. With high expectation about this advanced coolant, a multi-national systematic study on LBE was proposed in 2007, which covers benchmarking of thermal hydraulic prediction models for Lead-Alloy Cooled Advanced Nuclear Energy System (LACANES). This international collaboration has been organized by OECD/NEA, and nine organizations - ENEA, ERSE, GIDROPRESS, IAEA, IPPE, KIT/IKET, KIT/INR, NUTRECK, and RRC KI - contribute their efforts to LACANES benchmarking. To produce experimental data for LACANES benchmarking, thermal-hydraulic tests were conducted by using a 12-m tall LBE integral test facility, named as Heavy Eutectic liquid metal loop for integral test of Operability and Safety of PEACER (HELIOS) which has been constructed in 2005 at the Seoul National University in the Republic of Korea. LACANES benchmark campaigns consist of a forced convection (phase-I) and a natural circulation (phase-II). In the forced convection case, the predictions of pressure losses based on handbook correlations and that obtained by Computational Fluid Dynamics code simulation were compared with the measured data for various components of the HELIOS test facility. Based on comparative analyses of the predictions and the measured data, recommendations for the prediction methods of a pressure loss in LACANES were obtained. In this paper, results for the forced convection case (phase-I) of LACANES benchmarking are described.
Cho, Jae Hyun; Batta, A.; Casamassima, V.; Cheng, X.; Choi, Yong Joon; Hwang, Il Soon; Lim, Jun; Meloni, P.; Nitti, F. S.; Dedul, V.; Kuznetsov, V.; Komlev, O.; Jaeger, W.; Sedov, A.; Kim, Ji Hak; Puspitarini, D.
Muon cooling channels
A procedure uses the equations that govern ionization cooling, and leads to the most important parameters of a muon cooling channel that achieves assumed performance parameters. First, purely transverse cooling is considered, followed by both transverse and longitudinal cooling in quadrupole and solenoid channels. Similarities and differences in the results are discussed in detail, and a common notation is developed. Procedure and notation are applied to a few published cooling channels. The parameters of the cooling channels are derived step by step, starting from assumed values of the initial, final and equilibrium emittances, both transverse and longitudinal, the length of the cooling channel, and the material properties of the absorber. The results obtained include cooling lengths and partition numbers, amplitude functions and limits on the dispersion at the absorber, length, aperture and spacing of the absorber, parameters of the RF system that achieve the longitudinal amplitude function and bucket area needed. Finally, I compute the merit factor that describes the enhancement of the density in 6D phase space. The consequences of changes in the input parameters are discussed. The lattice parameters needed to achieve the assumed performance are summarized. The design proper of such a lattice, i.e. finding the precise arrangement of magnets, RF cavities, absorbers, etc., which has these properties is well beyond the scope of this document.
Eberhard K Keil
Thermomechanical modelling of residual stresses induced by martensitic phase transformation and cooling during quenching of railway wheels
A finite element (FE) method was used to study the formation of residual stresses in low carbon bainitic�martensitic rail wheels. The FE model combines a commercially available heat treatment software DANTE to the finite element analysis software ABAQUS. Material data which include thermo-mechanical properties and kinetics of phase transformations for low carbon bainitic�martensitic (LCBM) steels were obtained from dilatometry experiments
Siva N. Lingamanaik; Bernard K. Chen
Postexercise Cooling Rates in 2 Cooling Jackets
Abstract Context: Cooling jackets are a common method for removing stored heat accumulated during exercise. To date, the efficiency and practicality of different types of cooling jackets have received minimal investigation. Objective: To examine whether a cooling jacket containing a phase-change material (PC17) results in more rapid postexercise cooling than a gel cooling jacket and a no-jacket (control) condition. Design: Randomized, counterbalanced design with 3 experimental conditions. Setting: Participants exercised at 75% V?o2max workload in a hot climate chamber (temperature ?=? 35.0 � 1.4�C, relative humidity ?=? 52 � 4%) for 30�minutes, followed by postexercise cooling for 30�minutes in cool laboratory conditions (ambient temperature ?=? 24.9 � 1.8�C, relative humidity ?=? 39% � 10%). Patients or Other Participants: Twelve physically active men (age ?=? 21.3 � 1.1�years, height ?=? 182.7 � 7.1�cm, body mass ?=? 76.2 � 9.5�kg, sum of 6 skinfolds ?=? 50.5 � 6.9�mm, body surface area ?=? 1.98 � 0.14�m2, V?o2max ?=? 49.0 � 7.0�mL�kg?1�min?1) participated. Intervention(s): Three experimental conditions, consisting of a PC17 jacket, a gel jacket, and no jacket. Main Outcome Measure(s): Core temperature (TC), mean skin temperature (TSk), and TC cooling rate (�C/min). Results: Mean peak TC postexercise was 38.49 � 0.42�C, 38.57 � 0.41�C, and 38.55 � 0.40�C for the PC17 jacket, gel jacket, and control conditions, respectively. No differences were observed in peak TC cooling rates among the PC17 jacket (0.038 � 0.007�C/min), gel jacket (0.040 � 0.009�C/min), and control (0.034 � 0.010�C/min, P > .05) conditions. Between trials, no differences were calculated for mean TSk cooling. Conclusions: Similar cooling rates for all 3 conditions indicate that there is no benefit associated with wearing the PC17 or gel jacket.
Brade, Carly; Dawson, Brian; Wallman, Karen; Polglaze, Ted
District, Know Thyself
Finalists for the Broad Prize for Urban Education demonstrate that identifying strategies that fit the local context is essential in creating success for students. Long Beach Unified School District in California and Broward County Public Schools in Florida demonstrate how districts can use different strategies to achieve the same goals.
Tupa, Megan; McFadden, Ledyard
Chicago Park District
The Chicago Park District is one of the largest municipal park systems in the United States, containing over 8,100 acres of green space. All told, the District has 580 parks, including two city conservatories, a number of historic lagoons, and the iconic Clarence Buckingham Memorial Fountain. This website allows visitors the opportunity to learn about the District's mission, history, and long-range planning for existing parks and potential new sites. On the homepage, visitors can use the Find a Park feature to learn about these diverse spaces. Additionally, they can use the I Want To area to learn about park permits, volunteering, and reporting problems within the park system. The Events area is quite a find, as visitors can learn about some of the hundreds of events sponsored each year by the District. Finally, visitors can also use the Doing Business area to learn about the various entrepreneurial activities which are possible via the District.
How do Italian footwear industrial districts face globalization?
This paper examines the impact of globalization of production on the Italian footwear sector and investigates the structural changes taking place in some shoe districts as they join international production networks. The following questions are discussed: Are Italian footwear districts specializing in particular phases of the production cycle? Is there a trend towards the reduction of activities carried out within
Alessia Amighini; Roberta Rabellotti
Experimental study of an air-source heat pump for simultaneous heating and cooling � Part 2: Dynamic behaviour and two-phase thermosiphon defrosting technique
This article presents the concepts of an air-source heat pump for simultaneous heating and cooling (HPS) designed for hotels and smaller residential, commercial and office buildings in which simultaneous needs in heating and cooling are frequent. The main advantage of the HPS is to carry out simultaneously space heating and space cooling with the same energy input. Ambient air is
Paul Byrne; Jacques Miriel; Yves Lenat
Search for cool giant exoplanets around young and nearby stars. VLT/NaCo near-infrared phase-coronagraphic and differential imaging
Context. Spectral differential imaging (SDI) is part of the observing strategy of current and future high-contrast imaging instruments. It aims to reduce the stellar speckles that prevent the detection of cool planets by using in/out methane-band images. It attenuates the signature of off-axis companions to the star, such as angular differential imaging (ADI). However, this attenuation depends on the spectral properties of the low-mass companions we are searching for. The implications of this particularity on estimating the detection limits have been poorly explored so far. Aims: We perform an imaging survey to search for cool (Teff< 1000-1300 K) giant planets at separations as close as 5-10 AU. We also aim to assess the sensitivity limits in SDI data taking the photometric bias into account. This will lead to a better view of the SDI performance. Methods: We observed a selected sample of 16 stars (age <200 Myr, distance <25 pc) with the phase-mask coronagraph, SDI, and ADI modes of VLT/NaCo. Results: We do not detect any companions. As for the estimation of the sensitivity limits, we argue that the SDI residual noise cannot be converted into mass limits because it represents a differential flux, unlike what is done for single-band images, in which fluxes are measured. This results in degeneracies for the mass limits, which may be removed with the use of single-band constraints. We instead employ a method of directly determining the mass limits and compare the results from a combined processing SDI-ADI (ASDI) and ADI. The SDI flux ratio of a planet is the critical parameter for the ASDI performance at close-in separations (?1''). The survey is sensitive to cool giant planets beyond 10 AU for 65% and 30 AU for 100% of the sample. Conclusions: For close-in separations, the optimal regime for SDI corresponds to SDI flux ratios higher than ~2. According to the BT-Settl model, this translates into Teff ? 800 K, which is significantly lower than the methane condensation temperature (~1300 K). The methods described here can be applied to the data interpretation of SPHERE. In particular, we expect better performance with the dual-band imager IRDIS, thanks to more suitable filter characteristics and better image quality. Based on observations collected at the European Southern Observatory, Chile, ESO programs 085.C-0257A, 086.C-0164A, and 088.C-0893A.
Maire, A.-L.; Boccaletti, A.; Rameau, J.; Chauvin, G.; Lagrange, A.-M.; Bonnefoy, M.; Desidera, S.; Sylvestre, M.; Baudoz, P.; Galicher, R.; Mouillet, D.
Cool Suit
Acurex developed a heat stress alleviating, liquid cooled helmet liner for military pilots after a series of accidents in Vietnam suggested heat exhaustion as the cause. System pumped a cooled liquid through channels in the helmet liner proved effective in eliminating 40-60% of stored body heat.
A Non-Heating Experimental Study on the Two-Phase Natural Circulation through the Annular Gap between Reactor Vessel and Insulation under External Vessel Cooling
To improve the margin for IVR in high-power reactors, some design improvements of the vessel/insulation configuration to increase the heat removal rate by two-phase natural circulation have been proposed. To observe and evaluate the two-phase natural circulation phenomena through the gap between the reactor vessel and the insulation in the APR1400 under external reactor vessel cooling, the T-HERMES program has been performed, that is, the THERMES- SCALE, T-HERMES-SMALL, HERMES-HALF, and T-HERMES-CFD studies. In this paper, the HERMES-HALF study, which is one of the T-HERMES programs, is introduced. The HERMES-HALF is a non-heating experimental study on the two-phase natural circulation through the annular gap between the reactor vessel and the insulation. The objectives of this HERMES-HALF study are to observe and evaluate the two-phase natural circulation phenomena through the gap between the reactor vessel and the insulation in the APR1400. For these purposes, a half-scaled experimental facility is prepared utilizing the results of a scaling analysis to simulate the APR1400 reactor and insulation system. The behaviors of the boiling-induced two-phase natural circulation flow in the insulation gap are observed, and the liquid mass flow rates driven by the natural circulation loop and void fraction distribution are measured. And numerical analyses of the HERMES-HALF experiments using CFX-5.6 code have also been performed by solving unsteady, three-dimensional Reynolds-averaged Navier-Stokes equations for multiphase flows with the zero equation turbulence model. By the experimental flow observation and numerical predictions, weak recirculation flows in the near region of the shear key are observed. The void fraction monotonically increases from the water inlet to the shear key region. There exists a short decrease of the void fraction after passing through the shear key due to geometrical expansion and the recirculation flow caused by the shear key. The variation of the void fraction is small in the annular section. (authors)
Ha, K.S.; Park, R.J.; Cho, Y.R.; Kim, S.B.; Kim, H.D. [Thermal-Hydraulic Safety Research Division, Korea Atomic Energy Research Institute, 150 Deokjin-dong, Yuseong-gu, Daejeon, 305-353 (Korea, Republic of); Kim, H.M.; Kim, K.Y. [Dept. of Mechanical Engineering, Inha University, 253, Yonghyun-Dong, Namgu, Incheon, 402-751 (Korea, Republic of)
Tests were performed to characterize the thermal behavior of it number of n-alkanes to be used as phase change materials (PCMs) in district cooling applications. Hexadecane and tetradecane were mixed in different fractions, and their thermal behavior was experimentally evaluated. Test results for melting temperature and fusion energy for laboratory grade hexadecane and tetradecane showed good agreement with datain the literature. However, values for commercial grade hexadecane were found to be considerably lower. In the range of temperatures of interest for district cooling, mixtures of tetradecane and hexadecane can be treated as homogeneous substances. However, their heats of fusion are slightly lower than those of the pure substances. Their melting temperatures are also lower by an amount that can be predicted.
Chio, Y.I.; Choi, E.; Lorsch, H.G.
Phase coexistence in [111] electric-field-cooled 0.7Pb (Mg(1/3)Nb(2/3))O(3)-0.3PbTiO(3) crystals.
Features of phase coexistence in polydomain 0.7Pb(Mg(1/3)Nb(2/3))O(3)-0.3PbTiO(3) crystals cooled under an applied [111] electric field E have been investigated. A sequence of ferroelectric phases as well as the elastic matching between coexisting phases in heterophase states has been analysed for cases where the angle between the spontaneous polarization vector of each domain type and the applied E vector remains equal in each ferroelectric phase. This analysis is based on a method that involves distortion matrices of the polydomain phases and invariants of interfaces regarded as quadric surfaces separating the phases. Results are represented in a system of diagrams linking domain states and interfaces at first-order phase transitions observed in [111] field-cooled 0.7Pb(Mg(1/3)Nb(2/3))O(3)-0.3PbTiO(3) crystals. A 'fine' structure of the domain state-interface diagrams related to tetragonal-orthorhombic phase coexistence has been revealed. It has been shown that conditions for complete stress relaxation in different heterophase states are achieved for a phase sequence of [Formula: see text] tetragonal [Formula: see text] near single-domain orthorhombic [Formula: see text] single-domain monoclinic of the B type. PMID:21694067
Topolov, V Yu; Cao, Hu; Viehland, D
It Takes a District.
Describes Fontana (California) Unified School District's No Child Left Behind Act implementation plan, focusing on the use of project charts. Illustrates the project chart function with examples from Title I and Title X. (PKP)
Rosen, Karolee
Interconnecting District Heating Networks.
The National Energy Administration has, on behalf of the Swedish Government, investigated the potential for interconnecting district heating networks in Sweden. The purpose is twofold: by creating a large heat load, cheap energy sources like waste heat ca...
Geothermal district G1
Geothermal District G1 includes 37 northeastern California counties and six geothermal fields: Lake City, Susanville, Litchfield, Wendel, Amedee, and Casa Diablo. Electrical generation from geothermal resources occurs in three of the fields: Wendel, Amedee, and Casa Diablo. Low-temperature geothermal projects are underway throughout the district and are described in a road log format. The ten projects described are located at Big Bend, Glass Mountain, Bieber, Alturas, Cedarville, Lake City, Honey Lake Valley, Greenville, and in Sierra and Mono Counties.
Is a Monolithic Dome in Your District's Future?
Monolithic domes are less costly to build than traditional structures and can cost as much as 50 percent less to heat and cool. Districts across the country that have opted for monolithic-dome school facilities say their decision was a cost-effective alternative to conventional construction. (MLH)
Lanham, Carol
Evaporative Cooling of Sodium Atoms
Results of experiments on evaporative cooling of sodium atoms are presented. Atoms are loaded into a spherical quadrupole magnetic trap and are cooled by a novel technique, rf induced evaporation. The elastic collision cross section for cold sodium atoms is measured to be 6 10^{-12} cm^2 . These initial experiments result in an increase of phase space density of 190.
Kendall Bruce Davis
Simulation Studies of Ionization Cooling.
A (mu)(sup +)-(mu)(sup -) collider must compress the beam phase-space volume by a factor of (approximately)10(sup 6) to obtain high luminosity, and this beam cooling must occur before (mu)-decay. In this paper we present simulations of ionization cooling ...
D. Neuffer A. VanGinneken
Cooled railplug
The railplug is a plasma ignitor capable of injecting a high energy plasma jet into a combustion chamber of an internal combustion engine or continuous combustion system. An improved railplug is provided which has dual coaxial chambers (either internal or external to the center electrode) that provide for forced convective cooling of the electrodes using the normal pressure changes occurring in an internal combustion engine. This convective cooling reduces the temperature of the hot spot associated with the plasma initiation point, particularly in coaxial railplug configurations, and extends the useful life of the railplug. The convective cooling technique may also be employed in a railplug having parallel dual rails using dual, coaxial chambers.
Weldon, William F. (Austin, TX) [Austin, TX
Cool Vest
ILC, Dover Division's lightweight cooling garment, called Cool Vest was designed to eliminate the harmful effects of heat stress; increases tolerance time in hot environments by almost 300 percent. Made of urethane-coated nylon used in Apollo, it works to keep the body cool, circulating chilled water throughout the lining by means of a small battery-powered pump. A pocket houses the pump, battery and the coolant which can be ice or a frozen gel, a valve control allows temperature regulation. One version is self-contained and portable for unrestrained movement, another has an umbilical line attached to an external source of coolant, such as standard tap water, when extended mobility is not required. It is reported from customers that the Cool Vest pays for itself in increased productivity in very high temperatures.
A cold neutron source cooling system is required for the Penn State's next generation cold neutron source facility that can accommodate a variable heat load up to about �10W with operating temperature of about 28K. An existing cold neutron source cooling system operating at the University of Texas Cold Neutron Source (TCNS) facility failed to accommodate heat loads upwards of
Melaku Habte
Development of a single-family absorption chiller for use in a solar heating and cooling system. Phase III, final report. Volume II
The appendices provide supporting information on: properties of a chemical system for solar fired, air-cooled absorption equipment, air-side performance of a one-inch tube, absorber plate-fin coil, listings of the programs used for simulation and data reduction, and evaluation of the Carrier 3-ton chiller in an integrated heating and cooling system. (LEW)
Reimann, R.C.; Biermann, W.J.
The railplug is a plasma ignitor capable of injecting a high energy plasma jet into a combustion chamber of an internal combustion engine or continuous combustion system. An improved railplug is provided which has dual coaxial chambers (either internal or external to the center electrode) that provide for forced convective cooling of the electrodes using the normal pressure changes occurring in an internal combustion engine. This convective cooling reduces the temperature of the hot spot associated with the plasma initiation point, particularly in coaxial railplug configurations, and extends the useful life of the railplug. The convective cooling technique may also be employed in a railplug having parallel dual rails using dual, coaxial chambers. 10 figs.
Weldon, W.F.
Cooling Off
In this activity, learners are introduced to challenges of maintaining temperatures while living in space. Thinking and acting like scientists and engineers, learners experiment to learn how to measure the specific heat capacity (or simply, specific heat) of water and then design an improved cooling system like those used in spacesuits. This lesson is developed using a 5E model of learning. In the ENGAGE section of the lesson, learners look at NASA technology and its relationship to improvements in athletic clothing and equipment. They learn about technology in spacesuit design and the use of this technology in everyday life. Working in teams, students conduct experiments relating to specific heat capacity on a cooling system they design in the EXPLORE and EXPLAIN sections. They are challenged to improve the cooling system in the EXTEND section of this lesson. Learners assess their understanding and abilities throughout the lesson and revisit the Essential Questions during the EVALUATE section.
Microseismic monitoring for evidence of geothermal heat in the capital district of New York. Volume 5. Phases I-III. Final report
The seismic monitoring aspect of this work consisted of setting up and operating a network of seven seismograph stations within and around the study area capable of detecting and locating small earthquakes. To supplement the evidence from present day seismic activity, a list of all known historical and early instrumental earthquakes was compiled and improved from original sources for a larger region centered on the study area. Additional field work was done to determine seismic velocities of P and S phases by special recording of quarry blasts. The velocity results were used both as an aid to improve earthquake locations based on computer programs and to make inferences about the existence of temperature anomalies, and hence geothermal potential, at depths beneath the study area. Finally, the level in the continuous background earth vibration, microseisms, was measured throughout the study area to test a possibility that a relationship may exist at the surface between the level in microseisms and the geothermal or related activity. The observed seismic activity within the study area, although considerably higher (two to three times) than inferred from the historical and early instrumental data, is still not only low for a potential geothermal area but appears to be related to coherent regional tectonic stresses and not to the proposed more localized geothermal activity reflected in the mineralized, CO/sub 2/ rich spring discharge.
Competency: District Views from Southern California.
Educators from Fullerton Union High School District, Newport-Mesa Unified School District, Capistrano Unified School District, and Huntington Beach Union High School District describe their efforts toward developing competency-based curriculum to meet state mandates. (SJL)
Tyo, John
Advanced Phase Change Materials for Solar Passive Heating and Cooling of Residential Buildings: Annual Topical Report, May 29, 1986-May 29, 1987.
This report describes research conducted in testing hydrocarbons for use as heat storage compounds in solar heated and cooled buildings. Materials tested are crystalline alkyl hydrocarbons and butyl stearate/butyl palmitate. Experimental results are brief...
I. O. Salyer A. K. Sircar
Districts for 104th Congress
This is a polygon coverage of 104th Congressional District boundaries obtained from the U.S. Bureau of the Census. The 103rd Congress was the first Congress that reflected the reapportionment and delineation of congressional districts based on the 1990 census. The next (104th) Congress reflects redelineation of districts that occurred for six states: Georgia, Louisiana, Maine, Minnesota, South Carolina, and Virginia. Congressional Districts U.S. House of Representatives Census TIGER/Line Files
U.S. Bureau of the Census
School District Purchasing.
This chapter of "Principles of School Business Management" discusses the effective management of purchasing processes in a school district. These processes include obtaining materials, supplies, and equipment of maximum value for the least expense, and receiving, storing, and distributing the items obtained. The chapter opens with an overview of�
Natale, Joseph L.
Districts Weigh Obesity Screening
Parents of children in most elementary grades in Minnesota's Independent School District 191 receive an annual notice with potentially life-altering data for their children--and they are not state test scores, attendance rates, or grades. The notice contains the child's body mass index (BMI) score, which estimates whether the student has excess�
Butler, Kevin
Reykjavik District Heating System.
Reykjavik, Iceland, utilizes natural geothermal resources as the heat input for its district heating system. This system served about 8,700 of the 10,000 residences in 1970. The water used is non-corrosive, allowing the use of standard pipe and fittings. ...
J. Zoega G. Kristinsson
Districts Shun Stimulus Bids
In the final sprint to polish Race to the Top applications, hundreds of school districts shunned a shot at a share of $4 billion in grants by refusing to sign on to their states' plans for the federal competition. California officials had secured the signatures of 790 local education agencies (leas) late last week, including most of the state's�
Maxwell, Lesli A.
School District Budgeting.
This book is devoted exclusively to the budgeting process in school districts, unlike the more common generic budgeting texts. As such, it allows an in-depth treatment of both conceptual and practical aspects of budgeting in a single volume. By default, school business officials have had to rely on the state education accounting manual as their�
Hartman, William T.
Districts Tackling Meal Debt
School districts have resorted to hiring debt collectors, employing constables, and swapping out standard meals for scaled-back versions to try to coerce parents to pay off school lunch debt that, in recent years, appears to have surged as the result of a faltering economy and better record-keeping. While the average school lunch costs just about�
Shah, Nirvi
The Importance of Districts
Effectiveness studies have largely concentrated on the school as the unit of analysis, although an increasing number have directed their attention to the teacher as the main unit of interest. But policy is often directed through organisations at the district level or what is sometimes known as the Education Authority (EA). Few studies have�
Tymms, Peter; Merrell, Christine; Heron, Tara; Jones, Paul; Albone, Stephen; Henderson, Brian
District-Level Downsizing
Draconian cuts have become the order of business for many school districts since the economic recession hit in 2008. But for the coming school year, "draconian" has taken on an even harsher meaning, as states from California and Texas to Illinois and New York wrestle with deficits in the tens of billions of dollars and make multi-billion-dollar�
Schachter, Ron
Cooling vest
Inexpensive vest of heat-sealable urethane material, when strapped to person's body, presents significant uncomplicated cooling system for environments where heavy accumulation of metabolic heat exists. Garment is applicable to occupations where physical exertion is required under heavy protective clothing.
Kosmo, J.; Kane, J.; Coverdale, J.
A District Level Planning Model.
This report examines school district planning models in South Carolina. It focuses on three questions: (1) Of those school districts conducting some type of systematic planning, how many are producing strategic plans? Long-range plans? Accountability reports? (2) In those same districts, how many are preparing adequate program-management�
McHenry, W. E.; Achilles, C. M.
EPA Science Inventory
The USACE Division and District Boundary data contains the delination of Corps Division and District boundaries. District and Division Boundaries are based on the US political and watershed boundaries. In the mid 1990's, WES created the file by digitizing the 1984 Civil Wor...
Stochastic cooling of atoms using lasers
We propose a method to laser-cool atoms based on stochastic cooling, first developed at CERN to cool antiprotons. Fluctuations in the momentum distribution will be detected in a pump-probe configuration with far-detuned lasers, and the appropriate correction kick will be accomplished with optical dipole potentials. Each stage of an iterative cooling process will involve measurement and feedback, with phase space remixing in between. We discuss possible applications of this method to magnetically trapped atoms and molecules.
Raizen, M. G.; Koga, , J.; Sundaram, B.; Kishimoto, Y.; Takuma, H.; Tajima, T.
Cool Sportswear
New athletic wear design based on the circulating liquid cooling system used in the astronaut's space suits, allows athletes to perform more strenuous activity without becoming overheated. Techni-Clothes gear incorporates packets containing a heat-absorbing gel that slips into an insulated pocket of the athletic garment and is positioned near parts of the body where heat transfer is most efficient. A gel packet is good for about one hour. Easily replaced from a supply of spares in an insulated container worn on the belt. The products, targeted primarily for runners and joggers and any other athlete whose performance may be affected by hot weather, include cooling headbands, wrist bands and running shorts with gel-pack pockets.
Cool Science
Science is quite cool, but you don't need to tell this to the dedicated team at the Howard Hughes Medical Institute. Their website, Cool Science, entertains questions of all kinds, encourages young scientists to "get their hands dirty", and also provides educators with a range of resources, including interactive media features, lesson plans, and lab exercises. These materials are contained with six primary sections: "For Educators", "Biointeractive", "For Curious Kids", and "Ask A Scientist". Educators of all stripes can use the "For Educators" area to focus in on resources organized by type, topic, grade level, and also to sign up for the resources RSS feed. Moving on, the "Biointeractive" area features archived video lectures, virtual labs, and another series of animations on stem cells, cancer, and immunology. There's a great deal to explore here, and it's a site that anyone with an interest in science will want to share with others.
Cool It!
In this fun hands-on activity, learners use simple materials to investigate evaporation. How can the evaporation of water on a hot day be used to cool an object? Find out the experimental way! The activity is based on an episode of Cyberchase called "Digit's B-Day Surprise" and was developed to capture kids' interest in math using the appeal of the popular PBS series.
Wnet; Title Entertainment, Inc.
Effect of oxygen on phase formation and thermal stability of slowly cooled Zr{sub 65}Al{sub 7.5}Cu{sub 17.5}Ni{sub 10} metallic glass
The effect of small amounts of oxygen (0.28--0.6 at.%) on the phase formation and the thermal stability of bulk samples of the Zr{sub 65}Al{sub 7.5}Cu{sub 17.5}Ni{sub 10} alloy prepared by die casting into a copper mould has been studied by X-ray diffraction, microstructural characterization and differential scanning calorimetry. In contrast to rapidly quenched ribbons, the crystalline volume fraction in slowly cooled bulk samples increases with increasing oxygen content. Oxygen triggers the formation of a metastable f.c.c. NiZr{sub 2}-type crystalline phase which also depends on the local cooling conditions during casting. The processes o the oxygen-induced crystallization are discussed in detail considering initial nucleation of metastable f.c.c. crystalline phases. Furthermore, there is a strong influence of the oxygen content on the thermal stability during constant-rate heating to elevated temperatures. With increasing oxygen content a drastic reduction of the supercooled liquid region is observed, resulting mainly from a change of the crystallization sequence from a single- to a double-step process which is attributed to the oxygen-triggered formation and the subsequent transformation of the metastable f.c.c. phase.
Gebert, A.; Eckert, J.; Schultz, L. [IFW Dresden (Germany). Inst. fuer Metallische Werkstoffe] [IFW Dresden (Germany). Inst. fuer Metallische Werkstoffe
Santa Ana Pueblo Assessment of District Heating and Cooling.
The Santa Ana Pueblo American Indian Tribe, numbering approximately 600 persons occupies two sites, totalling about 60,000 acres, northwest of Albuquerque, New Mexico. With the aid of consultants it has investigated the community's use of energy and a num...
H. Jenkins M. Giddings
Alabama district flood plan
The purpose of this flood plan is to outline and record advance planning for flood emergencies, so that all personnel will know the general plan and have a ready-reference for necessary information. This will ensure that during any flood event, regardless of the extent or magnitude, the resources of the District can be mobilized into a maximum data collection operation with a mimimum of effort.
Hedgecock, T. Scott; Pearman, J. Leroy; Stricklin, Victor E.
Mergers, cooling flows, and evaporation
Mergers (the capture of cold gas, especially) can have a profound influence on the hot coronal gas of early-type galaxies and clusters, potentially inducing symptoms hitherto attributed to a cooling flow, if thermal conduction is operative in the coronal plasma. Heat can be conducted from the hot phase into the cold phase, simultaneously ionizing the cold gas to make optical filaments, while locally cooling the coronal gas to mimic a cooling-flow. If there is heat conduction, though, there is no standard cooling-flow since radiative losses are balanced by conduction and not mass deposition. Amongst the strongest observational support for the existence of cooling-flows is the presence of intermediate temperature gas with x-ray emission-line strengths in agreement with cooling-flow models. Here, x-ray line strengths are calculated for this alternative model, in which mergers are responsible for the observed optical and x-ray properties. Since gas around 10(exp 4) K is thermally stable, the cold cloud need not necessarily evaporate and hydrostatic solutions exist. Good agreement with the x-ray data is obtained. The relative strengths of intermediate temperature x-ray emission lines are in significantly better agreement with a simple conduction model than with published cooling-flow models. The good agreement of the conduction model with optical, infrared and x-ray data indicates that significantly more theoretical effort into this type of solution would be profitable.
Sparks, W. B.
Decentralization: The Administrator's Guidebook to School District Change.
The school district decentralization process is described in this guidebook, which focuses on the administrator's role in implementation. Three chapters are organized around the three phases of decentralization--exploration, trial, and commitment. Each phase is examined in terms of the real-life experiences of administrators and other�
Brown, Daniel J.
Sorption cooling: a valid extension to passive cooling
Passive cooling has shown to be a very dependable cryogenic cooling method for space missions. Several missions employ passive radiators to cool down their delicate sensor systems for many years, without consuming power, without exporting vibrations or producing electromagnetic interference. So for a number of applications, passive cooling is a good choice. At lower temperatures, the passive coolers run into limitations that prohibit accommodation on a spacecraft. The approach to this issue has been to find a technology able to supplement passive cooling for lower temperatures, which maintains as much as possible of the advantages of passive coolers. Sorption cooling employs a closed cycle Joule-Thomson expansion process to achieve the cooling effect. Sorption cells perform the compression phase in this cycle. At a low temperature and pressure, these cells adsorb the working fluid. At a higher temperature they desorb the fluid and thus produce a high-pressure flow to the restriction in the cold stage. The sorption process selected for this application is of the physical type, which is completely reversible. It does not suffer from degradation as is the case with chemical sorption of e.g. hydrogen in metal hydrides. Sorption coolers include no moving parts except for some check valves, they export neither mechanical vibrations nor electromagnetic interference, and are potentially very dependable due to their simplicity. The required cooling temperature determines the type of working fluid to be applied. Sorption coolers can be used in conjunction with passive cooling for heat rejection at different levels. This paper starts with a brief discussion on applications of passive coolers in different types of orbits and the limitations on passive cooling at low cooling temperatures. Next, the working principle of sorption cooling is summarized. The DARWIN mission is chosen as an example application of sorption and passive cooling and special attention is paid to the reduction of the radiator area needed by the sorption cooler. By examining the performance of alternative working fluids suitable for different cooling temperatures, the application field of this type of sorption cooling is currently expanded.
Doornink, Jan; Burger, Johannes; ter Brake, Marcel
Sorption cooling: A valid extension to passive cooling
Passive cooling has shown to be a very dependable cryogenic cooling method for space missions. Several missions employ passive radiators to cool down their delicate sensor systems for many years, without consuming power, without exporting vibrations or producing electromagnetic interference. So for a number of applications, passive cooling is a good choice. At lower temperatures, the passive coolers run into limitations that prohibit accommodation on a spacecraft. The approach to this issue has been to find a technology able to supplement passive cooling for lower temperatures, which maintains as much as possible of the advantages of passive coolers. Sorption cooling employs a closed cycle Joule-Thomson expansion process to achieve the cooling effect. Sorption cells perform the compression phase in this cycle. At a low temperature and pressure, these cells adsorb the working fluid. At a higher temperature they desorb the fluid and thus produce a high-pressure flow to the expander in the cold stage. The sorption process selected for this application is of the physical type, which is completely reversible. It does not suffer from degradation as is the case with chemical sorption of, e.g., hydrogen in metal hydrides. Sorption coolers include no moving parts except for some check valves, they export neither mechanical vibrations nor electromagnetic interference, and are potentially very dependable due to their simplicity. The required cooling temperature determines the type of working fluid to be applied. Sorption coolers can be used in conjunction with passive cooling for heat rejection at different levels. This paper starts with a brief discussion on applications of passive coolers in different types of orbits and on the limitations of passive cooling for lower cooling temperatures. Next, the working principle of sorption cooling is summarized. The DARWIN mission is chosen as an example application of sorption and passive cooling and special attention is paid to the reduction of the radiator area needed by the sorption cooler. The application field of this type of sorption cooling in space missions is currently being expanded by examining the performance of alternative working fluids, suitable for different cooling temperatures.
Doornink, D. J.; Burger, J. F.; ter Brake, H. J. M.
Metallographic cooling rates of group IIF iron meteorites
Metallographic cooling rates have been calculated for all five members of group IIF using two different techniques. We have determined cooling rates of ~5 deg C\\/Ma based on Ni profiles through the taenite rim enclosing kamacite spindles. Ni profiles through the kamacite phase are less precise cooling rate indicators, but suggest a cooling rate of ~1 deg C\\/Ma within an
Kaare L. Rasmussen; Henning Haack; Finn Ulff-M�ller
"Strategic Review of FY06 District & School-Level Resources". In Fulfillment of a Memorandum of Understanding between: The Los Angeles Unified School District (LAUSD) and The Unified Teachers of Los Angeles (UTLA). Phase II- Final ERS Report. An Executive Summary and Management Brief Series
In the fall of 2006, Los Angeles Unified School District (LAUSD) and the Unified Teachers of Los Angeles (UTLA) signed a memorandum of understanding (MOU) that called for a third-party research firm to analyze resource use across the Los Angeles school system. Education Resource Strategies (ERS) was chosen to conduct this analysis. The study was�
Frank, Stephen; Travers, Jonathan
Wet-dry cooling demonstration. Test results
A large-scale test of dry/wet cooling using the ammonia phase-change system, designated the Advanced Concepts Test (ACT), has been operated at Pacific Gas and Electric Company's Kern Station at Bakersfield, California. The facility is capable of condensing 60,000 lbs/h of steam from a small house turbine. Two different modes of combining dry and evaporative cooling have been tested. One uses deluge cooling in which water is allowed to flow over the fins of the dry (air-cooled) heat exchanger on hot days; the other uses a separate evaporative condenser in parallel to the dry heat exchanger. A third mode of enhancing the dry cooling system, termed capacitive cooling has been tested. In this system, the ammonia-cooled steam condenser is supplemented by a parallel conventional water-cooled condenser with water supplied from a closed system. This water is cooled during off-peak hours each night by an ammonia heat pump which rejects heat through the ACT Cooling Tower. If operated over the period of a year, each of the wet/dry systems would use only 25% of the water normally required to reject this heat load in an evaporative cooling tower. The third would consume no water, the evaporative cooling being replaced by the delayed cooling of the closed system water supply.
Allemann, R.T.; DeBellis, D.E.; Werry, E.V.; Johnson, B.M.
75 FR 35778 - Modesto Irrigation District and Turlock Irrigation District; Notice of Preliminary Permit...
Federal Register 2010, 2011, 2012, 2013
...Commission [Project No. 12745-002] Modesto Irrigation District and Turlock Irrigation District; Notice of Preliminary Permit Application...16, 2010. On February 1, 2010, Modesto Irrigation District and Turlock Irrigation District...
Thermobarometry for 4?-n-Octylbiphenyl-4-carbonitrile in Metal Tube Berthelot Method and Polymorphism in Crystalline Phase of 4?-n-Octylbiphenyl-4-carbonitrile Found through Cooling Paths in Negative-Pressure Range
The Berthelot method has been used for generating negative pressure in a liquid sealed in a container by a temperature cycle. We introduce its thermodynamic principles and experimental procedures for observing the first-order phase transitions between the condensed phases of a thermotropic liquid crystal. In order to check the methodology, we measure the pressure (P) versus temperature (T) relations of 4?-n-octylbiphenyl-4-carbonitrile (8CB) sealed in a metal tube at various densities using the Berthelot method. Two results are reported: (i) the P-T phase diagram of 8CB is drawn in a triangular region bounded by three points, namely, (0.5 �C, 0 bar), (55 �C, +730 bar), and (75 �C, 0 bar) and (ii) the polymorphism of 8CB�s crystalline phase is detected only by cooling paths in the negative-pressure range; two melting points immediately below 10.5 and 15.8 �C, are measured for crystals formed upon cavitation in �super-expanded� smectic phase between -50 and -110 bar, while the reported melting point, 21 �C, is measured for crystals formed in the supercooled smectic phase under positive pressures. The thermobarometry of thermotropic liquid crystals is feasible by the metal tube Berthelot method, and its extension in the negative-pressure range will be interesting for the study of organic compounds.
Ohde, Yoshihito; Tanzawa, Yasutoshi; Motoshita, Kaname; Hiro, Kazuki
Analysis of County School Districts in Arkansas.
The 1948, Arkansas School District Reorganization Act was passed in an effort to reduce the 1589 small school districts to a smaller number. Those districts not consolidated would form county districts. As of the 1967-68 school year, 26 of these county districts remained. The purpose of this study was to provide information drawing attention to�
Budd, Karol B.; Charlton, J.L.
Research District Seeing Growth
Monthly economic diversity column for the Tri-City Herald (May 2012) - excerpt follows: It�s been a while since I�ve updated you on the Tri-Cities Research District, most certainly not for lack of new activity over the past several months. In fact, much has happened, and there�s more to come. I think many of us see new land development and construction as indicative of current or impending economic growth. So those of you who have ventured into North Richland either via Stevens Drive or George Washington Way lately have probably begun sensing and anticipating that such growth is afoot.
Madison, Alison L.
Energy storage using phase-change materials for active solar heating and cooling: an evaluation of future research and development directions
The current state of the art and commercial potential of active solar heating and cooling systems for buildings, and, in particular, the use of thermal energy storage with these systems are assessed. This assessment is used to determine the need for advanced latent heat storage subsystems in these applications and priorities for their development. Latent storage subsystems are advantageous in applications where their compactness may be exploited. These subsystems could facilitate storage in retrofit applications in which storage would be physically impossible otherwise.
Borkowski, R.J.; Stovall, T.K.; Kedl, R.J.; Tomlinson, J.J.
Calculation and visual displaying of the water chemistry conditions in return cooling systems at thermal power stations
Matters concerned with treatment of cooling water at thermal power stations are addressed. Problems arising during operation of return cooling systems equipped with cooling towers are analyzed. The software used for monitoring, control, and indication of the hydraulic and water chemistry operating conditions of the circulation system at the Yaivinsk district power station is considered.
Ochkov, V. F.; Orlov, K. A.; Ivanov, E. N.; Makushin, A. A.
District Support of School Improvement: Highlights from Three Districts. Newsletter
This newsletter addresses various supports that districts are utilizing to help keep students in school and on the path to graduation. Described herein are three districts that have been particularly successful in raising student achievement--even though they differ in their specific strategies, fund allocation, and demographic composition. A�
Center for Comprehensive School Reform and Improvement, 2009
Conceptual Design Study of Geothermal District Heating of a Thirty-House Subdivision in Elko, Nevada, Using Existing Water-Distribution Systems, Phase III. Final Technical Report, October 1, 1979-September 30, 1980.
A conceptual design study for district heating of a 30-home subdivision located near the southeast extremity of the city of Elko, Nevada is presented. While a specific residential community was used in the study, the overall approach and methodologies are...
D. R. Pitts
Thermal analysis of n-alkane phase change material mixtures. Progress report, January 1, 1991--March 31, 1991
Georgetown Historic District Survey: Georgetown, South Carolina.
The Georgetown Historic District Survey was conducted within the boundaries of the Georgetown National Register Historic District in the City of Georgetown, South Carolina. The 1971 National Register nomination form for the Georgetown Historic District es...
E. Jenkins G. Henry
A Tale of Two Districts
These days, everyone seems to be wringing their hands about how to construct new evaluation systems that will make teachers better. This unnecessary angst has led to crazy experiments in reform that have embraced churn for the sake of churn, put school districts at risk, and demoralized many of the most talented teachers. A few school districts,�
Simon, Mark
Internal Auditing for School Districts.
This book provides guidelines for conducting internal audits of school districts. The first five chapters provide an overview of internal auditing and describe techniques that can be used to improve or implement internal audits in school districts. They offer information on the definition and benefits of internal auditing, the role of internal�
Cuzzetto, Charles
Cab Heating and Cooling
Schneider National, Inc., SNI, has concluded the Cab Heating and Cooling evaluation of onboard, engine off idling solutions. During the evaluation period three technologies were tested, a Webasto Airtronic diesel fired heater for cold weather operation, and two different approaches to cab cooling in warm weather, a Webasto Parking Cooler, phase change storage system and a Bergstrom Nite System, a 12 volt electrical air conditioning approach to cooling. Diesel fired cab heaters were concluded to provide adequate heat in winter environments down to 10 F. With a targeted idle reduction of 17%, the payback period is under 2 years. The Webasto Parking Cooler demonstrated the viability of this type of technology, but required significant driver involvement to achieve maximum performance. Drivers rated the technology as ''acceptable'', however, in individual discussions it became apparent they were not satisfied with the system limitations in hot weather, (over 85 F). The Bergstrom Nite system was recognized as an improvement by drivers and required less direct driver input to operate. While slightly improved over the Parking Cooler, the hot temperature limitations were only slightly better. Neither the Parking Cooler or the Nite System showed any payback potential at the targeted 17% idle reduction. Fleets who are starting at a higher idle baseline may have a more favorable payback.
Damman, Dennis
Solar powered cooling device
The system contains an unique solar collector for transferring heat energy from the sun to a solution comprising a two-phase refrigerant and a fluid absorbent. Solar radiation causes a vaporization of the refrigerant which exits from the solar panel through a separate path from the remainder of the fluid. The vaporized refrigerant is returned to a liquid state and passed through an evaporator in a lower pressure environment for producing a cooling effect. The refrigerant is recombined with the absorbent and returned to the solar collector in a high pressure environment. Three modes of operation are included in the system. Continuous cooling is the first mode. The second mode consists of storing the liquid refrigerant after separation from the refrigerant absorbent fluid. The refrigerant and absorbent are stored for future use. The third mode of operation provides cooling in the absence of solar radiation by the use of the stored refrigerant and subsequent combination of the refrigerant with absorbent which fluid is then stored in a separate reservoir. The system also is provided with a solar tracking arrangement by which one or more solar collectors will be automatically oriented directly toward the sun for assuring maximum utilization of the sun's energy.
Ferriera, C.R.
Pressure drop, heat transfer, critical heat flux, and flow stability of two-phase flow boiling of water and ethylene glycol/water mixtures - final report for project "Efficent cooling in engines with nucleate boiling."
Because of its order-of-magnitude higher heat transfer rates, there is interest in using controllable two-phase nucleate boiling instead of conventional single-phase forced convection in vehicular cooling systems to remove ever increasing heat loads and to eliminate potential hot spots in engines. However, the fundamental understanding of flow boiling mechanisms of a 50/50 ethylene glycol/water mixture under engineering application conditions is still limited. In addition, it is impractical to precisely maintain the volume concentration ratio of the ethylene glycol/water mixture coolant at 50/50. Therefore, any investigation into engine coolant characteristics should include a range of volume concentration ratios around the nominal 50/50 mark. In this study, the forced convective boiling heat transfer of distilled water and ethylene glycol/water mixtures with volume concentration ratios of 40/60, 50/50, and 60/40 in a 2.98-mm-inner-diameter circular tube has been investigated in both the horizontal flow and the vertical flow. The two-phase pressure drop, the forced convective boiling heat transfer coefficient, and the critical heat flux of the test fluids were determined experimentally over a range of the mass flux, the vapor mass quality, and the inlet subcooling through a new boiling data reduction procedure that allowed the analytical calculation of the fluid boiling temperatures along the experimental test section by applying the ideal mixture assumption and the equilibrium assumption along with Raoult's law. Based on the experimental data, predictive methods for the two-phase pressure drop, the forced convective boiling heat transfer coefficient, and the critical heat flux under engine application conditions were developed. The results summarized in this final project report provide the necessary information for designing and implementing nucleate-boiling vehicular cooling systems.
Yu, W.; France, D. M.; Routbort, J. L. (Energy Systems)
Development of a single-family absorption chiller for use in a solar heating and cooling system. Phase III, final report. Volume I
This is a hardware oriented project to demonstrate the feasibility of the solar fired, air cooled, absorption cooling of residential and commercial buildings. Beginning with design accuracy property data on a new chemical system applicable to air cooled absorption equipment, a breadboard machine was constructed in order to gain experience with system dynamics, chemical stability and overall performance. Employing heat transfer data and operating characteristics obtained from the breadboard an attempt was made to design and build a first generation prototype. A problem with the first heat transfer additive used caused the absorber to operate unsatisfactorily. A second, more refined, prototype was designed, constructed and tested incorporating the previous experience and heat transfer data as well as a new heat transfer additive. Although this prototype did not quite meet design capacity (85%), it surpassed design COP (0.75 vs 0.72) and performed stably without the signs of chemical degradation present in the previous prototype. Two more identical machines are being operated during field test in actual solar systems. After the successful operation of the 10 kW machine, it was decided to design and construct a larger scaled-up prototype for use in commercial applications. An appropriate size seemed to be about 70 kW. After considerable design effort a satisfactory size and design was achieved and constructed. In general, the 70 kW machine behaved much like the 10 kW, again producing about 80% of capacity but with varying COP's (probably due to the transient nature of the testing).
Cooling tower
This patent describes a cooling tower comprising: an outer structure composed of a side wall and a top cover; the top cover having an opening on its center with a deflection device for reducing re-circulation of air within the housing; a motor which is fixed in a motor seat and whose shaft forms a spindle which rotates a rotatable cylinder; a rotatable cylinder having sides which have a plurality of small apertures, a centrifugal fan being an integral part of the rotating cylinder, the bottom portion of the cylinder engaging the shaft of the motor, the centrifugal fan comprising: a first flange on the top portion, a second flange on the portion with apertures, a plurality of blades which are equally spaced and fixed between the first and second flanges; a screen positioned concentrically around the rotatable cylinder and secured onto the inside of the top cover of the outer structure, the screen comprising a net and a frame, the frame further comprising a flange and skirt, the frame being secured onto the inside of the top cover of the outer structure with the flange, the skirt extending upwards and inwards through the bottom portion of the rotatable cylinder, the net adherent to the frame.
Liu, W.H.
Directions for the '80s: Educational Master Plan. San Francisco Community College District.
Designed to assist staff in the San Francisco Community College District (SFCCD) in synthesizing the trends, events and issues that are likely to influence educational programs and services, this master plan assesses the district's internal and external environments and describes the SFCCD's two-phase planning process. Chapter 1 discusses the�
Duncan-Hall, Tyra L., Ed.
Advanced energy transmission fluids for heating and cooling systems
The U.S. Department of Energy (DOE) is sponsoring a comprehensive program to develop high-performance energy transmission fluids for use in district heating and cooling (DHC) systems. These fluids would substantially reduce flow frictional losses and enhance heat transfer. In system enhancement scoping studies, the fluids have been shown to yield potentially significant upfront capital equipment cost reductions by allowing the
K. E. Kasza; S. U. Choi; J. Kaminsky
Mars Pathfinder mechanically pumped cooling loop
A mechanically pumped single-phase cooling loop was successfully flown on the Mars Pathfinder (MPF) Spacecraft which safely landed on the Martian surface on July 4, 1997. One of the key technologies that enabled the mission to succeed was an active heat rejection system (HRS) used to cool the electronics on the spacecraft during its seven-month cruise from Earth to Mars.
Birur, G. C.
Dilemmas Presented by State Agency Takeovers of Local School Districts.
During the 1988-89 school year, two local school districts were placed into "Phase III" of the Kentucky Educational Improvement Act (1978), a category of state receivership in which much local decision-making power was transferred to Kentucky Department of Education officials. When state education department intervention occurs, major issues arise�
Steffy, Betty E.
New Jersey's Plan to Intervene in Deficient School Districts.
Implemented in January 1984, the two-part New Jersey local assistance plan calls for state intervention and possible takeover in districts that are unable, after going through the Level I and Level II monitoring and correction processes, to meet state certification standards. The first phase of the intervention plan, a Level III monitoring�
New Jersey State Dept. of Education, Trenton. Div. of County and Regional Services.
Phase Change
In this activity, students explore phase change at a molecular level. They trace the path of an atom to view intermolecular interactions and investigate how temperature relates to phase change. Upon activity completion, students will be able to give examples of phase change, explain how the input of energy into a system affects the state of matter, and describe how both latent heat and evaporative cooling play a role in changes of phase.
Consortium, The C.
A positive model of special district formation
New special district governments account for most of the growth in the number of governments in the US over the past few decades. This paper presents a positive model of the formation of special districts that provide goods via an increasing-returns-to-scale technology, such as water or sewerage districts. The formation of a special district is modeled as a noncooperative game
D. Andrew Austin
Comments on optical stochastic cooling
An important necessary condition for transverse phase space damping in the optical stochastic cooling with transit-time method is derived. The longitudinal and transverse damping dynamics for the optical stochastic cooling is studied. The authors also obtain an optimal laser focusing condition for laser-beam interaction in the correction undulator. The amplification factor and the output peak power of the laser amplifier are found to differ substantially from earlier publications. The required power is large for hadron colliders at very high energy.
K.Y. Ng, S.Y. Lee and Y.K. Zhang
Boise geothermal district heating system
This document describes the Boise geothermal district heating project from preliminary feasibility studies completed in 1979 to a fully operational system by 1983. The report includes information about the two local governments that participated in the project - the City of Boise, Idaho and the Boise Warm Springs Water District. It also discusses the federal funding sources; the financial studies; the feasibility studies conducted; the general system planning and design; design of detailed system components; the legal issues involved in production; geological analysis of the resource area; distribution and disposal; the program to market system services; and the methods of retrofitting buildings to use geothermal hot water for space heating. Technically this report describes the Boise City district heating system based on 170/sup 0/F water, a 4000 gpm production system, a 41,000 foot pipeline system, and system economies. Comparable data are also provided for the Boise Warm Springs Water District. 62 figs., 31 tabs.
Hanson, P.J.
Thunderstorms over the Kanto District.
The research is a synthetic report on the thunderstorms over the Kanto District, Japan, containing statistical surveys of thunderstorms, the results of special observations of thunderstorms, radar studies of thunderstorms, cloud seeding experiments and th...
H. Hatakeyama S. Kitazawa H. Nojima
Engineer Profiles: The District Engineer.
This series of four annual interviews with Colonel William W. Badger presents the changing viewpoints of an incumbant District Engineer. The conversations cover a wide range of subjects from the civil works planning process to personnel management. Over t...
F. N. Schubert
Coal Heating District Heating Plants.
The Elektrisitetsforsyningens Forskningsinstitutt (EFI) has considered the Norwegian district heating potential. The remaining demand is 7 TWh and parts of it may be covered by coal when local energy resources are utilized to a reasonable extent. Two plan...
J. Hustad G. Syvertsen P. Walde
Quality Circles for School Districts.
Discusses the applicability of quality circles in schools. Examines elements of a successful quality circle program, the decision to have such a program, establishing quality circles, potential problems, and the use of quality circles in school districts. (CT)
Zahra, Shaker A.; And Others
In-situ study on cooling effect of the two-phase closed thermosyphon and insulation combinational embankment of the Qinghai�Tibet Railway
Based on the observation data of the two-phase closed thermosyphon and insulation combinational test embankment of the Qinghai�Tibet Railway, variations of permafrost table, thermal regime changes, heat budget and heat exchange of the combinational embankment were analyzed. As control groups, natural ground and a traditional soil embankment were also analyzed. Considering thermal asymmetry in the north and the south slopes,
Junjie Wu; Wei Ma; Zhizhong Sun; Zhi Wen
Moorhead District Heating Project. Reference design, Executive Summary
The main source of heat for the proposed Moorhead District Heating system is the municipal power plant which is located along the Red River. The facility has four lignite boilers and one gas fired turbine for emergency power. The capacity and boiler specifications of the lignite boilers are shown. The four lignite boilers have capacity sufficient for all five previously proposed phases of development with the older three boilers sufficient for phases 1 and 2.
Two-phase flow in high-heat-flux micro-channel heat sink for refrigeration cooling applications: Part II�heat transfer characteristics
This paper is the second of a two-part study concerning two-phase flow and heat transfer characteristics of R134a in a micro-channel heat sink incorporated as an evaporator in a refrigeration cycle. Boiling heat transfer coefficients were measured by controlling heat flux (q?=15.9?93.8W\\/cm2) and vapor quality (xe=0.26?0.87) over a broad range of mass velocity. While prior studies point to either nucleate
ICOOL: a simulation code for ionization cooling of muon beams
Current ideas for designing a high luminosity muon collider require significant cooling of the phase space of the muon beams. The only known method that can cool the beams in a time comparable to the muon lifetime is ionization cooling. This method requires directing the particles in the beam at a large angle through a low Z absorber material in
R. C. Fernow
JT-60SA TF Coil Testing Cooling Prevision
The JT-60SA Toroidal Field coil design has been modified resulting in considerable material savings. The casing cooling loop is important during the beginning of cooldown. This study models the cooling phase foreseen for coil testing and coil operation. Data and experience gathered during the extensive cooling tests performed on 70 large W7-X coils at the CEA (Saclay) cryomagnetic test facility
Bertrand Renard; Laurent Genini; Jean-Luc Duchateau
77 FR 16828 - Turlock Irrigation District, & Modesto Irrigation District; Notice of Dispute Resolution Process...
...Hydroelectric Project Project No. 2299-075] Turlock Irrigation District, & Modesto Irrigation District; Notice of Dispute Resolution Process...Hydroelectric Project No. 2299-075.\\1\\ Turlock Irrigation District and the Modesto Irrigation...
77 FR 5507 - Turlock Irrigation District, Modesto Irrigation District; Notice of Proposed Restricted Service...
...Commission [Project No. 2299-075] Turlock Irrigation District, Modesto Irrigation District; Notice of Proposed Restricted Service...into any Order issuing a license. Turlock Irrigation District and Modesto Irrigation...
78 FR 37538 - Idaho Irrigation District; New Sweden Irrigation District; Notice of Preliminary Permit...
...Commission [Project No. 14513-000] Idaho Irrigation District; New Sweden Irrigation District; Notice of Preliminary Permit Application...April 19, 2013, the Idaho and New Sweden Irrigation Districts, filed a joint application for...
77 FR 4291 - Turlock Irrigation District; Modesto Irrigation District; Notice of Proposed Restricted Service...
...Commission [ Project No. 2299-075] Turlock Irrigation District; Modesto Irrigation District; Notice of Proposed Restricted Service...into any Order issuing a license. Turlock Irrigation District and Modesto Irrigation...
75 FR 43958 - Turlock Irrigation District and Modesto Irrigation District; Notice of Application for Amendment...
...Commission [Project No. 2299-074] Turlock Irrigation District and Modesto Irrigation District; Notice of Application for Amendment...Filed: May 24, 2010. d. Applicant: Turlock Irrigation District and Modesto Irrigation...
78 FR 3892 - Turlock Irrigation District and Modesto Irrigation District; Notice Clarifying Party Status
...No. UL11-1-000; Project No. 2299-078] Turlock Irrigation District and Modesto Irrigation District; Notice Clarifying Party Status On January 9, 2013, the Modesto Irrigation District (Modesto) filed a motion for clarification...
Evidence of the existence of the high-density and low-density phases in deeply-cooled confined heavy water under high pressures.
The average density of D2O confined in a nanoporous silica matrix (MCM-41-S) is studied with neutron scattering. We find that below ?210 K, the pressure-temperature plane of the system can be divided into two regions. The average density of the confined D2O in the higher-pressure region is about 16% larger than that in the lower-pressure region. These two regions could represent the so-called "low-density liquid" and "high-density liquid" phases. The dividing line of these two regions, which could represent the associated 1st order liquid-liquid transition line, is also determined. PMID:25005293
Wang, Zhe; Liu, Kao-Hsiang; Harriger, Leland; Le�o, Juscelino B; Chen, Sow-Hsin
Two-phase flow in high-heat-flux micro-channel heat sink for refrigeration cooling applications: Part I��pressure drop characteristics
Two-phase pressure drop was measured across a micro-channel heat sink that served as an evaporator in a refrigeration cycle. The micro-channels were formed by machining 231?m wide�713?m deep grooves into the surface of a copper block. Experiments were performed with refrigerant R134a that spanned the following conditions: inlet pressure of Pin=1.44�6.60bar, mass velocity of G=127�654kg\\/m2s, inlet quality of xe,in=0.001�0.25, outlet
Reno Industrial Park geothermal district heating system
Ten miles south of Reno, on U.S. 395 near the junction of the road to historic Virginia City, is Steamboat Hot Springs, a popular stop for travelers since the mid-1800s. Legend has it that Mark Twain named the geothermal area because it looked and sounded like a chugging Mississippi River paddle-wheeler. It is said when he first saw the steam rising from the ground he exclaimed, {open_quotes}Behold! A Steamboat in the desert.{close_quotes} Over the years, the area has been used for its relaxing and curative qualities by Indians, settlers, and geothermal experts. Since the mid-1980s five geothermal power plants have been built at Steamboat Springs and in December 1996 it was announced that the proposed largest geothermal district heating system in the U.S. would supply an industrial park in the area. The active geothermal area is located within the north-south trending graben like trough between the Carson and Virginia Ranges at the southern end of Truckee Meadows. Hot springs and other geothermal features occur over an area of about one square mile. The mid-basin location is controlled by faulting more or less parallel to the major mountain-front faults. It is believed that the heat source for the system is a cooling magmatic body at depth. The Steamboat geothermal area consists of a deep, high-temperature (215{degrees}C to 240{degrees} C) geothermal system, a shallower, moderate-temperature (160{degrees}C to 18{degrees} C) system, and a number of shallow low-temperature (30{degrees}C to 80{degrees}C) subsystems. The higher temperature systems are used for electric-power generation. It is proposed that the exit fluids from the electric power plants be used for the geothermal district heating system.
Lienau, P.J.
Plugging of cooling holes in film-cooled turbine vanes
The plugging of vane cooling holes by impurities in a marine gas turbine was closely simulated in burner rig tests where dopants were added to the combustion products of a clean fuel (Jet-A). Hole plugging occurred when liquid phases, resulting from the dopants, were present in the combustion products. Increasing flame temperature and dopant concentration resulted in an increased rate of deposition and hole plugging.
Deadmore, D. L.; Lowell, C. E.
Restaurant food cooling practices.
Improper food cooling practices are a significant cause of foodborne illness, yet little is known about restaurant food cooling practices. This study was conducted to examine food cooling practices in restaurants. Specifically, the study assesses the frequency with which restaurants meet U.S. Food and Drug Administration (FDA) recommendations aimed at reducing pathogen proliferation during food cooling. Members of the Centers for Disease Control and Prevention's Environmental Health Specialists Network collected data on food cooling practices in 420 restaurants. The data collected indicate that many restaurants are not meeting FDA recommendations concerning cooling. Although most restaurant kitchen managers report that they have formal cooling processes (86%) and provide training to food workers on proper cooling (91%), many managers said that they do not have tested and verified cooling processes (39%), do not monitor time or temperature during cooling processes (41%), or do not calibrate thermometers used for monitoring temperatures (15%). Indeed, 86% of managers reported cooling processes that did not incorporate all FDA-recommended components. Additionally, restaurants do not always follow recommendations concerning specific cooling methods, such as refrigerating cooling food at shallow depths, ventilating cooling food, providing open-air space around the tops and sides of cooling food containers, and refraining from stacking cooling food containers on top of each other. Data from this study could be used by food safety programs and the restaurant industry to target training and intervention efforts concerning cooling practices. These efforts should focus on the most frequent poor cooling practices, as identified by this study. PMID:23212014
Brown, Laura Green; Ripley, Danny; Blade, Henry; Reimann, Dave; Everstine, Karen; Nicholas, Dave; Egan, Jessica; Koktavy, Nicole; Quilliam, Daniela N
Debuncher cooling performance
We present measurements of the Fermilab Debuncher momentum and transverse cooling systems. These systems use liquid helium cooled waveguide pickups and slotted waveguide kickers covering the frequency range 4-8 GHz.
Derwent, P.F.; McGinnis, David; Pasquinelli, Ralph; Vander Meulen, David; Werkema, Steven; /Fermilab
Debuncher Cooling Performance
Derwent, P. F.; McGinnis, David; Pasquinelli, Ralph; Vander Meulen, David; Werkema, Steven [Fermi National Accelerator Laboratory, P. O. Box 500, Batavia IL 60510-0500 (United States)
Liquid-Cooled Garment
A liquid-cooled bra, offshoot of Apollo moon suit technology, aids the cancer-detection technique known as infrared thermography. Water flowing through tubes in the bra cools the skin surface to improve resolution of thermograph image.
Ultrasonic Convection Cooling.
The report discusses an investigation of ultrasonic cooling techniques. Natural and forced convective cooling parameters were measured, with and without the application of ultrasonic agitation. It was experimentally determined that application of the tech...
J. E. McCormick T. W. Walsh
Radial turbine cooling
The technology of high temperature cooled radial turbines is reviewed. Aerodynamic performance considerations are described. Heat transfer and structural analysis are addressed, and in doing so the following topics are covered: cooling considerations, hot side convection, coolant side convection, and rotor mechanical analysis. Cooled rotor concepts and fabrication are described, and the following are covered in this context: internally cooled rotor, hot isostatic pressure bonded rotor, laminated rotor, split blade rotor, and the NASA radial turbine program.
Roelke, Richard J.
Cooling of Stored Beams
Beam cooling methods developed for the accumulation of antiprotons are being employed to assist in the performance of experiments in Nuclear and Particle Physics with ion beams stored in storage rings. The physics of beam cooling, and the ranges of utility of stochastic and electron cooling are discussed in this paper.
Mills, F.
Stochastic cooling in RHIC
After the success of longitudinal stochastic cooling of bunched heavy ion beam in RHIC, transverse stochastic cooling in the vertical plane of Yellow ring was installed and is being commissioned with proton beam. This report presents the status of the effort and gives an estimate, based on simulation, of the RHIC luminosity with stochastic cooling in all planes.
Brennan,J.M.; Blaskiewicz, M. M.; Severino, F.
Modular District Heating System MODiS.
MODiS (Modular District Heating System) products were developed during the project for either building an entirely new district heating (DH) system or for renovating and extending an existing system. Good planning of the parts that constitute DH systems, ...
K. Sipilae A. Ranne T. Koljonen
A Computational Prototype of Industrial District
The aim of our paper is to suggest an agent-based computational approach to industrial districts. Agent-based computational techniques enable us to focus industrial district modeling on evolutionary fundamentals, such as \\
Riccardo Boero; Flaminio Squazzoni
7 CFR 966.24 - Districts.
...Osceola, Okeechobee, Palm Beach, and St. Lucie in the State of Florida; District No. 3. The counties of Charlotte, Collier, Hendry, Lee, and Monroe in the State of Florida; and District No. 4. The counties of De Soto, Hardee,...
The Cool Flames Experiment
A space-based experiment is currently under development to study diffusion-controlled, gas-phase, low temperature oxidation reactions, cool flames and auto-ignition in an unstirred, static reactor. At Earth's gravity (1g), natural convection due to self-heating during the course of slow reaction dominates diffusive transport and produces spatio-temporal variations in the thermal and thus species concentration profiles via the Arrhenius temperature dependence of the reaction rates. Natural convection is important in all terrestrial cool flame and auto-ignition studies, except for select low pressure, highly dilute (small temperature excess) studies in small vessels (i.e., small Rayleigh number). On Earth, natural convection occurs when the Rayleigh number (Ra) exceeds a critical value of approximately 600. Typical values of the Ra, associated with cool flames and auto-ignitions, range from 104-105 (or larger), a regime where both natural convection and conduction heat transport are important. When natural convection occurs, it alters the temperature, hydrodynamic, and species concentration fields, thus generating a multi-dimensional field that is extremely difficult, if not impossible, to be modeled analytically. This point has been emphasized recently by Kagan and co-workers who have shown that explosion limits can shift depending on the characteristic length scale associated with the natural convection. Moreover, natural convection in unstirred reactors is never "sufficiently strong to generate a spatially uniform temperature distribution throughout the reacting gas." Thus, an unstirred, nonisothermal reaction on Earth does not reduce to that generated in a mechanically, well-stirred system. Interestingly, however, thermal ignition theories and thermokinetic models neglect natural convection and assume a heat transfer correlation of the form: q=h(S/V)(T(bar) - Tw) where q is the heat loss per unit volume, h is the heat transfer coefficient, S/V is the surface to volume ratio, and (T(bar) - Tw ) is the spatially averaged temperature excess. This Newtonian form has been validated in spatially-uniform, well-stirred reactors, provided the effective heat transfer coefficient associated with the unsteady process is properly evaluated. Unfortunately, it is not a valid assumption for spatially-nonuniform temperature distributions induced by natural convection in unstirred reactors. "This is why the analysis of such a system is so difficult." Historically, the complexities associated with natural convection were perhaps recognized as early as 1938 when thermal ignition theory was first developed. In the 1955 text "Diffusion and Heat Exchange in Chemical Kinetics", Frank-Kamenetskii recognized that "the purely conductive theory can be applied at sufficiently low pressure and small dimensions of the vessel when the influence of natural convection can be disregarded." This was reiterated by Tyler in 1966 and further emphasized by Barnard and Harwood in 1974. Specifically, they state: "It is generally assumed that heat losses are purely conductive. While this may be valid for certain low pressure slow combustion regimes, it is unlikely to be true for the cool flame and ignition regimes." While this statement is true for terrestrial experiments, the purely conductive heat transport assumption is valid at microgravity (mu-g). Specifically, buoyant complexities are suppressed at mu-g and the reaction-diffusion structure associated with low temperature oxidation reactions, cool flames and auto-ignitions can be studied. Without natural convection, the system is simpler, does not require determination of the effective heat transfer coefficient, and is a testbed for analytic and numerical models that assume pure diffusive transport. In addition, mu-g experiments will provide baseline data that will improve our understanding of the effects of natural convection on Earth.
Pearlman, Howard; Chapek, Richard; Neville, Donna; Sheredy, William; Wu, Ming-Shin; Tornabene, Robert
Cooling apparatus for water-cooled engines
A cooling apparatus is described for a water-cooled internal combustion engine including a shaft that rotates when the engine is running, the apparatus comprising a centrifugal fan adapted to be connected to and rotated by the shaft, the fan having an intake air port and a discharge air opening, a rotary screen adapted to be operatively connected to and rotated by the shaft, the screen being disposed in the intake air port, a cooling radiator, a spiral-shaped duct connecting the radiator with the discharge air opening, and separating means on the duct, the separating means comprising an opening formed in the outer wall of the duct.
Fujikawa, T.; Tamba, S.
Alternatives to School District Consolidation.
Consolidation has become both a solution for small, rural school districts and a contentious policy fraught with numerous difficulties. Despite concerns about limited curricula and higher operating expenses, there is no generalizable evidence that students educated in rural settings underachieve or have deficient social skills. Recent research has�
Berliner, Bethann
Sharpening a District's Leadership Model
To create an integrated board self-assessment and superintendent evaluation process, district leaders must develop a school leadership model by adopting a coherent governance model. At the same time, they must also develop goals at the appropriate level that ensure quality governance of a school system. In the second of a two-part series, the�
Namit, Chuck
Spatial Planning of School Districts
The development of several plans based on linear programming and geographic methodology will permit school administrators to make better decisions concerning the planning of school districts: where to locate boundaries, how to eliminate overcrowding, where to locate new classrooms, and how to overcome de facto segregation. The primal and dual�
Maxfield, Donald W.
Forecasting School District Fiscal Health.
This paper's goal is to redefine fiscal health by broadening its predictive function and to determine which fiscal indicators are useful for forecasting fiscal health for one, two, and three years. Results indicate that school district fiscal health forecasts are potentially great planning tools for local for local decision makers. Includes 11�
Smith, Curtis A.
Districts Created to Steer "Turnarounds"
If the job of a traditional superintendent is hard, imagine the complexities involved in building a school system from scratch--especially one composed of schools with some of the most intractable educational challenges. That's the task facing education leaders in Michigan and Tennessee, which are building special districts to take over�
Samuels, Christina A.
Nuclear Power for District Heating.
Current district heating trends are towards an increasing use of electricity. The evaluation of an alternative means of energy supply, the direct use of thermal energy from CANDU nuclear stations, is described. The energy would be transmitted via a hot fl...
R. B. Lyon R. O. Sochaski
District Considerations in Math Modeling.
The primary purpose of this paper is to provide some guidance for proper selection of a math model for application at the District level. The secondary purpose of this paper is to assure those interested in math modeling that the task is not formidable. T...
R. E. Punnett
Nation, Districts Step up Safety
President Barack Obama's announcement last week of a wide-ranging anti-violence plan in response to the Newtown, Connecticut, school shootings comes as many districts are adopting new and sometimes dramatic measures--including arming teachers and volunteers--intended to prevent similar tragedies in their own schools. School safety experts warn�
Increasing Black Student Enrollment in Gifted Programs: An Exploration of the Pulaski County Special School District's Advocacy Efforts.
Results are presented of an advocacy event in Pulaski County, Arkansas, where one school district's efforts to desegregate their gifted program resulted in more black students enrolled. Different phases of a Gifted Program Advocacy Model are used to explain important components of the Pulaski County Special School District's advocacy efforts.�
Grantham, Tarek C.
Survey of Burglary and Vandalism Occurrence and Preventative Measures in Twenty-Five Large California School Districts. Summary Report.
Twenty-three California school districts responded to a burglary and vandalism survey conducted by the Fresno Unified School District Burglary and Vandalism Prevention Project, which represents the first phase of a developing program to reduce vandalism occurrences and improve recovery of losses. This summary compiles survey data on 18,000�
Fresno City Unified School District, CA. Office of Planning and Research Services.
What Do Unauthorized Absences Cost the District?
THE FOLLOWING IS THE FULL TEXT OF THIS DOCUMENT: For each student day of unauthorized student absence, the district loses $11.95. Last year there were 95,818 student days of unauthorized absence for which the district did not receive any money from the state. This represented a loss to the district of $1,145,025. These appear to be staggering�
Superintendent's Communicator, 1982
Windham County Natural Resources Conservation District
The Windham County Natural Resources Conservation District was authorized and formed by the State of Vermont on January 8, 1946, under the provisions of the Soil Conservation Act No. 246 of the Acts of the 1939 Vermont General Assembly. It is one of 14 Conservation Districts in the state of Vermont. Windham District is a political subdivision of the State
Vice Chairperson; Gail MacArthur; Andrea Darrow
District Learning Tied to Student Learning
Winners and finalists for the annual Broad Prize for Urban Education have consistently outperformed peer districts serving similar student populations. What makes the difference? These districts consistently demonstrate a learning loop that influences the district's ability to learn, which ultimately influences student opportunities to learn.�
McFadden, Ledyard
School District Effects and Efficiency. Special Report.
This paper describes efforts to develop indices of student achievement, school district effort, and school district efficiency. The challenge was to develop measures that are simple to understand, yet allow comparison among districts that are not distorted by socioeconomic differences. Measures were developed for average student achievement,�
Swanson, Austin D.; Engert, Frank
School District Consolidation: The Benefits and Costs
School district consolidation is a striking phenomenon. According to the National Center for Education Statistics, 117,108 school districts provided elementary and secondary education in 1939-1940. By 2006-2007, the number of districts had dropped to 13,862, a decline of 88 percent. The rate of consolidation has slowed in recent years, but at�
Duncombe, William D.; Yinger, John M.
Cooling water distribution system
A passive containment cooling system for a nuclear reactor containment vessel. Disclosed is a cooling water distribution system for introducing cooling water by gravity uniformly over the outer surface of a steel containment vessel using an interconnected series of radial guide elements, a plurality of circumferential collector elements and collector boxes to collect and feed the cooling water into distribution channels extending along the curved surface of the steel containment vessel. The cooling water is uniformly distributed over the curved surface by a plurality of weirs in the distribution channels.
Orr, Richard (Pittsburgh, PA)
A large-scale test of dry\\/wet cooling using the ammonia phase-change system, designated the Advanced Concepts Test (ACT), has been operated at Pacific Gas and Electric Company's Kern Station at Bakersfield, California. The facility is capable of condensing 60,000 lbs\\/h of steam from a small house turbine. Two different modes of combining dry and evaporative cooling have been tested. One uses
R. T. Allemann; D. E. DeBellis; E. V. Werry; B. M. Johnson
Potential Refrigerants for Power Electronics Cooling
In the past, automotive refrigerants have conventionally been used solely for the purpose of air conditioning. However, with the development of hybrid-electric vehicles and the incorporation of power electronics (PEs) into the automobile, automotive refrigerants are taking on a new role. Unfortunately, PEs have lifetimes and functionalities that are highly dependent on temperature and as a result thermal control plays an important role in the performance of PEs. Typically, PEs are placed in the engine compartment where the internal combustion engine (ICE) already produces substantial heat. Along with the ICE heat, the additional thermal energy produced by PEs themselves forces designers to use different cooling methods to prevent overheating. Generally, heat sinks and separate cooling loops are used to maintain the temperature. Disturbingly, the thermal control system can consume one third of the total volume and may weigh more than the PEs [1]. Hence, other avenues have been sought to cool PEs, including submerging PEs in automobile refrigerants to take advantage of two-phase cooling. The objective of this report is to explore the different automotive refrigerants presently available that could be used for PE cooling. Evaluation of the refrigerants will be done by comparing environmental effects and some thermo-physical properties important to two-phase cooling, specifically measuring the dielectric strengths of potential candidates. Results of this report will be used to assess the different candidates with good potential for future use in PE cooling.
Starke, M.R.
The MANX Muon Cooling Experiment Detection System
The MANX experiment is being proposed to demonstrate the reduction of 6D muon phase space emittance, using a continuous liquid absorber to provide ionization cooling in a helical solenoid magnetic channel. The experiment involves the construction of a two-period-long helical cooling channel (HCC) to reduce the muon invariant emittance by a factor of two. The HCC would replace the current cooling section of the MICE experiment now being set up at the Rutherford Appleton Laboratory. The MANX experiment would use the existing MICE spectrometers and muon beam line. We discuss the placement of detection planes to optimize the muon track resolution.
Kahn, S. A.; Abrams, R. J.; Ankenbrandt, C.; Cummings, M. A. C.; Johnson, R. P.; Robertsa, T. J.; Yoneharab, K.
Principles and applications of muon cooling
The basic principles of the application of {open_quote}{open_quote}ionization cooling{close_quote}{close_quote} to obtain high phase-space density muon beams are described, and its limitations are outlined. Sample cooling scenarios are presented. Applications of cooled muon beams in high-energy accelerators are suggested; high-luminosity {mu}{sup +}{minus}{mu}{sup {minus}} and {mu}{minus}{ital p} colliders at {approx_gt}1-TeV energy are possible. {copyright} {ital 1995 American Institute of Physics.}
Neuffer, D. [Los Alamos National Laboratory, Los Alamos, New Mexico 67545 (United States)
Environmental Assessment of Cooling Reservoirs.
The environmental impacts, both adverse and beneficial, of cooling reservoirs are compared to cooling towers as an alternative closed cycle cooling system. Generally, the impacts associated with the construction of a cooling reservoir system are greater t...
B. R. Parkhurst H. A. McLain
We discuss particle tracking simulations in a storage ring with lithium lens inserts designed for the six-dimensional phase space cooling of muons by the ionization cooling. The ring design contains one or more lithium lens absorbers for transverse cooling that transmit the beam with very small beta-function values, in addition to liquid-hydrogen wedge-shaped absorbers in dispersive locations for longitudinal cooling. Such a ring could comprise the final component of a cooling system for use in a muon collider. The beam matching between dipole-quadrupole lattices and the lithium lenses is of particular interest.
Memory coherence of a sympathetically cooled trapped-ion qubit
We demonstrate sympathetic cooling of a C43a+ trapped-ion �memory� qubit by a C40a+ �coolant� ion sufficiently near the ground state of motion for fault-tolerant quantum logic, while maintaining coherence of the qubit. This is an essential ingredient in trapped-ion quantum computers. The isotope shifts are sufficient to suppress decoherence and phase shifts of the memory qubit due to the cooling light which illuminates both ions. We measure the qubit coherence during ten cycles of sideband cooling, finding a coherence loss of 3.3% per cooling cycle. The natural limit of the method is O(10-4) infidelity per cooling cycle.
Home, J. P.; McDonnell, M. J.; Szwer, D. J.; Keitch, B. C.; Lucas, D. M.; Stacey, D. N.; Steane, A. M.
Geothermal district piping - A primer
Transmission and distribution piping constitutes approximately 40 -60% of the capital costs of typical geothermal district heating systems. Selections of economical piping suitable for the fluid chemistry is critical. Presently, most piping (56%) in geothermal systems is of asbestos cement construction. Some fiberglass (19%) and steel (19%) is also in use. Identification of an economical material to replace asbestos cement is important to future project development. By providing information on relative costs, purchase considerations, existing material performance and new products, this report seeks to provide a background of information to the potential pipe purchaser. A brief discussion of the use of uninsulated piping in geothermal district heating systems is also provided. 5 refs., 19 figs., 1 tab.
Rafferty, K.
Gas turbine cooling system
A gas turbine engine (10) having a closed-loop cooling circuit (39) for transferring heat from the hot turbine section (16) to the compressed air (24) produced by the compressor section (12). The closed-loop cooling system (39) includes a heat exchanger (40) disposed in the flow path of the compressed air (24) between the outlet of the compressor section (12) and the inlet of the combustor (14). A cooling fluid (50) may be driven by a pump (52) located outside of the engine casing (53) or a pump (54) mounted on the rotor shaft (17). The cooling circuit (39) may include an orifice (60) for causing the cooling fluid (50) to change from a liquid state to a gaseous state, thereby increasing the heat transfer capacity of the cooling circuit (39).
Bancalari, Eduardo E. (Orlando, FL)
NASA Microclimate Cooling Challenges
The purpose of this outline form presentation is to present NASA's challenges in microclimate cooling as related to the spacesuit. An overview of spacesuit flight-rated personal cooling systems is presented, which includes a brief history of cooling systems from Gemini through Space Station missions. The roles of the liquid cooling garment, thermal environment extremes, the sublimator, multi-layer insulation, and helmet visor UV and solar coatings are reviewed. A second section is presented on advanced personal cooling systems studies, which include heat acquisition studies on cooling garments, heat rejection studies on water boiler & radiators, thermal storage studies, and insulation studies. Past and present research and development and challenges are summarized for the advanced studies.
Trevino, Luis A.
Swedish district heating using fuelwood
The Swedish government uses monetary incentives to increase the use of biomass in the energy sector in an attempt to reduce carbon dioxide emissions. This paper reports on the use of wood fuel for district heating in Sweden and describe a project which was the recipient of a government subsidy. This project is the first wood fired IGCC power plant in the world and has lead the way for the commercial scale demonstration plant in Brazil described in a previous paper.
Palmberger, B.; Olofsson, K. [NUTEK, Stockholm (Sweden)
S'COOL Flyer
This flyer is a two-page overview of the Student Cloud Observations On-Line (S'COOL) education project. It covers the project's educational contributions, societal benefits, educational outgrowths, and scientific findings. The flyer shows the numbers and locations of S'COOL participation and regional observation coverage. It also contains URLs for online resources (e.g., GLOBE contrail education and S-COOL Website).
Kanyakumari district accepts family planning.
The people of Kanyakumari District known for their die-hard conservatism, finally seem to have taken to family planning as a way of life. This is borne out by the overwhelming support extended by them to the tubectomy camp organized by the District Family Planning Bureau, Kanyakumari, from 22nd to 27th February 1972. The target of 300 operations set for the camp was exceeded by 99. This is a significant achievement considering the fact that the district consists of only 9 Panchayat Unions covering a vast coastal area with a population of over 1/2 lakhs which is mainly engaged in the fishing industry and is generally not in favor of family planning. The camp provided free food and transport facilities to the patient and the person attending her and a monetary incentive of Rs. 30 per case, besides post-operational care which included periodical home visits by the staff of the Public Health Center for over 3 months. Administration of Vitamin A solution and immunisation of the children of the acceptors and their neighbors constituted an additional feature of this campaign. The effort made by the staff of the Family Planning Department, the Maternity Assistants of the Headquarters Hospital, Nagercoil, where the camp was held, and the Field Publicity Department of the Government of India, were responsible for the success of this campaign. PMID:12332926
Central Utah Water Conservancy District
The Central Utah Water Conservancy District (CUWCD) is a political subdivision of the State of Utah. It was formally established in 1964 to act as the local entity to contract with the United States of America in connection with the construction, operation, and financing of the Central Utah Project (CUP). The purpose of the CUP is to enable the State of Utah to beneficially use a substantial portion of its allotted share of the Colorado River water under the Colorado River Compact. The District sponsors the CUP which includes five specific units. Each unit consists of a series of dams, pipelines, reservoirs, tunnels, and aqueducts designed to assist in meeting the water needs of all ten counties through approximately the year 2020. The District, primarily a wholesaler of water to other cities and agencies, has the responsibility to plan, design, construct, operate and maintain project facilities, administer the sale and delivery of project water, and repay the federal government the reimbursable costs of the CUP.
Hydrogen film cooling investigation
Effects of flow turning, flow acceleration, and supersonic flow on film cooling were determined experimentally and correlated in terms of an entrainment film cooling model. Experiments were conducted using thin walled metal test sections, hot nitrogen mainstream gas, and ambient hydrogen or nitrogen as film coolants. The entrainment film cooling model relates film cooling effectiveness to the amount of mainstream gases entrained with the film coolant in a mixing layer. The experimental apparatus and the analytical model used are described in detail and correlations for the entrainment fraction and film coolant-to-wall heat transfer coefficient are presented.
Rousar, D. C.; Ewen, R. L.
Power electronics cooling apparatus
A semiconductor cooling arrangement wherein a semiconductor is affixed to a thermally and electrically conducting carrier such as by brazing. The coefficient of thermal expansion of the semiconductor and carrier are closely matched to one another so that during operation they will not be overstressed mechanically due to thermal cycling. Electrical connection is made to the semiconductor and carrier, and a porous metal heat exchanger is thermally connected to the carrier. The heat exchanger is positioned within an electrically insulating cooling assembly having cooling oil flowing therethrough. The arrangement is particularly well adapted for the cooling of high power switching elements in a power bridge.
Sanger, Philip Albert (Monroeville, PA); Lindberg, Frank A. (Baltimore, MD); Garcen, Walter (Glen Burnie, MD)
Sanger, P.A.; Lindberg, F.A.; Garcen, W.
Volcanoes and Global Cooling
Volcanic eruptions are thought to be responsible for the global cooling that has been observed for a few years after a major eruption. The amount and global extent of the cooling depend on the force of the eruption and, possibly, its latitude. When large masses of gases from the eruption reach the stratosphere, they can produce a large, widespread cooling effect. As a prime example, the effects of Mount Pinatubo, which erupted in June 1991, may have lasted a few years, serving to offset temporarily the predicted greenhouse effect. This site describes the phenomenon of volcanic global cooling and NASA's instruments and missions to study it.
Passive containment cooling system
A containment cooling system utilizes a naturally induced air flow and a gravity flow of water over the containment shell which encloses a reactor core to cool reactor core decay heat in two stages. When core decay heat is greatest, the water and air flow combine to provide adequate evaporative cooling as heat from within the containment is transferred to the water flowing over the same. The water is heated by heat transfer and then evaporated and removed by the air flow. After an initial period of about three to four days when core decay heat is greatest, air flow alone is sufficient to cool the containment.
Conway, Lawrence E. (Robinson Township, Allegheny County, PA); Stewart, William A. (Penn Hills Township, Allegheny County, PA)
Semioptimal practicable algorithmic cooling
Algorithmic cooling (AC) of spins applies entropy manipulation algorithms in open spin systems in order to cool spins far beyond Shannon�s entropy bound. Algorithmic cooling of nuclear spins was demonstrated experimentally and may contribute to nuclear magnetic resonance spectroscopy. Several cooling algorithms were suggested in recent years, including practicable algorithmic cooling (PAC) and exhaustive AC. Practicable algorithms have simple implementations, yet their level of cooling is far from optimal; exhaustive algorithms, on the other hand, cool much better, and some even reach (asymptotically) an optimal level of cooling, but they are not practicable. We introduce here semioptimal practicable AC (SOPAC), wherein a few cycles (typically two to six) are performed at each recursive level. Two classes of SOPAC algorithms are proposed and analyzed. Both attain cooling levels significantly better than PAC and are much more efficient than the exhaustive algorithms. These algorithms are shown to bridge the gap between PAC and exhaustive AC. In addition, we calculated the number of spins required by SOPAC in order to purify qubits for quantum computation. As few as 12 and 7 spins are required (in an ideal scenario) to yield a mildly pure spin (60% polarized) from initial polarizations of 1% and 10%, respectively. In the latter case, about five more spins are sufficient to produce a highly pure spin (99.99% polarized), which could be relevant for fault-tolerant quantum computing.
Elias, Yuval; Mor, Tal; Weinstein, Yossi
Heating and cooling
Heating and cooling homes and businesses require a major energy commitment. This informational piece, part of a series about the future of energy, introduces students to the energy needed to heat and cool homes and workplaces. Students explore energy requirements in the home and at work and discuss current technologies to improve heating and cooling efficiencies. Articles on heat pumps and solar heating and cooling techniques are accessible from a sidebar. A link to a PBS NewsHour article on air conditioning efficiency and a link to material discussing alternatives to air conditioning are also provided. Copyright 2005 Eisenhower National Clearinghouse
Project, Iowa P.
Coherent Electron Cooling
Cooling intense high-energy hadron beams poses a major challenge for modern accelerator physics. The synchrotron radiation emitted from such beams is feeble; even in the Large Hadron Collider (LHC) operating with 7 TeV protons, the longitudinal damping time is about 13 hours. None of the traditional cooling methods seem able to cool LHC-class protons beams. In this Letter, we present a novel method of coherent electron cooling based on a high-gain free-electron laser (FEL). This technique could be critical for reaching high luminosities in hadron and electron-hadron colliders.
Litvinenko, Vladimir N. [Brookhaven National Laboratory, Upton, Long Island, New York (United States); Derbenev, Yaroslav S. [Thomas Jefferson National Accelerator Facility, Newport News, Virginia (United States)
Asthma, airways responsiveness and air pollution in two contrasting districts of northern England
BACKGROUND: To assess the possible magnitude of differences between normal populations an epidemiological investigation of asthma was conducted in two strongly contrasting districts of northern England--rural West Cumbria on the west coast and urban Newcastle upon Tyne on the east coast. METHODS: A cross sectional survey of randomly identified men aged 20-44 years was conducted in two phases: phase 1,
G. Devereux; T. Ayatollahi; R. Ward; C. Bromly; S. J. Bourke; S. C. Stenton; D. J. Hendrick
Potential for a cycling steam power plant with TES to supply district heating in Washington DC
The Energy Office of the District of Columbia is planning the conversion of a 1500 TPD incinerator for district heating and the generation of electric power for sale to the local utility, PEPCO. This paper records a preliminary evaluation of whether hot water storage would be appropriate at the heat source plant to maximize power sales and improve the reliability of the district heat service. Hot water storage is being employed successfully at Herning, Denmark, in conjunction with a cogeneration plant heat source, and this concept is adapted to Washington D.C. area needs for heating and cooling service. Heat storage allows a 7% increase in power sales based on a simplified approach to daily load profiles and PEPCO's proposed avoided cost rates. Pressurized storage is uneconomic due to the high cost of containment, but atmospheric storage at 200F shows a simple payback of 5 years.
Hobson, M.J.
Understanding School District Budgets: A Guide For Local Leaders
A school district budget is more than numbers. It is a record of a district?s past decisions and a spending plan for its future. It shows a district?s priorities whether they have been clearly articulated or simply occurred by default. And it is a communications document that can tell constituents a lot about the district?s priorities and goals. A�
Perry, Mary
Prospects of laser cooling in atomic thallium
One of the most precisely determined upper limits for the electron electric dipole moment (EDM) is set by the thallium (Tl) atomic beam experiment. One way to enhance the sensitivity of the atomic beam setup is to laser cool the Tl atoms to reduce the EDM-like phase caused by the Exv effect. In this report, a cooling scheme based on the 6P{sub 3/2}(F=2){r_reversible}6D{sub 5/2}(F{sup '}=3) transition in Tl is proposed. The absolute frequency measurement of this nearly closed-cycle transition was performed in an atomic beam apparatus. Two Ti:sapphire lasers were frequency-doubled using enhancement cavities in X-type configurations to provide the needed 377- and 352-nm light sources for the optical pumping and cooling transitions, respectively. The absolute frequency of this cooling transition is determined to be 851 634 646(56) MHz.
Fan, Isaac; Chen, Tzu-Ling; Liu, Yu-Sheng; Lien, Yu-Hung; Liu, Yi-Wei [Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Shy, Jow-Tsong [Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Institute of Photonics Technologies, National Tsing Hua University, Hsinchu 30013, Taiwan (China)
Liquid metal cooled nuclear reactors with passive cooling system
A liquid metal cooled nuclear reactor having a passive cooling system for removing residual heat resulting from fuel decay during reactor shutdown. The passive cooling system comprises a plurality of cooling medium flow circuits which cooperate to remove and carry heat away from the fuel core upon loss of the normal cooling flow circuit to areas external thereto.
Hunsbedt, Anstein (Los Gatos, CA); Fanning, Alan W. (San Jose, CA)
Coherent electron cooling
Cooling intense high-energy hadron beams remains a major challenge in modern accelerator physics. Synchrotron radiation is still too feeble, while the efficiency of two other cooling methods, stochastic and electron, falls rapidly either at high bunch intensities (i.e. stochastic of protons) or at high energies (e-cooling). In this talk a specific scheme of a unique cooling technique, Coherent Electron Cooling, will be discussed. The idea of coherent electron cooling using electron beam instabilities was suggested by Derbenev in the early 1980s, but the scheme presented in this talk, with cooling times under an hour for 7 TeV protons in the LHC, would be possible only with present-day accelerator technology. This talk will discuss the principles and the main limitations of the Coherent Electron Cooling process. The talk will describe the main system components, based on a high-gain free electron laser driven by an energy recovery linac, and will present some numerical examples for ions and protons in RHIC and the LHC and for electron-hadron options for these colliders. BNL plans a demonstration of the idea in the near future.
Ultrasonic convective cooling
This paper discusses an in-the-house research investigation of ultrasonic cooling techniques. Natural and forced convective cooling parameters were measured, with and without the application of ultrasonic agitation. It was experimentally determined that application of the technique resulted in as much as a three fold improvement in heat transfer. Comparisons of the effectiveness of the various modes of agitation were drawn.
J. McCormick; T. Walsh
Cool Earth Solar
In a public-private partnership that takes full advantage of the Livermore Valley Open Campus (LVOC) for the first time, Sandia National Laboratories and Cool Earth Solar have signed an agreement that could make solar energy more affordable and accessible. In this piece, representatives from Sandia, Cool Earth Solar, and leaders in California government all discuss the unique partnership and its expected impact.
Lamkin, Rob; McIlroy, Andy; Swalwell, Eric; Rajan, Kish
Why Cool Roofs?
By installing a cool roof at DOE, the federal government and Secretary Chu are helping to educate families and businesses about the important energy and cost savings that can come with this simple, low-cost technology. Cool roofs have the potential to quickly and dramatically reduce global carbon emissions while saving money every month on consumers' electrical bills.
Chu, Steven
Hot weather days cause often large fresh milk defect in southern developing countries dairy farms as well as in rural areas where there is a scarcity of energy sources that could run cooling equipments. Consequently, the possibility to use solar cooling starts to be considered an attractive solution. The aim of the work presented is to develop an innovative solar
O. Ayadi; J. Doell; M. Aprile; M. Motta; T. N��ez
DOAS, Radiant Cooling Revisited
The article discusses dedicated outdoor air systems (DOAS) and radiant cooling technologies. Both of these topics were covered in previous ASHRAE Journal columns. This article reviews the technologies and their increasing acceptance. The two steps that ASHRAE is taking to disseminate DOAS information to the design community, available energy savings and the market potential of radiant cooling systems are addressed as well.
Hastbacka, Mildred; Dieckmann, John; Bouza, Antonio
Cooling with solar energy
Advantages of an absorption cooling system based on the use of solar energy are partly related to the fact that no long-term storage facilities are needed because the amount of solar energy supplied on a temporal basis corresponds approximately to the energy required for cooling. Other advantages are connected with decentralized application possibilities, the employment of reliable technologies, and high
K. Schubert; J. Dreyer
Cooling Water Systems Module
The Center for the Advancement of Process Technology presents this free sample module on cooling water systems in the process industry. The material includes 21 slides and will help learners understand related terms, the purpose of the basic equipment involved in cooling water systems and the safety, health and environmental concerns involved with these systems.
Surface cooling system
This patent discloses a cooling system for providing a layer of relatively cool gas adjacent the surface of a duct carrying a flow of relatively hot gas. It includes an elongated louver nozzle, an elongated plenum and one or more crosswise dividers for separating the plenum and nozzle into a plurality of individual segments having sized supply orifices disposed therein.
Zimmerman, Anthony M.
Keep it Cool
In this activity, learners explore how engineers have met the challenge of keeping foods, liquids, and other items cool. Learners learn about heat transfer, vacuums, and insulation and design a system to keep a cup of chilled water as cool as possible for one hour. Learners compare their results with that of other learners and reflect on the lesson.
Cooling with night air
Opening the windows at night and closing them during the day is a traditional way to cool an adobe house during the summer in New Mexico. How big the windows should be, where the should be located, and how much hot weather can be tolerated with this cooling scheme is discussed.
Baer, S.
Molecular cooling via Sisyphus processes
We present a study of Sisyphus cooling of molecules: The scattering of a single photon removes a substantial amount of the molecular kinetic energy and an optical pumping step allows one to repeat the process. A review of the produced cold molecules so far indicates that the method can be implemented for most of them, making it a promising method able to produce a large sample of molecules at sub-mK temperatures. Considerations of the required experimental parameters, for instance the laser power and linewidth or the trap anisotropy and dimensionality, are given. Rate equations, as well as scattering and dipolar forces, are solved using kinetic Monte Carlo methods for several lasers and several levels. For NH molecules, such detailed simulation predicts a 1000-fold temperature reduction and an increase of the phase-space density by a factor of 107. Even in the case of molecules with both low Franck-Condon coefficients and a nonclosed pumping scheme, 60% of trapped molecules can be cooled from 100 mK to sub-mK temperatures in a few seconds. Additionally, these methods can be applied to continuously decelerate and cool a molecular beam.
Comparat, Daniel
RHIC stochastic cooling motion control
Relativistic Heavy Ion Collider (RHIC) beams are subject to Intra-Beam Scattering (IBS) that causes an emittance growth in all three-phase space planes. The only way to increase integrated luminosity is to counteract IBS with cooling during RHIC stores. A stochastic cooling system for this purpose has been developed, it includes moveable pick-ups and kickers in the collider that require precise motion control mechanics, drives and controllers. Since these moving parts can limit the beam path aperture, accuracy and reliability is important. Servo, stepper, and DC motors are used to provide actuation solutions for position control. The choice of motion stage, drive motor type, and controls are based on needs defined by the variety of mechanical specifications, the unique performance requirements, and the special needs required for remote operations in an accelerator environment. In this report we will describe the remote motion control related beam line hardware, position transducers, rack electronics, and software developed for the RHIC stochastic cooling pick-ups and kickers.
Gassner, D.; DeSanto, L.; Olsen, R.H.; Fu, W.; Brennan, J.M.; Liaw, CJ; Bellavia, S.; Brodowski, J.
Hydronic rooftop cooling systems
A roof top cooling unit has an evaporative cooling section that includes at least one evaporative module that pre-cools ventilation air and water; a condenser; a water reservoir and pump that captures and re-circulates water within the evaporative modules; a fan that exhausts air from the building and the evaporative modules and systems that refill and drain the water reservoir. The cooling unit also has a refrigerant section that includes a compressor, an expansion device, evaporator and condenser heat exchangers, and connecting refrigerant piping. Supply air components include a blower, an air filter, a cooling and/or heating coil to condition air for supply to the building, and optional dampers that, in designs that supply less than 100% outdoor air to the building, control the mixture of return and ventilation air.
Bourne, Richard C. (Davis, CA) [Davis, CA; Lee, Brian Eric (Monterey, CA) [Monterey, CA; Berman, Mark J. (Davis, CA) [Davis, CA
Water cooled steam jet
A water cooled steam jet for transferring fluid and preventing vapor lock, or vaporization of the fluid being transferred, has a venturi nozzle and a cooling jacket. The venturi nozzle produces a high velocity flow which creates a vacuum to draw fluid from a source of fluid. The venturi nozzle has a converging section connected to a source of steam, a diffuser section attached to an outlet and a throat portion disposed there between. The cooling jacket surrounds the venturi nozzle and a suction tube through which the fluid is being drawn into the venturi nozzle. Coolant flows through the cooling jacket. The cooling jacket dissipates heat generated by the venturi nozzle to prevent vapor lock. 2 figs.
Wagner, E.P. Jr.
A water cooled steam jet for transferring fluid and preventing vapor lock, or vaporization of the fluid being transferred, has a venturi nozzle and a cooling jacket. The venturi nozzle produces a high velocity flow which creates a vacuum to draw fluid from a source of fluid. The venturi nozzle has a converging section connected to a source of steam, a diffuser section attached to an outlet and a throat portion disposed therebetween. The cooling jacket surrounds the venturi nozzle and a suction tube through which the fluid is being drawn into the venturi nozzle. Coolant flows through the cooling jacket. The cooling jacket dissipates heat generated by the venturi nozzle to prevent vapor lock.
Wagner, Jr., Edward P. (Idaho Falls, ID)
Turbine blade cooling
A turbine rotor blade comprises a shank portion, a tip portion and an airfoil. The airfoil has a pressure side wall and a suction side wall that are interconnected by a plurality of partition sidewalls, defining an internal cooling passageway within the airfoil. The internal cooling passageway includes at least one radial outflow passageway to direct a cooling medium flow from the shank portion towards the tip portion and at least one radial inflow passageway to direct a cooling medium flow from the tip portion towards the shank portion. A number of mixing ribs are disposed on the partition sidewalls within the radial outflow passageways so as to enhance the thermal mixing of the cooling medium flow, thereby producing improved heat transfer over a broad range of the Buoyancy number.
Staub, Fred Wolf (Schenectady, NY); Willett, Fred Thomas (Niskayuna, NY)
Got Web? Investing in a District Website
School and school district websites began to mushroom in the mid-1990s in what looked like a rush to stake a cyber-claim in a new frontier. As a byproduct, these early experiments also seemed like a good place to let parents know what is going on in the local school district. Today, it is all too easy to find district websites that are little more�
Swann, Patricia A.
Analytical investigation of chord size and cooling methods on turbine blade cooling requirements. Book 1: Sections 1 through 8 and appendixes A through I
A study was conducted to determine the effect of chord size on air cooled turbine blades. In the preliminary design phase, eight turbine blade cooling configurations in 0.75-in., 1.0-in., and 1.5-in. chord sizes were analyzed to determine the maximum turbine inlet temperature capabilities. A pin fin convection cooled configuration and a film-impingement cooled configuration were selected for a final design analysis in which the maximum turbine inlet temperature was determined as a function of the cooling air inlet temperature and the turbine inlet total pressure for each of the three chord sizes. The cooling air flow requirements were also determined for a varying cooling air inlet temperature with a constant turbine inlet temperature. It was determined that allowable turbine inlet temperature increases with increasing chord for the convection cooled and transpiration cooled designs, however, the film-convection cooled designs did not have a significant change in turbine inlet temperature with chord.
Faulkner, F. E.
77 FR 21556 - Don Pedro Hydroelectric Project: Turlock Irrigation District; Modesto Irrigation District...
...Federal Energy Regulatory Commission [Project No. 2299-075] Don Pedro Hydroelectric Project: Turlock Irrigation District; Modesto Irrigation District; Supplement to Notice of Study Dispute Resolution Technical Conference On March 16,...
District's Workforce: Annual Report Required by the District of Columbia Retirement Reform Act.
An enrolled actuary was engaged by the District of Columbia Retirement Board to (1) determine the 1990 disability retirement rate for District police officers and firefighters hired before February 15, 1980; (2) determine if that rate exceeded eight-tenth...
Sisyphus cooling of electrically trapped polyatomic molecules.
Polar molecules have a rich internal structure and long-range dipole-dipole interactions, making them useful for quantum-controlled applications and fundamental investigations. Their potential fully unfolds at ultracold temperatures, where various effects are predicted in many-body physics, quantum information science, ultracold chemistry and physics beyond the standard model. Whereas a wide range of methods to produce cold molecular ensembles have been developed, the cooling of polyatomic molecules (that is, with three or more atoms) to ultracold temperatures has seemed intractable. Here we report the experimental realization of optoelectrical cooling, a recently proposed cooling and accumulation method for polar molecules. Its key attribute is the removal of a large fraction of a molecule's kinetic energy in each cycle of the cooling sequence via a Sisyphus effect, allowing cooling with only a few repetitions of the dissipative decay process. We demonstrate the potential of optoelectrical cooling by reducing the temperature of about one million CH(3)F molecules by a factor of 13.5, with the phase-space density increased by a factor of 29 (or a factor of 70 discounting trap losses). In contrast to other cooling mechanisms, our scheme proceeds in a trap, cools in all three dimensions and should work for a large variety of polar molecules. With no fundamental temperature limit anticipated down to the photon-recoil temperature in the nanokelvin range, we expect our method to be able to produce ultracold polyatomic molecules. The low temperatures, large molecule numbers and long trapping times of up to 27 seconds should allow an interaction-dominated regime to be attained, enabling collision studies and investigation of evaporative cooling towards a Bose-Einstein condensate of polyatomic molecules. PMID:23151480
Zeppenfeld, Martin; Englert, Barbara G U; Gl�ckner, Rosa; Prehn, Alexander; Mielenz, Manuel; Sommer, Christian; van Buuren, Laurens D; Motsch, Michael; Rempe, Gerhard
Molecule formation in cool, dense interstellar clouds
A discussion is given of the general processes and considerations that arise in attempting to understand molecular reactions in cool, dense interstellar clouds. Basic elements of the gas phase, 'ion-molecule' scheme are given explicitly before surveying topics in which there is considerable current activity. These topics include: (1) refined comparisons of prediction and observation for species of 'intermediate' complexity, (2)
W. D. Watson
Electron Cooling Rates Characterization at Fermilab's Recycler.
A 0.1 A, 4.3 MeV DC electron beam is routinely used to cool 8 GeV antiprotons in Fermilab's Recycler storage ring. The primary function of the electron cooler is to increase the longitudinal phase-space density of the antiprotons for storing and preparing...
A. Shemyakin L. R. Prost
Multilayer composite material and method for evaporative cooling
A multilayer composite material and method for evaporative cooling of a person employs an evaporative cooling liquid that changes phase from a liquid to a gaseous state to absorb thermal energy. The evaporative cooling liquid is absorbed into a superabsorbent material enclosed within the multilayer composite material. The multilayer composite material has a high percentage of the evaporative cooling liquid in the matrix. The cooling effect can be sustained for an extended period of time because of the high percentage of phase change liquid that can be absorbed into the superabsorbent. Such a composite can be used for cooling febrile patients by evaporative cooling as the evaporative cooling liquid in the matrix changes from a liquid to a gaseous state to absorb thermal energy. The composite can be made with a perforated barrier material around the outside to regulate the evaporation rate of the phase change liquid. Alternatively, the composite can be made with an imperveous barrier material or semipermeable membrane on one side to prevent the liquid from contacting the person's skin. The evaporative cooling liquid in the matrix can be recharged by soaking the material in the liquid. The multilayer composite material can be fashioned into blankets, garments and other articles.
Buckley, Theresa M. (Inventor)
Cooling of solar flares plasmas. 1: Theoretical considerations
Theoretical models of the cooling of flare plasma are reexamined. By assuming that the cooling occurs in two separate phase where conduction and radiation, respectively, dominate, a simple analytic formula for the cooling time of a flare plasma is derived. Unlike earlier order-of-magnitude scalings, this result accounts for the effect of the evolution of the loop plasma parameters on the cooling time. When the conductive cooling leads to an 'evaporation' of chromospheric material, the cooling time scales L(exp 5/6)/p(exp 1/6), where the coronal phase (defined as the time maximum temperature). When the conductive cooling is static, the cooling time scales as L(exp 3/4)n(exp 1/4). In deriving these results, use was made of an important scaling law (T proportional to n(exp 2)) during the radiative cooling phase that was forst noted in one-dimensional hydrodynamic numerical simulations (Serio et al. 1991; Jakimiec et al. 1992). Our own simulations show that this result is restricted to approximately the radiative loss function of Rosner, Tucker, & Vaiana (1978). for different radiative loss functions, other scaling result, with T and n scaling almost linearly when the radiative loss falls off as T(exp -2). It is shown that these scaling laws are part of a class of analytic solutions developed by Antiocos (1980).
Cargill, Peter J.; Mariska, John T.; Antiochos, Spiro K.
Reforming Districts: How Districts Support School Reform. A Research Report. Document R-03-6
School districts have participated in multiple rounds of education reform activity in the past few decades, yet few have made headway on system-wide school improvement. This paper addresses the questions of whether districts matter for school reform progress and what successful "reforming" districts do to achieve system change and to navigate the�
McLaughlin, Milbrey; Talbert, Joan
Inter-District Cooperation: Salvation of the Small School District. New Regionalism.
In its least complex form, a cooperative can be an informal agreement between two or more school districts to cooperatively accomplish some task. As a cooperative gets more formalized and organized, with its own staff, its operations become more removed the control of its constituents and member districts. The local school district's primary�
Hartman, Luther E.
A Report and Estimating Tool for K-12 School Districts. Missouri District Case Study
The Missouri district is a small rural school district with 450 students and 51 staff with a total of 210 client computers. The district consists of two schools (K-6 and 7-12) housed in a single building. This document contains the results of the four 2004 Total Cost of Ownership (TCO) case studies: (1) Software costs; (2) Hardware costs; (3)�
Consortium for School Networking, 2004
One Approach to Increasing Revenues for Your School District. (A Small School District's Successful Struggle).
In 1983, Channahon School District 17 in Illinois was $1.3 million in debt. Real estate taxes constituted the school district's chief source of revenue, but because the state's oil industry kept its assessed valuations below the actual value of its property through the use of experts and lawyers, the school district was denied much of its income.�
Dombrowski, Richard J.
Influence of the cooling circulation water on the efficiency of a thermonuclear plant
In the present study, the feasibility of intercalating two cooling towers in the present circulation water system used at Almaraz Nuclear Power Plant, located at Campo Ara�uelo district (SW Spain), has been technically evaluated in order to increase the efficiency of the thermodynamic cycle used at present. Thus, the working cycle has been analyzed, the power produced by the turbines
J. Ga��n; A. Rahman Al-Kassir; J. F. Gonz�lez; A. Mac??as; M. A. Diaz
Topical Report : NSTF Facilities Plan for Water-Cooled VHTR RCCS : Normal Operational Tests.
As part of the Department of Energy (DOE) Generation IV roadmapping activity, the gas-cooled Very High Temperature Reactor (VHTR) has been selected as the principal concept for hydrogen production and other process-heat applications such as district heati...
C. P. Tzanos D. J. Kilsdonk M. T. Farmer R. W. Aeschlimann S. Lomperski
Coagulation chemistries for silica removal from cooling tower water
The formation of silica scale is a problem for thermoelectric power generating facilities, and this study investigated the potential for removal of silica by means of chemical coagulation from source water before it is subjected to mineral concentration in cooling towers. In Phase I, a screening of many typical as well as novel coagulants was carried out using concentrated cooling
May Devan Nyman; Susan Jeanne Altman; Tom Stewart
Progress in Designing a Muon Cooling Ring with Lithium Lenses.
We discuss particle tracking simulations in a storage ring with lithium lens inserts designed for the six-dimensional phase space cooling of muons by the ionization cooling. The ring design contains one or more lithium lens absorbers for transverse coolin...
Y. Fukui D. B. Cline A. A. Garren H. G. Kirk
Experience with supercritical helium cooling on a rocket sensor
A large telescoped infrared sensor was successfully flown on a rocket. A supercritical helium cryogenic system was used to cool the various parts of the sensor and to avoid cooling problems associated with liquid\\/gas phase mixing during the weightless part of the flight. The design and operational experience are presented. Since the flight of the sensor lasted only eight minutes,
Donald P. Saletnik; Jens Peter Dybwad
Optical correlator notch filters for Fermilab debuncher betatron stochastic cooling
Optical correlator notch filters have been installed in the Fermilab Antiproton Debuncher ring. Their main function is the improvement of system signal-to-noise ratio without degradation of system gain and phase parameters. This is turn yields faster cooling times that are compatible with the more rapid antiproton production cycles proposed for future operation. A brief discussion of cooling techniques is presented,
Ralph J. Pasquinelli; William Kells; David Peterson; John Marriner
Implementation of Stochastic Cooling Hardware at Fermilab's Tevatron Collider
The invention of Stochastic cooling by Simon van der Meer made possible the increase in phase space density of charged particle beams. In particular, this feedback technique allowed the development of proton antiproton colliders at both CERN and Fermilab. This paper describes the development of hardware systems necessary to cool antiprotons at the Fermilab Tevatron Collider complex.
Pasquinelli, Ralph J.; /Fermilab
A possible ionization cooling experiment at the AGS
Ionization cooling may play an important role in reducing the phase space volume of muons for a future muon-muon collider. We describe possible transverse and longitudinal emittance cooling experiments that utilize the capabilities of the AGS at Brookhaven National Laboratory. {copyright} {ital 1995 American Institute of Physics.}
Fernow, R.C.; Gallardo, J.C.; Palmer, R.B. [Brookhaven National Laboratory, Upton, New York 11973 (United States); Winn, D.R. [Fairfield University, Fairfield, Connecticut 06430 (United States); Neuffer, D.V. [CEBAF, Newport News, Virginia 23606 (United States)
Ionization cooling may play an important role in reducing the phase space density of muons for a future muon-muon collider. The authors describe possible transverse and longitudinal emittance cooling experiments that utilize the capabilities of the AGS at Brookhaven National Laboratory.
Fernow, R.C.; Gallardo, J.C.; Palmer, R.B. [Brookhaven National Lab., Upton, NY (United States); Winn, D.R. [Fairfield Univ., CT (United States); Neuffer, D.V. [CEBAF, Newport News, VA (United States)
Ionization cooling may play an important role in reducing the phase space volume of muons for a future muon-muon collider. We describe possible transverse and longitudinal emittance cooling experiments that utilize the capabilities of the AGS at Brookhaven National Laboratory.
Richard C. Fernow; Juan C. Gallardo; Robert B. Palmer; David Winn; David Neuffer
Survey Of Cooling Techniques
Methods of maintaining electronics at best operating temperatures reviewed. Paper surveys cooling techniques for electronic components and sensors that must be kept at temperatures ranging from thousandths of kelvin to room temperature. Discusses characteristics of various coolers in terms of ground and space applications, cooling capacity, reliability, and temperature range. Also discusses briefly, cooling of conventional electronic circuitry operating few degrees above environmental temperature by natural or forced convection of air or liquid. At greater length, discusses passive and active refrigeration of "cold" electronic circuitry operating below environmental temperature.
Chan, Chung K.
An important concern facing electronics designers is heat dissipation. Especially in laptop computers and server farms, overheating can be a major problem. ElectronicsCooling is a free, quarterly publication that provides "practical information to the reader that relates to cooling of today's electronics." Every article since the magazine's debut in 1995 can be viewed from this site. Common topics are packaging, thermal design, and technical data related to many types of electronics. Contributions to ElectronicsCooling are generally from industry and academia.
For heavy-particle beams in storage rings where there is no significant synchrotron radiation damping, beam cooling is an essential tool in obtaining high phase-space density high brightness beams. Advances in various types of cooling such as electron, stochastic, laser and muon cooling are covered in dedicated Conferences. In this series of Workshops (HB2002-06), discussions are aimed only at a few specific subjects which are crucial for future projects. The discussion topics in our session closely followed those discussed during the HB2004 workshop [1]. Specifically, we concentrated on the topics of electron cooling and intrabeam scattering, motivated by the design of the future high-energy coolers [2,3,4]. These cooling projects at high-energy require accurate numerical modeling and experimental verification. A variety of tasks were put together at HB2004 [1]. In our working group we discussed a progress in addressing these tasks. We had 10 presentations [5]-[14] (with additional presentations in the joint sessions) which followed by dedicated discussions. Our main topics of discussions: intrabeam scattering (IBS), electron cooling, and beam stability are summarized.
Metallographic Cooling Rate of IVA Irons Revisited
There is long standing problem reconciling the chemical evidence that the IVA iron meteorites formed in a core with the diverse cooling rates reported by several researchers. This large inferred range of cooling rates suggests that the IVA irons were distributed at different depths in a parent body with a complex structure when the Widmanstatten pattern formed. On the other hand, some researchers argued that the diverse cooling rates in group IVA result from inaccurate model parameters such as phase diagram, interdiffusion coefficients, and kamacite nucleation and growth mechanisms. In addition, the measured cooling rates may not apply for the same cooling temperature ranges, and the variation in the crystallographic orientations of the Widmanstatten plates on the analysis surface may result in inaccurate measurements of widths needed for the computer simulation models. We have revaluated the major parameters in computer model developed by Hopfe and Goldstein and measured cooling rates for the IVA irons. Such data are useful in evaluating whether these meteorites were part of a single core of a parent body during the formation of the Widmanstatten pattern.
Yang, J.; Goldstein, J. I.; Scott, E. R. D.
20 CFR 704.301 - Administration; compensation districts.
Code of Federal Regulations, 2013 CFR
...Administration; compensation districts. 704.301 Section 704...ACT AND RELATED STATUTES SPECIAL PROVISIONS FOR LHWCA EXTENSIONS...Administration; compensation districts. For the purpose of administration...this Act, the compensation districts established under...
20 CFR 704.401 - Administration; compensation districts.
...Administration; compensation districts. 704.401 Section 704...ACT AND RELATED STATUTES SPECIAL PROVISIONS FOR LHWCA EXTENSIONS...Administration; compensation districts. For the purpose of administration...Alaska, the compensation districts established for...
20 CFR 704.201 - Administration; compensation districts.
...Administration; compensation districts. 704.201 Section 704...ACT AND RELATED STATUTES SPECIAL PROVISIONS FOR LHWCA EXTENSIONS District of Columbia Workmen's Compensation...Administration; compensation districts. For the purpose of...
Cool luminous stars
The consequences of magnetic fields for the atmospheres of cool stars are addressed based on IUE and Einstein Observatory observations. Gross atmospheric structure data for cool luminous stars are discussed, and the relevance of the observations for the energy balance and nonradiative heating rates is considered. Data from X-ray fluxes, low dispersion UV spectra, and high dispersion spectra in the region of the Mg II resonance lines are presented. New results on cool star atmospheres provided by high dispersion UV spectra are considered, including those pertaining to spectral line identification, identification of emission components in close binary systems, densities and atmospheric extension, emission line widths, properties of stellar winds as derived from IUE data, and systematic flows of transition region plasma. An explanation for the observed spectra of cool giants and supergiants is proposed in terms of active, quiet, and hybrid stars.
Linsky, J. L.
Cooled Echelle Grating Spectrometer.
A cooled echelle grating spectrometer for detecting wavelengths between one micrometers and fifteen micrometers is described. More specifically, a spectrometer is disclosed, having a cross-dispersing grating for ordering infrared energy, and an echelle gr...
R. Beer
Bunched beam stochastic cooling
The scaling laws for bunched-beam stochastic cooling has been derived in terms of the optimum cooling rate and the mixing condition. In the case that particles occupy the entire sinusoidal rf bucket, the optimum cooling rate of the bunched beam is shown to be similar to that predicted from the coasting-beam theory using a beam of the same average density and mixing factor. However, in the case that particles occupy only the center of the bucket, the optimum rate decrease in proportion to the ratio of the bunch area to the bucket area. The cooling efficiency can be significantly improved if the synchrotron side-band spectrum is effectively broadened, e.g. by the transverse tune spread or by using a double rf system.
Wei, Jie
Wei, Jie.
Waveguide cooling system
An improved system is described for cooling high power waveguides by the use of cooling ducts extending along the waveguide, which minimizes hot spots at the flanges where waveguide sections are connected together. The cooling duct extends along substantially the full length of the waveguide section, and each flange at the end of the section has a through hole with an inner end connected to the duct and an opposite end that can be aligned with a flange hole in another waveguide section. Earth flange is formed with a drainage groove in its face, between the through hole and the waveguide conduit to prevent leakage of cooling fluid into the waveguide. The ducts have narrowed sections immediately adjacent to the flanges to provide room for the installation of fasteners closely around the waveguide channel.
Chen, B. C. J.; Hartop, R. W. (inventors)
Solar refrigeration and cooling
In this paper a review of solar cooling and refrigeration technologies is presented. A discussion on the main reasons why these technologies are not presently economically feasible is carried out. and two installations in Mexico are analysed.
R. Best; N. Ortega
Evaporative Cooling Membrane Device
An evaporative cooling membrane device is disclosed having a flat or pleated plate housing with an enclosed bottom and an exposed top that is covered with at least one sheet of hydrophobic porous material having a thin thickness so as to serve as a membrane. The hydrophobic porous material has pores with predetermined dimensions so as to resist any fluid in its liquid state from passing therethrough but to allow passage of the fluid in its vapor state, thereby, causing the evaporation of the fluid and the cooling of the remaining fluid. The fluid has a predetermined flow rate. The evaporative cooling membrane device has a channel which is sized in cooperation with the predetermined flow rate of the fluid so as to produce laminar flow therein. The evaporative cooling membrane device provides for the convenient control of the evaporation rates of the circulating fluid by adjusting the flow rates of the laminar flowing fluid.
Lomax, Curtis (Inventor); Moskito, John (Inventor)
Elementary Stochastic Cooling.
Major headings in this review include: proton sources; antiproton production; antiproton sources and Liouville, the role of the Debuncher; transverse stochastic cooling, time domain; the accumulator; frequency domain; pickups and kickers; Fokker-Planck eq...
A. V. Tollestrup G . Dugan
Cool Teens, Uncool Future?
Supporting Solo at the District Level
School librarians in the Mesquite Independent School District (ISD) have been operating solo on their campuses since the 1970s. Campus clerical assistance in the school libraries was a luxury that they couldn't afford. Since the district's vision was of a teaching librarian, a Library Processing Department was established in 1972. As years passed,�
Woodard, Mary
The Soil Conservation District Movement in Tennessee.
The development of soil conservation districts in Tennessee is the subject of this graduate study. Related literature, existing records, and personal interviews are used to record progress since Tennessee adopted Public Law 46 establishing soil conservation districts in 1939. In 1959 all 95 counties of Tennessee had organized soil conservation�
Mathews, Thomas Cochran; And Others
5 Steps to a Greener School District
Sometimes all it takes is a little fate to accomplish something great, or in this case, something green. The Broward County Public School (BCPS) District shows how a natural disaster (Hurricane Wilma) inspired a green revolution. This article presents the five steps that the Broward County School District followed in implementing an Environmental�
Hines, Gary
Perspectives on facilities management for industrial districts
The possible evolution of facility management (FM) in industrial districts, which characterise Italian industrial system, is analysed. The paper investigates structural features of industrial districts, mainly formed by small sized enterprises, and how they influence the attributes of the FM market. An aggregation matrix is introduced to identify technical opportunities such as replicated, centralised and distributed facilities and management for
Antonella Meneghetti; Damiana Chinese
Amid Uncertainty, Districts Weighing "Sequester" Impact
Even as they seek to quantify the impact of across-the-board federal budget cuts on K-12 programs, some of the nation's neediest school districts are bracing for tough choices. The pinch from sequestration--or "the sequester," in Washington shorthand--is expected to be particularly painful for districts that depend on the most on the federal�
Klein, Alyson
Districts as Institutional Actors in Educational Reform
Purpose: Intermittent attention to the district as the unit of study has left a void in our understanding of the complexities associated with the ability of district-level leaders to contribute to successful, systemic educational reform. In this article, the authors address this void by providing a narrative synthesis of previous findings,�
Rorrer, Andrea K.; Skrla, Linda; Scheurich, James Joseph
Shared Bus Garage Serves District, City.
Through a joint venture between the school district and the municipality of Scarsdale (New York), the district's buses are serviced in a $2 million maintenance and ground facility. The arrangement has reduced vehicle down time, saved wear and tear on the buses, and reduced fuel consumption. (MLF)
Delude, Rita
District Awards for Teacher Excellence: Research Brief
Since 2008 Texas's District Awards for Teacher Excellence (D.A.T.E.) program has provided grants to districts for the implementation of locally designed incentive pay plans. The 2010-11 school year is the third year of the D.A.T.E. incentive pay plans with approximately $197 million in annual state funding. This research brief summarizes the key�
National Center on Performance Incentives, 2010
District heating for the state of Minnesota
The Minnesota Energy Agency is actively involved in implementing new hot water cogeneration district heating systems in Moorhead (POP 34,000), Red Wing (POP 13000), and St. Paul (POP 310,000). These projects have been funded by the Department of Energy, the State and the cities. The district heating systems designed will use coal and cogenerated thermal energy from existing electric generation
Districts Create Community Connections with Social Media
More districts realize that communicating in a clear and engaging way with stakeholders about everything from the district's overall education vision to scholastic and extracurricular success stories can go a long way toward enlisting broad community support. And although face-to-face communications are still important, technology provides a�
Gordon, Dan
Teacher-Quality Checklist for School Districts
Many districts struggle with multiple--and often incompatible--data systems for tracking payroll, collecting teacher evaluations, recruiting and hiring. Aligning these systems and annually assessing where a district stands is the first step towards developing a smart human capital strategy. This checklist outlines the goals, data and questions a�
National Council on Teacher Quality, 2010
Districts More Strategic about Hiring Teachers
A handful of urban districts, such as Denver, the District of Columbia, Pittsburgh, and Tulsa, Oklahoma, are taking steps to practice "strategic hiring." The efforts consist of collecting a more-robust set of information on candidates, developing stronger relationships with teacher-preparation programs, and tracking new hires to determine their�
Sawchuk, Stephen
A Case Study of School District Consolidation
Several New England states have been rethinking the system whereby small towns make the key decisions about school budgets and staffing under the banner of local control. Maine already has mandated a reduction in the number of local school districts from 290 to 80, allowing localities to vote on the larger districts. This consolidation, unpopular�
Cronin, Joseph M.
School Turnarounds: The Essential Role of Districts
The inspiration for this book was a crucial observation: that if the school turnaround movement is to have widespread and lasting consequences, it will need to incorporate meaningful district involvement in its efforts. The result is a volume that considers school turnaround efforts at the district level, examining the evidence thus far and�
Zavadsky, Heather
Episodic Instability in School District Elections.
Presents data from four California districts supporting the Iannaconne/Lutz theory that democratic control of school district policy occurs through episodic voter dissatisfaction leading to incumbent defeat and changes in school administration. Further asserts that the typical length of a change episode extends for as many as four successive�
Criswell, Larry W.; Mitchell, Douglas E.
School Attendance and District and School Size
The size of schools and districts in which they are located has become a salient policy issue in recent years. While consolidation of school districts and expanding high school size were in vogue from the 1960s until recently, funding agencies are now sponsoring projects to reduce school size under the assumption that smaller schools will lead to�
Jones, John T.; Toma, Eugenia F.; Zimmer, Ron W.
Industrial Districts: Old Wine in New Bottles?
HARRISON B. (1992) Industrial districts: old wine in new bottles?, Reg. Studies26, 469�483. According to the theory of industrial districts, a new wave of economic growth is being led in a number of regions in Europe, North America and East Asia by spatially concentrated networks of mostly small and medium sized enterprises, often using flexible production technology and characterized by
Bennett Harrison
Stress amongst district nurses: a preliminary investigation
Summary � This paper presents the results of a pilot study investigating stress among district nurses in the north-west of England. Nurses completed questionnaires covering job satisfaction, mental health, stress, Type A behaviour, health behaviour, coping skills and demographic details. � A specific measure of stress was developed following in-depth interviews with primary care professionals, including district nurses. A total
USHA USHA; RANI ROUT; M Sc
Charleston County School District (CCSD) Reading Policy.
This brief two-page policy statement presents the Charleston County (South Carolina) School District Board of Trustees reading policy. It begins by noting that the district will emphasize early literacy development, reading across the content areas, and interventions for struggling readers, and that schools shall be responsible for designing and�
Charleston County School District, North Charleston, SC.
Grantmaking to School Districts: Lessons for Foundations
This brief offers lessons and best practices from foundations across the country on grantmaking to school districts. It offers advice to foundations that are considering school district investments for the first time. It also offers a useful "check" to more experienced foundations that want to examine their thinking and approaches against the�
Coffman, Julia; Weiss, Heather; Harris, Erin; Little, Priscilla M. D.
Districts Abandon Grants Targeting Teacher Quality
Three big-city districts--Chicago, Milwaukee, and New York--have terminated federal grants aimed at promoting performance-based compensation plans and professional development for teachers and principals. Overall, the 2010 Teacher Incentive Fund (TIF) grants to the three districts would have provided an $88 million payout over five years--nearly 7�
Zubrzycki, Jaclyn
Characteristics of Improved School Districts. Research Brief
This research brief presents an overview of a 2004 study by G.S. Shannon and P. Bylsma entitled "Characteristics of Improved School Districts: Themes from Research" (Olympia, WA: Office of Superintendent of Public Instruction). The authors reviewed more than 80 research articles that investigated the attributes of schools and districts that have�
Center for Comprehensive School Reform and Improvement, 2006
Lessons in Innovative Funding for District Improvements
Near the shores of Lake Superior, Michigan's Houghton-Portage Township School District is known for academic leadership and strives to provide an exceptional and secure learning environment for its students. However, like many districts around the country, Houghton-Portage is not immune to the economic restrictions. In a recent effort to address�
McDaniel, Gwenn
Comprehensive District Reform: Philadelphia's Grand Experiment.
This report describes "Philadelphia's Grand Experiment" in comprehensive school district reform, from its conception through its initial months of implementation. In 2001, as part of the remedy for low student performance, the governor ordered the state to take over governance of the Philadelphia School District, with a substantial number of�
Useem, Elizabeth; Balfanz, Robert
Refrigerant directly cooled capacitors
The invention is a direct contact refrigerant cooling system using a refrigerant floating loop having a refrigerant and refrigeration devices. The cooling system has at least one hermetic container disposed in the refrigerant floating loop. The hermetic container has at least one electronic component selected from the group consisting of capacitors, power electronic switches and gating signal module. The refrigerant is in direct contact with the electronic component.
Hsu, John S. (Oak Ridge, TN); Seiber, Larry E. (Oak Ridge, TN); Marlino, Laura D. (Oak Ridge, TN); Ayers, Curtis W. (Kingston, TN)
Neutron star cooling
The impact of nuclear physics theories on cooling of isolated neutron stars\\u000ais analyzed. Physical properties of neutron star matter important for cooling\\u000aare reviewed such as composition, the equation of state, superfluidity of\\u000avarious baryon species, neutrino emission mechanisms. Theoretical results are\\u000acompared with observations of thermal radiation from neutron stars. Current\\u000aconstraints on theoretical models of dense matter,
D. G. Yakovlev; O. Y. Gnedin; M. E. Gusakov; A. D. Kaminker; K. P. Levenfish; A. Y. Potekhin
Neutron Star Cooling
Observation of cooling neutron stars can potentially provide information\\u000aabout the states of matter at supernuclear densities. We review physical\\u000aproperties important for cooling such as neutrino emission processes and\\u000asuperfluidity in the stellar interior, surface envelopes of light elements due\\u000ato accretion of matter and strong surface magnetic fields. The neutrino\\u000aprocesses include the modified Urca process, and the
D. G. Yakovlev; O. Y. Gnedin
Cooled flameholder swirl cup
US Patent & Trademark Office Database
A combustor swirl cup includes coaxial inner and outer swirlers separated by a tubular centerbody. The centerbody includes a bypass inlet surrounding the inner swirler and diverges aft along a perforate inner nozzle to terminate at an annular flameholder. An impingement ring is spaced forward from the flameholder in flow communication with the bypass inlet for receiving cooling air therefrom to impingement cool the flameholder.
Geothermal district heating system feasibility analysis, Thermopolis, Wyoming
The purpose of this study is to determine the technical and economic feasibility of constructing and operating a district heating system to serve the residential, commercial, and public sectors in Thermopolis. The project geothermal resource assessment, based on reviews of existing information and data, indicated that substantial hot water resources likely exist in the Rose Dome region 10 miles northeast of Thermopolis, and with quantities capable of supporting the proposed geothermal uses. Preliminary engineering designs were developed to serve the space heating and hot water heating demands for buildings in the Thermopolis-East Thermopolis town service area. The heating district design is based on indirect geothermal heat supply and includes production wells, transmission lines, heat exchanger units, and the closed loop distribution and collection system necessary to serve the individual customers. Three options are presented for disposal of the cooled waters-reinjection, river disposal, and agricultural reuse. The preliminary engineering effort indicates the proposed system is technically feasible. The design is sized to serve 1545 residences, 190 businesses, and 24 public buildings. The peak design meets a demand of 128.2 million Btu at production rates of 6400 gpm.
Goering, S.W.; Garing, K.L.; Coury, G.; Mickley, M.C.
A 500 kW X-Band Air-Cooled Ferrite Latching Switch
The design of a high-power air-cooled microwave SPDT switch which is capable of operation at peak and average power levels of 500 kW and 666 watts, respectively, is described. The unit is of a differential phase shift circulator design employing 90� nonreciprocal phase shift elements which are forced air cooled. The phase shifter design employs dual ferrite toroids, \\
R. A. Stern; J. P. Agrios
Passive cooling has shown to be a very dependable cryogenic cooling method for space missions. Several missions employ passive radiators to cool down their delicate sensor systems for many years, without consuming power, without exporting vibrations or producing electromagnetic interference. So for a number of applications, passive cooling is a good choice. At lower temperatures, the passive coolers run into
D. J. Doornink; J. F. Burger; H. J. M. ter Brake
Jan Doornink; Johannes Burger; Marcel ter Brake
University District Oral History Project
The Seattle Public Library has been embarking on some ambitious projects as of late and this oral history initiative is one of the best. Working with students in the University of Washington Museology Graduate Program, a number of oral history interviews were conducted with residents, businesspeople, and others in the city's University District. All of the interviews were conducted in 2011 and each interviewee provided a unique viewpoint of life on "The Ave,� which is shorthand for the main street that runs north and south through the neighborhood. There are twelve interviews here, including one with a University of Washington student, a Seattle Police Department officer, and the director of a teen outreach group.
Metering cooling flows in the water-cooled gas turbine
Metering of coolant flow to bucket cooling passages in the water-cooled gas turbine rotor was experimentally evaluated. Through water flow per cooling passage is approximately one gallon per hour and rotor ''g'' field is approximately 20,000 g's, the water-cooled gas turbine depends on uniform water distribution. Measurements indicative of water distribution accuracy to eight buckets and representative cooling passages in
Hybrid Evaporative - Condenser Cooling Tower
The need to save energy in power producing and power consuming systems and the fact that evaporative cooling is the most efficient method for heat rejection led to the design and testing of a model of a special cooling tower, fn this hybrid system an evaporative condenser is being built into the cooling tower and the advantages of evaporative cooling
Uriyel Fisher; Wolfgang Leidenfrost; Jiashang Li
Impingement/effusion cooling
Impingement/effusion cooling offers one of the most effective ways of cooling gas turbine combustor walls and turbine blades. The design principles are reviewed and cooling effectiveness data presented for a range of typical geometries with holes at 90 degrees to the surface. The main variable studied was the number of impingement/effusion holes. Comparison was made with the effusion cooling effectiveness. Optimum configurations were demonstrated with a 0.7 overall cooling effectiveness at a mass flow per unit surface area of 0.2 kg/sm(exp 2)bar. This was equivalent to 10 percent of the combustor air flow for a typical gas turbine combustor. Data is also presented for the overall wall heat transfer coefficient. The mechanism of the enhanced heat transfer within the impingement/effusion double skin wall was investigated using a CFD code. This predicted the complex aerodynamics in the impingement gap and also gave good agreement with the measured overall heat transfer data.
Andrews, G. E.; Aldabagh, A. M.; Asere, A. A.; Bazdidi-Tehrani, F.; Mkpadi, M. C.; Nazari, A.
Cooling-water treatment
This article examines how new chemicals, application technology, and control systems enhance treatment of water for cooling and powerplant reuse, while minimizing discharges to protect the environment. Effective operation of cooling-water treatment systems continues to hinge on the control of scaling, fouling, and corrosion. Though these maladies have not changed in nature over recent years, the operating problems encountered have intensified considerably. Depletion and degradation of water sources and environmental concerns have been the driving forces for change. In some states, regulations--such as California`s Title 22--now mandate the use of reclaimed water (treated sewage) and are harbingers of future trends. While these and other influences combine to reduce freshwater consumption and wastewater discharge, they force reliance on poorer-quality, more aggressive water in powerplant cooling systems. Responses to the challenge include a continuing move from once-through to recirculating systems featuring cooling towers, higher-cycle operation of existing cooling-tower systems, and improvements in treatment chemicals, technology, and controls.
Puckorius, P.R.; Strauss, S.D.
The neutrino factory program aims to produce well-characterized neutrino fluxes, orders of magnitude larger than those available from conventional beams. An important feature of the machine design is a cooling section for reducing the muon transverse emittance to a level that can be accepted by the downstream accelerators and be contained in the storage ring. We describe simulations of a high-performance ionization cooling channel for the front end of a neutrino factory. The design considered here consists of a solenoidal lattice with alternating polarity and 2.75 m and 1.65 m cell lengths. Simulations show that the cooling increases the phase space density into the acceptance of the following linac by a factor of 3.
Cooling in a compound bucket
Electron cooling in the Fermilab Recycler ring is found to create correlation between longitudinal and transverse tails of the antiproton distribution. By separating the core of the beam from the tail and cooling the tail using 'gated' stochastic cooling while applying electron cooling on the entire beam, one may be able to significantly increase the overall cooling rate. In this paper, we describe the procedure and first experimental results.
Shemyakin, A.; Bhat, C.; Broemmelsiek, D.; Burov, A.; Hu, M.; /Fermilab
Research on solar energy storage subsystems utilizing the latent heat of phase change of paraffin hydrocarbons for the heating and cooling of buildings. Semi-annual report, September 1, 1974March 31, 1975
An analytical and experimental research program designed to assess the potential of a solar energy storage subsystem (thermal capacitor) utilizing the latent heat of fusion of paraffin hydrocarbons for the heating and cooling of buildings, and supported with grant funds from the National Science Foundation, is described. An idealized model of a flat plate thermal capacitor based on uniaxial heat
Design and development of LH2 cooled rolling element radial bearings for the NERVA engine turbopump. Volume 3: Phase 2: Tests on build-ups 16, 17, and 18 at NRDS, Jackass Flats, Nevada, December 1971 - March 1972
The use of liquid hydrogen to cool the rolling element radial bearings in the nuclear engine for rocket vehicles is discussed. The fifteen hour service life goal was obtained during the tests. The increase in bearing life was also considered to be produced by: (1) improvements in bearing material, (2) bearing retainer configuration and manufacturing changes, and (3) better control of operating parameters.
Accinelli, J. B.; Koch, D. A.; Reuter, F.
We introduce plans for electron-cooling of the Relativistic Heavy Ion Collider (RHIC). This project has a number of new features as electron coolers go: It will cool 100 GeV/nucleon ions with 50 MeV electrons; it will be the first attempt to cool a collider at storage-energy; and it will be the first cooler to use a bunched beam and a linear accelerator as the electron source. The linac will be superconducting with energy recovery. The electron source will be based on a photocathode gun. The project is carried out by the Collider-Accelerator Department at BNL in collaboration with the Budker Institute of Nuclear Physics.
Winds from cool stars
Spectral observations of cool stars enable study of the presence and character of winds and the mass loss process in objects with effective temperatures, gravities, and atmospheric compositions which differ from that of the Sun. A wealth of recent spectroscopic measurements from the Hubble Space Telescope, and the Extreme Ultraviolet Explorer complement high resolution ground-based measures in the optical and infrared spectral regions. Such observations when combined with realistic semi-empirical atmospheric modeling allow us to estimate the physical conditions in the atmospheres and winds of many classes of cool stars. Line profiles support turbulent heating and mass motions. In low gravity stars, evidence is found for relatively fast (approximately 200 km s(exp -1)), warm winds with rapid acceleration occurring in the chromosphere. In some cases outflows commensurate with stellar escape velocities are present. Our current understanding of cool star winds will be reviewed including the implications of stellar observations for identification of atmospheric heating and acceleration processes.
Dupree, A. K.
S'COOL Tutorial
This tutorial provides detailed information about the importance of ground truth measurements for investigative science and various cloud properties. CERES measurements contribute to our understanding of the interaction between clouds and solar energy, the most significant factor controlling our climate. Students� Cloud Observations On-Line (S'COOL) is a K-12 educational outreach effort of Clouds and the Earth's Radiant Energy System (CERES), a NASA instrument that observes Earth from space. S'COOL involves students in making ground truth observations of clouds for comparison with satellite data. S'COOL involves four basic steps, which are explained in the tutorial: determining satellite overpass time, observing cloud properties, transmitting results to NASA, and comparing results with satellite-retrieved properties.
We report progress on the R&D program for electron-cooling of the Relativistic Heavy Ion Collider (RHIC). This electron cooler is designed to cool 100 GeV/nucleon at storage energy using 54 MeV electrons. The electron source will be a superconducting RF photocathode gun. The accelerator will be a superconducting energy recovery linac. The frequency of the accelerator is set at 703.75 MHz. The maximum electron bunch frequency is 9.38 MHz, with bunch charge of 20 nC. The R&D program has the following components: The photoinjector and its photocathode, the superconducting linac cavity, start-to-end beam dynamics with magnetized electrons, electron cooling calculations including benchmarking experiments and development of a large superconducting solenoid. The photoinjector and linac cavity are being incorporated into an energy recovery linac aimed at demonstrating ampere class current at about 20 MeV.
Emittance growth due to Intra-Beam Scattering significantly reduces the heavy ion luminosity lifetime in RHIC. Stochastic cooling of the stored beam could improve things considerably by counteracting IBS and preventing particles from escaping the rf bucket [1]. High frequency bunched-beam stochastic cooling is especially challenging but observations of Schottky signals in the 4-8 GHz band indicate that conditions are favorable in RHIC [2]. We report here on measurements of the longitudinal beam transfer function carried out with a pickup kicker pair on loan from FNAL TEVATRON. Results imply that for ions a coasting beam description is applicable and we outline some general features of a viable momentum cooling system for RHIC.
Respiratory cooling in rattlesnakes.
We used infrared thermography to study respiratory cooling in the rattlesnakes (Viperidae: Crotalinae) and to partition the effects of air temperature, humidity, and activity levels on head-body temperature differences. We observed a single, cooled region centered around the mouth and nasal capsule that extended across the pit membrane at air temperatures above 20 degrees C. Both head and body temperatures of rattlesnakes increased linearly with air temperature. Head-body temperature differentials also increased with air temperature, but declined significantly at higher relative humidities. Rattling rattlesnakes exhibited significantly greater head-body temperature differentials than did resting rattlesnakes. We suggest that respiratory cooling may provide a thermal buffer for the thermoreceptive pit organs at high air temperatures, but caution that this adaptive hypothesis must be tested with direct neural or behavioral assays. PMID:15936707
Borrell, Brendan J; Laduc, Travis J; Dudley, Robert
A passive containment cooling system includes a containment vessel surrounding a reactor pressure vessel and defining a drywell therein containing a non-condensable gas. An enclosed wetwell pool is disposed inside the containment vessel, and a gravity driven cooling system (GDCS) pool is disposed above the wetwell pool in the containment vessel and is vented to the drywell. An isolation pool is disposed above the GDCS pool and includes an isolation condenser therein. The condenser has an inlet line disposed in flow communication with the drywell for receiving the non-condensable gas along with any steam released therein following a loss-of-coolant accident (LOCA). The condenser also has an outlet line disposed in flow communication with the drywell for returning to the drywell both liquid condensate produced upon cooling of the steam and the non-condensable gas for reducing pressure within the containment vessel following the LOCA. 1 figure.
Billig, P.F.; Cooke, F.E.; Fitch, J.R.
A passive containment cooling system includes a containment vessel surrounding a reactor pressure vessel and defining a drywell therein containing a non-condensable gas. An enclosed wetwell pool is disposed inside the containment vessel, and a gravity driven cooling system (GDCS) pool is disposed above the wetwell pool in the containment vessel and is vented to the drywell. An isolation pool is disposed above the GDCS pool and includes an isolation condenser therein. The condenser has an inlet line disposed in flow communication with the drywell for receiving the non-condensable gas along with any steam released therein following a loss-of-coolant accident (LOCA). The condenser also has an outlet line disposed in flow communication with the drywell for returning to the drywell both liquid condensate produced upon cooling of the steam and the non-condensable gas for reducing pressure within the containment vessel following the LOCA.
Billig, Paul F. (San Jose, CA); Cooke, Franklin E. (San Jose, CA); Fitch, James R. (San Jose, CA)
Mojave Field Trips or Mining Districts
This web site hosts field trips to 10 localities in the Mojave area of southeastern California and southwestern Nevada. Most of the localities are mining districts or mines. They include: Calico Mining District, Waterman Mine, Mohawk Mine and Copper World Mine, Mountain Pass Mine, Colosseum Mine, the Goodsprings District with Red Cloud Mine and Keystone Mine, Snow White Mine, Beck Iron Mine, War Eagle Mine, and several stops in the Mammoth/Owens Valley area. The commodities include gold, silver, copper, zinc, iron, lead, barite, and talc. Sketches give the geology and mining history of the areas and may include cross sections and simple geologic maps.
Jessey, David
Mechano-caloric cooling device
The mechano-caloric effect is potentially useful in the He II temperature range. Aside from demonstration work, little quantification effort appears to have been known since other refrigeration possibilities have been available for some time. Successful He II use-related system examples are as follows: in space, the utilization of the latent heat of vaporization has been quite successful in vapor-liquid phase separation (VLPS) in conjunction with thermomechanical force application in plugs. In magnet cooling systems, the possibility of using the mechano-caloric cooling effect in conjunction with thermo-mechanical circulation pump schemes, has been assessed (but not quantified yet to the extent desirable). A third example is quoted in conjunction with superfluid wind tunnel studies and liquid helium tow tank for surface vessels respectively. In all of these (partially future) R and D areas, the question of refrigerator effectiveness using the mechano-caloric effect appears to be relevant, possibly in conjunction with questions of reliability and simplicity. The present work is concerned with quantification of phenomena including simplified thermodynamic cycle calculations.
Frederking, T. H. K.; Luna, Jack; Abbassi, P.; Carandang, R. M.
Coronal Structures in Cool Stars
Many papers have been published that further elucidate the structure of coronas in cool stars as determined from EUVE, HST, FUSE, Chandra, and XMM-Newton observations. In addition we are exploring the effects of coronas on the He I 1083081 transition that is observed in the infrared. Highlights of these are summarized below including publications during this reporting period and presentations. Ground-based magnetic Doppler imaging of cool stars suggests that active stars have active regions located at high latitudes on their surface. We have performed similar imaging in X-ray to locate the sites of enhanced activity using Chandra spectra. Chandra HETG observations of the bright eclipsing contact binary 44i Boo and Chandra LETG observations for the eclipsing binary VW Cep show X-ray line profiles that are Doppler-shifted by orbital motion. After careful analysis of the spectrum of each binary, a composite line-profile is constructed by adding the individual spectral lines. This high signal-to-noise ratio composite line-profile yields orbital velocities for these binaries that are accurate to 30 km/sec and allows their orbital motion to be studied at higher time resolutions. In conjunction with X-ray lightcurves, the phase-binned composite line-profiles constrain coronal structures to be small and located at high latitudes. These observations and techniques show the power of the Doppler Imaging Technique applied to X-ray line emission.
Oliversen, Ronald (Technical Monitor); Dupree, Andrea K.
Cooling rate effect on vacuum brazed joint properties for 2205 duplex stainless steels
The influence of cooling rates and fillers on the mechanical properties and corrosion resistance of vacuum brazed joints for two types of 2205 duplex stainless steels was investigated. The amount of a sigma phase precipitated in the duplex stainless steel (DSS) was increased at a slow cooling rate. When the cooling rate was increased to 0.25�C s?1, the suppression of
L. H. Chiu; W. C. Hsieh; C. H. Wu
The thermal evolution of IVA iron meteorites: evidence from metallographic cooling rates
Metallographic cooling rates of group IVA iron meteorites have been recalculated based on the most recent Ni diffusion coefficients and phase diagram. The cooling rates are revised upwards by a factor of ca. 15 relative to previous estimates. A large range in cooling rate is found in the low-Ni part of group IVA (Ni
Kaare L. Rasmussen; Finn Ulff-M�ller; Henning Haack
Thermal cooling data for figs exposed to air cooling
This paper implies the presentation of a methodology for determining the thermal cooling data in terms of the cooling coefficients, lag factors, half cooling times and seven-eighths cooling times, as well as the heat transfer coefficients of the food products. This methodology was employed to determine the thermal cooling data for the individual figs being cooled with air at the flow velocities of 1.1, 1.5, 1.75, and 2.5 m/s. The results of this study show that the cooling coefficient and lag factor varied linearly, the half cooling time and seven-eighths cooling time decreased by 21.5% and 20.9% and the heat transfer coefficient increased by 27.3% with increasing air-flow velocity from 1.1 to 2.5 m/s.
Dincer, I. [TUBITAK-Marmara Research Center, Gebze (Turkey)] [TUBITAK-Marmara Research Center, Gebze (Turkey)
Non-equilibrium cooling rate for a collisionally cooled metal-enriched gas
We present self-consistent calculations of non-equilibrium (time-dependent) cooling rates for a dust-free collisionally controlled gas in wide ranges of temperature (10 ? T ? 108 K) and metallicity (10-4 ? Z ? 2 Z?). We confirm that molecular hydrogen dominates cooling at 102 ? T ? 104 K and Z ? 10- 3 Z?. We find that the contribution from H2 into the cooling rate around T � (4-5) � 103 K stimulates thermal instability in the metallicity range Z ? 10- 2 Z?. Isobaric cooling rates are generally lower than isochoric cooling rates, because the associated increase of gas density leads to both more efficient hydrogen recombination and equilibration of the fine-structure level populations. Isochoric cooling means that the ionization fraction remains quite high at T ? 104 K - up to �0.01 at T ? 103 K and Z ? 0.1 Z?, and even higher at higher metallicity - unlike isobaric cooling, where it is at least an order of magnitude lower. Despite this increase in ionization fraction, the gas-phase formation rate of molecular hydrogen (via H-) decreases with metallicity, because higher metallicity shortens the evolution time. We implement our self-consistent cooling rates into the multidimensional parallel code ZEUS-MP in order to simulate the evolution of a supernova remnant. We compare it to an analogous model with tabulated cooling rates published in previous studies. We find significant differences between the two descriptions, which might appear, for example, in the mixing of the ejected metals in the circumstellar medium.
Vasiliev, Evgenii O.
Cooling with Sunshades
This is a lesson about passive cooling methods. Learners will construct a simple device to measure how effective different materials are for protecting against sunlight, explain how heat relates to the motion of atoms and molecules, describe how heat can be transmitted from one place to another, explain how sunlight arriving on Earth interacts with matter, and describe how MESSENGER is protected by a simple sunshade in the hot Mercurian environment. Materials required to do this activity include several commonly-found items (e.g., coffee cans, ice cubes, tape, ruler, calculators, stopwatch, and scale). This is lesson 3 of 4 at the Grade 9-12 range of "Staying Cool."
Combustor liner cooling system
A combustor liner is disclosed. The combustor liner includes an upstream portion, a downstream end portion extending from the upstream portion along a generally longitudinal axis, and a cover layer associated with an inner surface of the downstream end portion. The downstream end portion includes the inner surface and an outer surface, the inner surface defining a plurality of microchannels. The downstream end portion further defines a plurality of passages extending between the inner surface and the outer surface. The plurality of microchannels are fluidly connected to the plurality of passages, and are configured to flow a cooling medium therethrough, cooling the combustor liner.
Lacy, Benjamin Paul; Berkman, Mert Enis
How giant planets cool
Understanding how giant planets cool is key to the study of their interior structure, composition and hence formation. I will review how the observed luminosities of Jupiter, Saturn, Uranus and Neptune may be accounted for, mostly by convective transport of heat limited by the atmospheric lip, but with several complications (sedimentation of helium droplets, gradients of composition...). Conversely, I will show that the the cooling of strongly irradiated giant planets ("Pegasids") is limited by heat transport in a thick external radiative zone with a possibility of a significant dissipation of heat due to tides. In all cases, both radiative transport and atmospheric/interior dynamics play crucial roles and require further studies.
Guillot, T.
Bee Cool! (Honeybee Thermoregulation)
In this open-ended investigation students determine how honeybees heat their larvae (brood) when it�s cold and how they cool the brood when it�s hot. In the process, students will discover the physical principals that make thermoregulation possible. Required materials and step-by-step instructional guidelines are included in a pdf guide. Teachers and students may extend upon this activity by using their �honeybee� investigations to design open-ended experiments to determine ways to heat and cool things through direct contact (conduction), through the movement of air or water (convection), and by evaporation.
Bob Madsen, Dull K.
Superconductor rotor cooling system
A system for cooling a superconductor device includes a cryocooler located in a stationary reference frame and a closed circulation system external to the cryocooler. The closed circulation system interfaces the stationary reference frame with a rotating reference frame in which the superconductor device is located. A method of cooling a superconductor device includes locating a cryocooler in a stationary reference frame, and transferring heat from a superconductor device located in a rotating reference frame to the cryocooler through a closed circulation system external to the cryocooler. The closed circulation system interfaces the stationary reference frame with the rotating reference frame.
Gamble, Bruce B. (Wellesley, MA); Sidi-Yekhlef, Ahmed (Framingham, MA); Schwall, Robert E. (Northborough, MA); Driscoll, David I. (South Euclid, OH); Shoykhet, Boris A. (Beachwood, OH)
Innovation in forage development: empirical evidence from Alaba Special District, southern Ethiopia
Forage development is one of the strategies to address feed scarcity and low livestock productivity in Ethiopia. In line with government strategy, multiple actors took part in a forage development programme for six years (2004�09) in Alaba Special District, in southern Ethiopia. This paper analyses the six-year forage development programme, comparing its two phases, from an innovation systems perspective to
Abebe Shiferaw; Ranjitha Puskur; Azage Tegegne; Dirk Hoekstra
Case Study of a Collaborative University/School District Teacher Induction Program: Issues and Recommendations.
Describes a collaborative effort between a Nevada school district and the University of Nevada to support first-year teachers. The internship program provided mentoring, support, and services to first-year teachers. The article describes the three-phase approach to collaboration and offers recommendations for collaborative programs. (SM)
Krajewski, Junean J.; Cheney, Christine O.
Developing and Establishing Local School District Goals. Volume 2 in the PERM Handbook Series.
To help Connecticut school districts both develop goals and involve the community in the process--phase 1 of the planning, evaluation, and resource management (PERM) model--this handbook discusses goal-setting processes and models. An introduction notes the state's educational goals, outlines the PERM model, and describes the role of goals in�
Connecticut State Dept. of Education, Hartford. Bureau of Research, Planning, and Evaluation.
Muon Beam Helical Cooling Channel Design
The Helical Cooling Channel (HCC) achieves effective ionization cooling of the six-dimensional (6d) phase space of a muon beam by means of a series of 21st century inventions. In the HCC, hydrogen-pressurized RF cavities enable high RF gradients in strong external magnetic fields. The theory of the HCC, which requires a magnetic field with solenoid, helical dipole, and helical quadrupole components, demonstrates that dispersion in the gaseous hydrogen energy absorber provides effective emittance exchange to enable longitudinal ionization cooling. The 10-year development of a practical implementation of a muon-beam cooling device has involved a series of technical innovations and experiments that imply that an HCC of less than 300 m length can cool the 6d emittance of a muon beam by six orders of magnitude. We describe the design and construction plans for a prototype HCC module based on oxygen-doped hydrogen-pressurized RF cavities that are loaded with dielectric, fed by magnetrons, and operate in a superconducting helical solenoid magnet.
Johnson, Rolland; Ankenbrandt, Charles; Flanagan, G.; Kazakevich, G.M.; Marhauser, Frank; Neubauer, Michael; Roberts, T.; Yoshikawa, C.; Derbenev, Yaroslav; Morozov, Vasiliy; Kashikhin, V.S.; Lopes, Mattlock; Tollestrup, A.; Yonehara, Katsuya; Zloblin, A.
An Analysis of a High Performing School District's Culture
This report describes a problem based learning project focusing on the cultural elements of a high performing school district. Current literature on school district culture provides numerous cultural elements that are present in high performing school districts. With the current climate in education placing pressure on school districts to perform�
Corum, Kenneth D.; Schuetz, Todd B.
School District Employment Reductions Slow. Get the Facts. #1
Kansas school districts reduced employment by 327 full-time equivalent positions this school year, the smallest reduction in three years of cuts to district operating budgets. Districts reduced positions by 561 in FY 2010 and 1,626 in FY 2011. Districts eliminated nearly 400 "regular" teaching positions this year, but added 114 special education�
Tallman, Mark
District variations in educational resources and student outcomes
Since the 1970s, poorer school districts lacking educational resources have formed coalitions and sued their respective states. Their lawsuits claim that interdistrict variations in educational resources violate state constitutions because they deny poorer school districts an equal educational opportunity. Using data from school districts in Virginia, this research investigates two questions. First, whether a school district's level of educational resources
James D. Unnever; Allan C. Kerckhoff; Timothy J. Robinson
Recipe for Financial Disaster: Three Districts Tell Their Story.
Examines three school districts [Richmond Unified School District (California), Coachella Valley Unified School District (California), and White Pine County School District (Nevada)] that faced financial disaster and then worked their way back to solvency. All three overspent revenues in the general fund, had unrealistic budgets, and lacked�
Manca, Donna; Noonan, David; Matranga, Myrna
PCM Passive Cooling System Containing Active Subsystems
A multistage system has been proposed for cooling a circulating fluid that is subject to intermittent intense heating. The system would be both flexible and redundant in that it could operate in a basic passive mode, either sequentially or simultaneously with operation of a first, active cooling subsystem, and either sequentially or simultaneously with a second cooling subsystem that could be active, passive, or a combination of both. This flexibility and redundancy, in combination with the passive nature of at least one of the modes of operation, would make the system more reliable, relative to a conventional cooling system. The system would include a tube-in-shell heat exchanger, within which the space between the tubes would be filled with a phase-change material (PCM). The circulating hot fluid would flow along the tubes in the heat exchanger. In the basic passive mode of operation, heat would be conducted from the hot fluid into the PCM, wherein the heat would be stored temporarily by virtue of the phase change.
Blanding, David E.; Bass, David I.
Turbomachine rotor with improved cooling
A gas turbine rotor has an essentially closed loop cooling air scheme in which cooling air drawn from the compressor discharge air that is supplied to the combustion chamber is further compressed, cooled, and then directed to the aft end of the turbine rotor. Downstream seal rings attached to the downstream face of each rotor disc direct the cooling air over the downstream disc face, thereby cooling it, and then to cooling air passages formed in the rotating blades. Upstream seal rings attached to the upstream face of each disc direct the heated cooling air away from the blade root while keeping the disc thermally isolated from the heated cooling air. From each upstream seal ring, the heated cooling air flows through passages in the upstream discs and is then combined and returned to the combustion chamber from which it was drawn.
Hultgren, Kent Goran (Winter Park, FL); McLaurin, Leroy Dixon (Winter Springs, FL); Bertsch, Oran Leroy (Titusville, FL); Lowe, Perry Eugene (Oviedo, FL)
Curved film cooling admission tube
Effective film cooling to protect a wall surface from a hot fluid which impinges on or flows along the surface is provided. A film of cooling fluid having increased area is provided by changing the direction of a stream of cooling fluid through an angle of from 135 deg. to 165 deg. before injecting it through the wall into the hot flowing gas. The 1, cooling fluid is injected from an orifice through a wall into a hot flowing gas at an angle to form a cooling fluid film. Cooling fluid is supplied to the orifice from a cooling fluid source via a turbulence control passageway having a curved portion between two straight portions. The angle through which the direction of the cooling fluid is turned results in less mixing of the cooling fluid with the hot gas, thereby substantially increasing the length of the film in a downstream direction.
Graham, R. W.; Papell, S. S. (inventors)
A gas turbine rotor has an essentially closed loop cooling air scheme in which cooling air drawn from the compressor discharge air that is supplied to the combustion chamber is further compressed, cooled, and then directed to the aft end of the turbine rotor. Downstream seal rings attached to the downstream face of each rotor disc direct the cooling air over the downstream disc face, thereby cooling it, and then to cooling air passages formed in the rotating blades. Upstream seal rings attached to the upstream face of each disc direct the heated cooling air away from the blade root while keeping the disc thermally isolated from the heated cooling air. From each upstream seal ring, the heated cooling air flows through passages in the upstream discs and is then combined and returned to the combustion chamber from which it was drawn. 5 figs.
Hultgren, K.G.; McLaurin, L.D.; Bertsch, O.L.; Lowe, P.E.
Development of District Heating 1983-1995.
This report describes the development of district heating in Sweden. The following aspects are discussed more in detail: The method used to estimate the future increase. The economy compared to other systems. The potential and prognosis of extension. Use ...
P. Gorpe J. Enqvist M. Borchers
7 CFR 953.11 - District.
...2. Northampton County in the State of Virginia...City and Nansemond Counties and the cities of...Currituck, and Camden Counties in the State of North Carolina. District No. 5. Halifax, Nash, Edgecombe, Pitt,...
Energy Emergency Districts: Concepts and Applications.
This final report describes the development and evaluation of models of the Energy Emergency District concept, and also explores potential applications of the concept for enhancing emergency management procedures. Part I provides summary descriptions of t...
R. B. Stewart
Hitaveita (district heating) in Akureyri
Akureyri is a town of 15,000 inhabitants located in central N-Iceland. It has been heated by geothermal energy since the end of the seventies. Prior to that, it was partly heated by electricity, but mainly with oil burners, located within individual buildings. During the period 1928-1970, several attempts were made to exploit known hot spring areas in the vicinity of Akureyri. These attempts failed. Following the jump in energy price during the oil crisis of 1973, considerable effort was put into further exploration. Based on resistivity soundings, the Laugaland field was selected for deep drilling. In 1975, this resulted in the discovery of a big feed zone, which initially yielded around 100 1/s of 90{degrees}C hot water by free flow. Two years later another big feed zone was located at the Ytri-Tjarnir geothermal field initially yielding 50 1/2 of 80{degrees}C water. Based on short-term pump tests, and simulations by the Theis model, it was estimated that these two fields together could yield 240 1/s with a water level drawdown to 190 m below the surface. This was expected to satisfy the energy need for space heating in Akureyri. In 1977, Hitaveita Akureyrar was, therefore, established. Construction of the district heating system was initiated in 1976 and most of the town had been connected in 1979.
Flovenz, O.G.; Axelsson, G. [Orkustofnun, Reykjavik (Iceland); Arnason, F.; Finnsson, M. [Hitaveita Akureyrar, Akureyri (Iceland)
The ReDistricting Game
The Redistricting Game is designed to educate, engage, and empower citizens around the issue of political redistricting. Currently, the political system in most states allows the state legislators themselves to draw the lines. This system is subject to a wide range of abuses and manipulations that encourage incumbents to draw districts which protect their seats rather than risk an open contest.By exploring how the system works, as well as how open it is to abuse, The Redistricting Game allows players to experience the realities of one of the most important (yet least understood) aspects of our political system. The game provides a basic introduction to the redistricting system, allows players to explore the ways in which abuses can undermine the system, and provides info about reform initiatives - including a playable version of the Tanner Reform bill to demonstrate the ways that the system might be made more consistent with tenets of good governance. Beyond playing the game, the web site for The Redistricting Game provides a wealth of information about redistricting in every state as well as providing hands-on opportunities for civic engagement and political action.
California, University O.
Warm and Cool Cityscapes
Painting cityscapes is a great way to teach first-grade students about warm and cool colors. Before the painting begins, the author and her class have an in-depth discussion about big cities and what types of buildings or structures that might be seen in them. They talk about large apartment and condo buildings, skyscrapers, art museums,�
Jubelirer, Shelly
Winds from Cool Stars
The structure of the outer atmospheres of luminous cool stars reveals the evolution of magnetic activity as dynamo heating decreases and atmospheres expand while the stars evolve across the color-magnitude diagram. The relationship between winds and high temperature material can also be investigated. A comprehensive picture of the dynamics of the outer atmospheres is constructed based principally upon recent spectroscopic
A. K. Dupree
The structure of the outer atmospheres of luminous cool stars reveals the evolution of magnetic activity as dynamo heating decreases and atmospheres expand while the stars evolve across the color-magnitude diagram. The relationship between winds and high temperature material can also be investigated. A comprehensive picture of the dynamics of the outer atmospheres is constructed based principally upon recent spectroscopic evidence from FUSE HST and optical and infrared spectra. In contrast to the solar example winds from cool giant and supergiant stars can exhibit supersonic acceleration in their chromospheres carry away more material and possess temperatures ranging from 10000K to 80000K. Coronal material near 107 K appears confined and does not participate in atmospheric expansion. Empirical relations between atmospheric structure and mass loss will be discussed. For metal deficient stars the discovery of signatures of pulsation may play an important role in driving mass loss. The detection of warm winds in cool giants and supergiants provides the crucial link between the hot fast solar wind with low mass loss and cool slow supergiant winds with substantially larger rates of mass loss.
Cooling tower waste reduction
At Lawrence Livermore National Laboratory (LLNL), the two main cooling tower systems (central and northwest) were upgraded during the summer of 1997 to reduce the generation of hazardous waste. In 1996, these two tower systems generated approximately 135,400 lbs (61,400 kg) of hazardous sludge, which is more than 90 percent of the hazardous waste for the site annually. At both,
S. J. Coleman; J. Celeste; R. Chine; C. Scott
Designing Cool Components
A NASA SBIR contract served as the beginning for the development of Daat Research Corporation's Coolit software. Coolit is a unique computational fluid dynamics (CFD) application aimed at thermal and cooling design problems. Coolit can generate 3-D representations of the thermofluid environment and "sketch" the component on the computer. The software modeling reduces time and effort in prototype building and testing.
Composite Cooled Rotor Blade.
A description is given of a composite cooled blade, for example for a gas or steam turbine rotor, consisting of a detachable root with a coolant chamber and a blade section with profiled ducts. To increase static and vibration strength and operational rel...
N. Y. Litvinov V. S. Lyubinetskii
Transpiration Cooling Experiment
The transpiration cooling method was considered for a scram-jet engine to accommodate thermally the situation where a very high heat flux (200 Btu/sq. ft sec) from hydrogen fuel combustion process is imposed to the engine walls. In a scram-jet engine, a small portion of hydrogen fuel passes through the porous walls of the engine combustor to cool the engine walls and at the same time the rest passes along combustion chamber walls and is preheated. Such a regenerative system promises simultaneously cooling of engine combustor and preheating the cryogenic fuel. In the experiment, an optical heating method was used to provide a heat flux of 200 Btu/sq. ft sec to the cylindrical surface of a porous stainless steel specimen which carried helium gas. The cooling efficiencies by transpiration were studied for specimens with various porosity. The experiments of various test specimens under high heat flux have revealed a phenomenon that chokes the medium flow when passing through a porous structure. This research includes the analysis of the system and a scaling conversion study that interprets the results from helium into the case when hydrogen medium is used.
Song, Kyo D.; Ries, Heidi R.; Scotti, Stephen J.; Choi, Sang H.
Liquid-Cooled Brassiere.
A device is described for enhancing the detection of malignant tissue in the breasts of a woman. It is comprised of a brassiere-like garment which is fitted with a pair of liquid-perfused cooling panels which completely and compliantly cover the breasts a...
W. Elkins B. A. Williams E. G. Tickner
Electron Cooling of RHIC
We report progress on the R&D program for electron-cooling of the Relativistic Heavy Ion Collider (RHIC). This electron cooler is designed to cool 100 GeV/nucleon at storage energy using 54 MeV electrons. The electron source will be a superconducting RF photocathode gun. The accelerator will be a superconducting energy recovery linac. The frequency of the accelerator is set at 703.75 MHz. The maximum electron bunch frequency is 9.38 MHz, with bunch charge of 20 nC. The R&D program has the following components: The photoinjector and its photocathode, the superconducting linac cavity, start-to-end beam dynamics with magnetized electrons, electron cooling calculations including benchmarking experiments and development of a large superconducting solenoid. The photoinjector and linac cavity are being incorporated into an energy recovery linac aimed at demonstrating ampere class current at about 20 MeV. A Zeroth Order Design Report is in an advanced draft state, and can be found on the web at http://www.agsrhichome.bnl.gov/eCool/.
I. Ben-Zvi; D.S. Barton; D.B. Beavis; M. Blaskiewicz; J.M. Brennan; A. Burrill; R. Calaga; P. Cameron; X.Y. Chang; R. Connolly; Yu.I. Eidelman; A.V. Fedotov; W. Fischer; D.M. Gassner; H. Hahn; M. Harrison; A. Hershcovitch; H.-C. Hseuh; A.K. Jain; P.D.J. Johnson; D. Kayran; J. Kewisch; R.F. Lambiase; V. Litvinenko; W.W. MacKay; G.J. Mahler; N. Malitsky; G.T. McIntyre; W. Meng; K.A.M. Mirabella; C. Montag; T.C.N. Nehring; T. Nicoletti; B. Oerter; G. Parzen; D. Pate; J. Rank; T. Rao; T. Roser; T. Russo; J. Scaduto; K. Smith; D. Trbojevic; G. Wang; J. Wei; N.W.W. Williams; K.-C. Wu; V. Yakimenko; A. Zaltsman; Y. Zhao; D.T. Abell; D.L. Bruhwiler; H. Bluem; A. Burger; M.D. Cole; A.J. Favale; D. Holmes; J. Rathke; T. Schultheiss; A.M.M. Todd; A.V. Burov; S. Nagaitsev; J.R. Delayen; Y.S. Derbenev; L. W. Funk; P. Kneisel; L. Merminga; H.L. Phillips; J.P. Preble; I. Koop; V.V. Parkhomchuk; Y.M. Shatunov; A.N. Skrinsky; I. Koop; V.V. Parkhomchuk; Y.M. Shatunov; A.N. Skrinsky; J.S. Sekutowicz
This is an open-ended investigation to determine how honeybees heat their larvae (brood) when it��s cold and how they cool the brood when it��s hot. Students will also discover the physical principals that make thermoregulation possible.
Mr. Bob Madsen (Dull Knife Memorial College)
Evaporative roof cooling system
An evaporative roof cooling system is described for placement upon a roof surface exposed to relatively high levels of solar radiation causing high under roof temperatures and comprising: (a) water distribution mist\\/spray nozzles positioned on the roof surface for supplying substantially uniform mist\\/sprays of water to lay down a substantially uniform thin film of water on the roof surface; (b)
Cooled Vane Cluster.
A cast vane cluster with enhanced cooling contains an inner and an outer platform and at least two airfoils for directing a primary fluid stream axially rearward. A duct is bounded by inner, an outer endwall surfaces, and adjacent airfoil fluid directing ...
E. Pietraszkiewicz T. Coons
Actively cooled silicon mirrors
The performance advantages of using silicon for actively cooled mirrors are developed through a comparison with molybdenum mirrors, the type used most extensively for high-energy CW laser applications. In particular, maximum temperatures and distortions are related to a power loading parameter. Factors which are likely to limit the operating capabilities of both types of mirrors are considered to assess their
F. M. Anthony; A. K. Hopkins
Elementary stochastic cooling
Major headings in this review include: proton sources; antiproton production; antiproton sources and Liouville, the role of the Debuncher; transverse stochastic cooling, time domain; the accumulator; frequency domain; pickups and kickers; Fokker-Planck equation; calculation of constants in the Fokker-Planck equation; and beam feedback. (GHT)
Tollestrup, A.V.; Dugan, G
Kuehlschmierstoffe. (Cooling lubricants).
As a rule, the base substances used are certain liquid hydrocarbons from mineral oils as well as from native and synthetic oils. Through the addition of further substances the cooling lubricant takes on the particular qualities required for the use in que...
W. Pfeiffer D. Breuer H. Blome C. Deininger J. U. Hahn
A review of recently reported cooling tower plume models yields none that is universally accepted. The entrainment and drag mechanisms and the effect of moisture on the plume trajectory are phenomena which are treated differently by various investigators. In order to better under...
Chromospheres of Cool Stars.
Progress in understanding the nature and origin of cool star chromospheres and transition regions since the launch of IUE is reviewed. While previous observations in the visible and UV regions laid the foundations for present work, the nature of the IUE i...
C. Jordan