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Office of Scientific and Technical Information
Fluid Flow Modeling in Fractures
E-Print Network [OSTI]
In this paper we study fluid flow in fractures using numerical simulation and address the challenging issue of hydraulic property characterization in fractures. The methodology is based on Computational Fluid Dynamics, ...
Sarkar, Sudipta
MODELING COUPLED FLUID FLOW AND GEOMECHANICAL AND GEOPHYSICAL PHENOMENA WITHIN A FINITE ELEMENT between pore fluid flow and the concurring deformation of the solid rock matrix. The governing equations and constitutive relations of fluid flow are coupled to stress-strain relations. With the appropriate boundary
Monitoring and Modeling Fluid Flow in a Developing EGS Reservoir...
Broader source: Energy.gov (indexed) [DOE]
More Documents & Publications Imaging, Characterizing, and Modeling of Fracture Networks and Fluid Flow in EGS Reservoirs Detection and Characterization of Natural...
1 MATHEMATICAL MODELING AND SIMULATION FOR FLUID FLOW IN POROUS MEDIA Ewing, Richard Texas A is to understand the complex chemical, physical, and fluid flow processes occurring in an underground porous medium with one pass through these four steps. Once a computer code has been developed which gives concrete
Ewing, Richard E.
Can We Accurately Model Fluid Flow in Shale?
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
2013 00:00 Over 20 trillion cubic meters of natural gas are trapped in shale, but many shale oil and gas producers still use models of underground fluid flow that date back to...
Modeling Fluid Flow in Natural Systems, Model Validation and...
rock, flow is primarily in relatively sparse networks of fractures. Discrete fracture network (DFNs) models are an approach to representing flow in fractured rock that...
FLUID FLOW MODELING OF RESIN TRANSFER MOLDING FOR COMPOSITE MATERIAL WIND TURBINE BLADE STRUCTURES.............................................................................................................7 Composite Materials...................................................................................................7 Material Properties
Imaging, Characterizing, and Modeling of Fracture Networks and Fluid Flow in EGS Reservoirs
Broader source: Energy.gov [DOE]
Project objectives: Improve image resolution for microseismicimaging and time-lapse active seismic imaging; Enhance the prediction of fluid flow and temperature distributions and stress changes by coupling fracture flow simulations with reservoir flow simulations; and integrating imaging into modeling.
Monitoring and Modeling Fluid Flow in a Developing EGS Reservoir
Project objectives: Better understand and model fluid injection into a tight reservoir on the edges of a hydrothermal field. Use seismic data to constrain geomechanical/hydrologic/thermal model of reservoir.
Radiation Modeling In Fluid Flow Iain D. Boyd
· Closing remarks #12;3 Radiation In Fluid Flows · Radiation transport is an important phenomenon in many 5800 K #12;7 Fundamentals of Radiation Transport · Radiation does not require a medium !!! dI (s, ! ) ds +(p +g )I (s, ! )+ p I (s, ! ) Radiative Transfer Equation (RTE) - spectral intensity
Wang, Wei
Multiscale Modeling and Simulation of Fluid Flows in Inelastic Media
in porous media (e.g. soil), Elasticity equations in heterogeneous media (concrete, asphalt), etc porous media s The Fluid-Structure interaction (FSI) problem at the microscale and numerical methods with computational solutions s Numerical upscaling of flow in deformable porous media #12;- p. 3/42 Why homogenize
Popov, Peter
Numerical modeling of heat transfer and fluid flow in rotor-stator cavities with throughflow
Numerical modeling of heat transfer and fluid flow in rotor-stator cavities with throughflow S the dynamical effects from the heat transfer process. The fluid flow in an enclosed disk system with axial with heat transfer along the stator, which corresponds to the experiment of Djaoui et al. [2]. Our results
Boyer, Edmond
Computational Fluid Dynamics Modeling of a Lithium/Thionyl Chloride Battery with Electrolyte Flow
Computational Fluid Dynamics Modeling of a Lithium/Thionyl Chloride Battery with Electrolyte Flow W.B. Gu and C.Y. Wang GATE Center of Excellence for Advanced Energy Storage Department of Mechanical are performed using a finite volume method of computational fluid dynamics. The predicted discharge curves
Wang, Chao-Yang
A Preliminary Study to Assess Model Uncertainties in Fluid Flows
of the fluid. ? The sound speed, c, is assumed to be constant even if it usually depends on the temperature and the pressure. This is a good approximation for liquids but not for gases. The sound speed is reactor-dependent. ? The Equation Of State (EOS... to the temperature. This parameter is assumed constant in this model. 7 ? ???P is the dilatation of the density due to the pressure. This parameter is also assumed constant but is different for different sound speeds. Its expression is as follows: ?? ?P = 1...
Delchini, Marc Olivier
Mathematical Modeling and Simulation for Applications of Fluid Flow in Porous Media \\Lambda
Mathematical Modeling and Simulation for Applications of Fluid Flow in Porous Media \\Lambda Richard descriptions at various length scales, modeling the effects of this heterogeneity of the porous medium a computer code has been developed which gives concrete quantitative results for the total model, this out
Notes 10. A thermohydrodynamic bulk-flow model for fluid film bearings
The complete set of bulk-flow equations for the analysis of turbulent flow fluid film bearings. Importance of thermal effects in process fluid applications. A CFD method for solution of the bulk-flow equations....
San Andres, Luis
Fully coupled thermal-mechanical-fluid flow model for nonliner geologic systems
SciTech Connect (OSTI)
A single model is presented which describes fully coupled thermal-mechanical-fluid flow behavior of highly nonlinear, dynamic or quasistatic, porous geologic systems. The mathematical formulation for the model utilizes the continuum theory of mixtures to describe the multiphase nature of the system, and incremental linear constitutive theory to describe the path dependency of nonlinear material behavior. The model, incorporated in an explicit finite difference numerical procedure, was implemented in two different computer codes. A special-purpose one-dimensional code, SNEAKY, was written for initial validation of the coupling mechanisms and testing of the coupled model logic. A general purpose commercially available code, STEALTH, developed for modeling dynamic nonlinear thermomechanical processes, was modified to include fluid flow behavior and the coupling constitutive model. The fully explicit approach in the coupled calculation facilitated the inclusion of the coupling mechanisms and complex constitutive behavior. Analytical solutions pertaining to consolidation theory for soils, thermoelasticity for solids, and hydrothermal convection theory provided verification of stress and fluid flow, stress and conductive heat transfer, and heat transfer and fluid flow couplings, respectively, in the coupled model. A limited validation of the adequacy of the coupling constitutive assumptions was also performed by comparison with the physical response from two laboratory tests. Finally, the full potential of the coupled model is illustrated for geotechnical applications in energy-resource related areas. Examples in the areas of nuclear waste isolation and cut-and-fill mining are cited.
Hart, R.D.
Start-up flow of a viscoelastic fluid in a pipe with fractional Maxwell's model
Unidirectional start-up flow of a viscoelastic fluid in a pipe with fractional Maxwell's model is studied. The flow starting from rest is driven by a constant pressure gradient in an infinite long straight pipe. By employing the method of variable separations and Heaviside operational calculus, we obtain the exact solution, from which the flow characteristics are investigated. It is found that the start-up motion of fractional Maxwell's fluid with parameters $\\alpha$ and $\\beta$, tends to be at rest as time goes to infinity, except the case of $\\beta=1$. This observation, which also can be predicted from the mechanics analogue of fractional Maxwell's model, agrees with the classical work of Friedrich and it indicates fractional Maxwell's fluid presents solid-like behavior if $\\be\
Di Yang; Ke-Qin Zhu
Numerical modeling of heat transfer and fluid flow in rotor-stator cavities with throughflow S in a rotor-stator cavity subjected to a superimposed throughflow with heat transfer. Nu- merical predictions field from the heat transfer process. The turbulent flux is approximated by a gradient hypothesis
CIRQ: Qualitative fluid flow modelling for aerospace FMEA applications Neal Snooke
M2 CIRQ: Qualitative fluid flow modelling for aerospace FMEA applications Neal Snooke Department- oped on top of the MCIRQ simulator with the aim to produce an automated FMEA for aircraft fuel systems similar to pre- viously developed automated electrical FMEA. Introduction This paper describes a circuit
Snooke, Neal
Fluid Flow Model Development for Representative Geologic Media | Department
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:YearRound-UpHeat PumpRecordFederal7.pdfFlash_2010_-24.pdfOverview Flow Cells for Energyof
- Also includes relevant well information * Developed sub-grid scale model of fracture permeability as a function of normal and shear displacements - Installed in the fully...
Flow modeling of flat oval ductwork elbows using computational fluid dynamics
Incompressible turbulent flow fields in heating, ventilating, and air-conditioning (HVAC) elbows were computed using an incompressible, three-dimensional computational fluid dynamics (CFD) solver implementing a {kappa}-{epsilon} turbulence model. Two different geometries were investigated, including 90-degree five-gore hard-bend and easy-bend flat oval elbows. The geometries represent a subset of many configurations analyzed in ASHRAE RP-854, Determination of Duct Fitting Resistance by Numerical Analysis. For each configuration, the zero-length pressure loss coefficient was calculated. The flow was described through contours of velocity and plots of static pressure. The Reynolds number for these flows was held constant at 100,000 based on duct diameter and mean fluid velocity.
Mahank, T.A.; Mumma, S.A. [Pennsylvania State Univ., University Park, PA (United States)
Magnetically stimulated fluid flow patterns
ScienceCinema (OSTI)
Sandia National Laboratories' Jim Martin and Kyle Solis explain research on the effects of magnetic fields on fluid flows and how they stimulate vigorous flows. Fluid flow is a necessary phenomenon in everything from reactors to cooling engines in cars.
Martin, Jim; Solis, Kyle
Optimization of a Two-Fluid Hydrodynamic Model of Churn-Turbulent Flow
A hydrodynamic model of two-phase, churn-turbulent flows is being developed using the computational multiphase fluid dynamics (CMFD) code, NPHASE-CMFD. The numerical solutions obtained by this model are compared with experimental data obtained at the TOPFLOW facility of the Institute of Safety Research at the Forschungszentrum Dresden-Rossendorf. The TOPFLOW data is a high quality experimental database of upward, co-current air-water flows in a vertical pipe suitable for validation of computational fluid dynamics (CFD) codes. A five-field CMFD model was developed for the continuous liquid phase and four bubble size groups using mechanistic closure models for the ensemble-averaged Navier-Stokes equations. Mechanistic models for the drag and non-drag interfacial forces are implemented to include the governing physics to describe the hydrodynamic forces controlling the gas distribution. The closure models provide the functional form of the interfacial forces, with user defined coefficients to adjust the force magnitude. An optimization strategy was devised for these coefficients using commercial design optimization software. This paper demonstrates an approach to optimizing CMFD model parameters using a design optimization approach. Computed radial void fraction profiles predicted by the NPHASE-CMFD code are compared to experimental data for four bubble size groups.
Donna Post Guillen
Nanoscale Pore Imaging and Pore Scale Fluid Flow Modeling in Chalk
For many rocks of high economic interest such as chalk, diatomite, tight gas sands or coal, nanometer scale resolution is needed to resolve the 3D-pore structure, which controls the flow and trapping of fluids in the rocks. Such resolutions cannot be achieved with existing tomographic technologies. A new 3D imaging method, based on serial sectioning and using the Focused Ion Beam (FIB) technology has been developed. FIB allows for the milling of layers as thin as 10 nanometers by using accelerated Ga+ ions to sputter atoms from the sample surface. After each milling step, as a new surface is exposed, a 2D image of this surface is generated. Next, the 2D images are stacked to reconstruct the 3D pore or grain structure. Resolutions as high as 10 nm are achievable using such a technique. A new robust method of pore-scale fluid flow modeling has been developed and applied to sandstone and chalk samples. The method uses direct morphological analysis of the pore space to characterize the petrophysical properties of diverse formations. Not only petrophysical properties (porosity, permeability, relative permeability and capillary pressures) can be computed but also flow processes, such as those encountered in various IOR approaches, can be simulated. Petrophysical properties computed with the new method using the new FIB data will be presented. Present study is a part of the development of an Electronic Core Laboratory at LBNL/UCB.
Tomutsa, Liviu; Silin, Dmitriy
Parameter estimation from flowing fluid temperature logging data in unsaturated fractured rock using multiphase inverse modeling
A simple conceptual model has been recently developed for analyzing pressure and temperature data from flowing fluid temperature logging (FFTL) in unsaturated fractured rock. Using this conceptual model, we developed an analytical solution for FFTL pressure response, and a semianalytical solution for FFTL temperature response. We also proposed a method for estimating fracture permeability from FFTL temperature data. The conceptual model was based on some simplifying assumptions, particularly that a single-phase airflow model was used. In this paper, we develop a more comprehensive numerical model of multiphase flow and heat transfer associated with FFTL. Using this numerical model, we perform a number of forward simulations to determine the parameters that have the strongest influence on the pressure and temperature response from FFTL. We then use the iTOUGH2 optimization code to estimate these most sensitive parameters through inverse modeling and to quantify the uncertainties associated with these estimated parameters. We conclude that FFTL can be utilized to determine permeability, porosity, and thermal conductivity of the fracture rock. Two other parameters, which are not properties of the fractured rock, have strong influence on FFTL response. These are pressure and temperature in the borehole that were at equilibrium with the fractured rock formation at the beginning of FFTL. We illustrate how these parameters can also be estimated from FFTL data.
Mukhopadhyay, S.; Tsang, Y.; Finsterle, S.
Enhanced Geothermal Systems Research and Development: Models of Subsurface Chemical Processes Affecting Fluid Flow
Successful exploitation of the vast amount of heat stored beneath the earth�s surface in hydrothermal and fluid-limited, low permeability geothermal resources would greatly expand the Nation�s domestic energy inventory and thereby promote a more secure energy supply, a stronger economy and a cleaner environment. However, a major factor limiting the expanded development of current hydrothermal resources as well as the production of enhanced geothermal systems (EGS) is insufficient knowledge about the chemical processes controlling subsurface fluid flow. With funding from past grants from the DOE geothermal program and other agencies, we successfully developed advanced equation of state (EOS) and simulation technologies that accurately describe the chemistry of geothermal reservoirs and energy production processes via their free energies for wide XTP ranges. Using the specific interaction equations of Pitzer, we showed that our TEQUIL chemical models can correctly simulate behavior (e.g., mineral scaling and saturation ratios, gas break out, brine mixing effects, down hole temperatures and fluid chemical composition, spent brine incompatibilities) within the compositional range (Na-K-Ca-Cl-SO4-CO3-H2O-SiO2-CO2(g)) and temperature range (T < 350�C) associated with many current geothermal energy production sites that produce brines with temperatures below the critical point of water. The goal of research carried out under DOE grant DE-FG36-04GO14300 (10/1/2004-12/31/2007) was to expand the compositional range of our Pitzer-based TEQUIL fluid/rock interaction models to include the important aluminum and silica interactions (T < 350�C). Aluminum is the third most abundant element in the earth�s crust; and, as a constituent of aluminosilicate minerals, it is found in two thirds of the minerals in the earth�s crust. The ability to accurately characterize effects of temperature, fluid mixing and interactions between major rock-forming minerals and hydrothermal and/or injected fluids is critical to predict important chemical behaviors affecting fluid flow, such as mineral precipitation/dissolution reactions. We successfully achieved the project goal and objectives by demonstrating the ability of our modeling technology to correctly predict the complex pH dependent solution chemistry of the Al3+ cation and its hydrolysis species: Al(OH)2+, Al(OH)2+, Al(OH)30, and Al(OH)4- as well as the solubility of common aluminum hydroxide and aluminosilicate minerals in aqueous brines containing components (Na, K, Cl) commonly dominating hydrothermal fluids. In the sodium chloride system, where experimental data for model parameterization are most plentiful, the model extends to 300�C. Determining the stability fields of aluminum species that control the solubility of aluminum-containing minerals as a function of temperature and composition has been a major objective of research in hydrothermal chemistry.
Moller, Nancy; Weare J. H.
Fluid flow monitoring device
DOE Patents [OSTI]
A flow meter and temperature measuring device are described comprising a tube with a body centered therein for restricting flow and a sleeve at the upper end of the tube to carry several channels formed longitudinally in the sleeve to the appropriate axial location where they penetrate the tube to allow pressure measurements and temperature measurements with thermocouples. The high pressure measurement is made using a channel penetrating the tube away from the body and the low pressure measurement is made at a location at the widest part of the body. An end plug seals the end of the device and holes at its upper end allow fluid to pass from the interior of the tube into a plenum. The channels are made by cutting grooves in the sleeve, the grooves widened at the surface of the sleeve and then a strip of sleeve material is welded to the grooves closing the channels. Preferably the sleeve is packed with powdered graphite before cutting the grooves and welding the strips. 7 figures.
McKay, M.D.; Sweeney, C.E.; Spangler, B.S. Jr.
A flow meter and temperature measuring device comprising a tube with a body centered therein for restricting flow and a sleeve at the upper end of the tube to carry several channels formed longitudinally in the sleeve to the appropriate axial location where they penetrate the tube to allow pressure measurements and temperature measurements with thermocouples. The high pressure measurement is made using a channel penetrating the tube away from the body and the low pressure measurement is made at a location at the widest part of the body. An end plug seals the end of the device and holes at its upper end allow fluid to pass from the interior of the tube into a plenum. The channels are made by cutting grooves in the sleeve, the grooves widened at the surface of the sleeve and then a strip of sleeve material is welded to the grooves closing the channels. Preferably the sleeve is packed with powdered graphite before cutting the grooves and welding the strips.
McKay, Mark D. (1426 Socastee Dr., North Augusta, SC 29841); Sweeney, Chad E. (3600 Westhampton Dr., Martinez, GA 30907-3036); Spangler, Jr., B. Samuel (2715 Margate Dr., Augusta, GA 30909)
Update and assessment of geothermal economic models, geothermal fluid flow and heat distribution models, and geothermal data bases
Numerical simulation models and data bases that were developed for DOE as part of a number of geothermal programs have been assessed with respect to their overall stage of development and usefulness. This report combines three separate studies that focus attention upon: (1) economic models related to geothermal energy; (2) physical geothermal system models pertaining to thermal energy and the fluid medium; and (3) geothermal energy data bases. Computerized numerical models pertaining to the economics of extracting and utilizing geothermal energy have been summarized and catalogued with respect to their availability, utility and function. The 19 models that are discussed in detail were developed for use by geothermal operators, public utilities, and lending institutions who require a means to estimate the value of a given resource, total project costs, and the sensitivity of these values to specific variables. A number of the models are capable of economically assessing engineering aspects of geothermal projects. Computerized simulations of heat distribution and fluid flow have been assessed and are presented for ten models. Five of the models are identified as wellbore simulators and five are described as reservoir simulators. Each model is described in terms of its operational characteristics, input, output, and other pertinent attributes. Geothermal energy data bases are reviewed with respect to their current usefulness and availability. Summaries of eight data bases are provided in catalogue format, and an overall comparison of the elements of each data base is included.
Kenkeremath, D. (ed.)
Fast and Informative Flow Simulations in a Building by Using Fast Fluid Dynamics Model on Graphics Processing Unit
Fast and Informative Flow Simulations in a Building by Using Fast Fluid Dynamics Model on Graphics solve Navier-Stokes equations and other transportation equations for energy and species at a speed of 50 it in parallel on a Graphics Processing Unit (GPU). This study validated the FFD on the GPU by simulating
Chen, Qingyan "Yan"
Insertable fluid flow passage bridgepiece and method
A fluid flow passage bridgepiece for insertion into an open-face fluid flow channel of a fluid flow plate is provided. The bridgepiece provides a sealed passage from a columnar fluid flow manifold to the flow channel, thereby preventing undesirable leakage into and out of the columnar fluid flow manifold. When deployed in the various fluid flow plates that are used in a Proton Exchange Membrane (PEM) fuel cell, bridgepieces of this invention prevent mixing of reactant gases, leakage of coolant or humidification water, and occlusion of the fluid flow channel by gasket material. The invention also provides a fluid flow plate assembly including an insertable bridgepiece, a fluid flow plate adapted for use with an insertable bridgepiece, and a method of manufacturing a fluid flow plate with an insertable fluid flow passage bridgepiece.
Jones, Daniel O. (Glenville, NV)
Numerical modeling of fluid flow and time-lapse seismics to monitor ...
May 30, 2014 ... and saturation. The model considers the geometrical features of the formations, .... mudstone layers inside the Utsira formation the complex bulk and shear ..... obtained from the flow simulator to build a 2D model of the Utsira.
Computational fluid dynamics modeling of two-phase flow in a BWR fuel assembly. Final CRADA Report.
A direct numerical simulation capability for two-phase flows with heat transfer in complex geometries can considerably reduce the hardware development cycle, facilitate the optimization and reduce the costs of testing of various industrial facilities, such as nuclear power plants, steam generators, steam condensers, liquid cooling systems, heat exchangers, distillers, and boilers. Specifically, the phenomena occurring in a two-phase coolant flow in a BWR (Boiling Water Reactor) fuel assembly include coolant phase changes and multiple flow regimes which directly influence the coolant interaction with fuel assembly and, ultimately, the reactor performance. Traditionally, the best analysis tools for this purpose of two-phase flow phenomena inside the BWR fuel assembly have been the sub-channel codes. However, the resolution of these codes is too coarse for analyzing the detailed intra-assembly flow patterns, such as flow around a spacer element. Advanced CFD (Computational Fluid Dynamics) codes provide a potential for detailed 3D simulations of coolant flow inside a fuel assembly, including flow around a spacer element using more fundamental physical models of flow regimes and phase interactions than sub-channel codes. Such models can extend the code applicability to a wider range of situations, which is highly important for increasing the efficiency and to prevent accidents.
Tentner, A.; Nuclear Engineering Division
Non-Newtonian fluid flow
zero and unity. The Ostwald- de Waele Equation (4), commonly known as the power law, is sometimes used to describe fluid behavior of this type. The rheological equation is (4) where the parameters "k" and "n" are constant for a particular fluid... be extended to include Reynolds numbers and the type of flow determined to be laminar and/or turbulent. It is assumed that the transition from laminar to turbulent flow occurs at a Reynolds number of 2100, the numeric distribution of Reynolds numbers...
Osinski, Charles Anthony
Development of an equivalent homogenous fluid model for pseudo-two-phase (air plus water) flow through fractured rock
Fracture flow of two-phase mixtures is particularly applicable to the coal mining and coal bed methane projects in Australia. A one-dimensional steady-state pseudo-two-phase flow model is proposed for fractured rock. The model considers free flow of a compressible mixture of air and water in an inclined planar fracture and is based upon the conservation of momentum and the 'cubic' law. The flow model is coupled to changes in the stress environment through the fracture normal stiffness, which is related to changes in fracture aperture. The model represents the individual air and water phases as a single equivalent homogenous fluid. Laboratory testing was performed using the two-phase high-pressure triaxial apparatus on 54 mm diameter (approximately 2: 1 height: diameter) borehole cores intersected by induced near-axial fractures. The samples were of Triassic arenaceous fine-medium grained sandstone (known as the Eckersley Formation) that is found locally in the Southern Coalfield of New South Wales. The sample fracture roughness was assessed using a technique based upon Fourier series analysis to objectively attribute a joint roughness coefficient. The proposed two-phase flow model was verified using the recorded laboratory data obtained over a range of triaxial confining pressures (i.e., fracture normal stresses).
Price, J.; Indraratna, B. [University of Wollongong, Wollongong, NSW (Australia). School of Civil Engineering
Fluid Gravity Engineering Rocket motor flow analysis
Fluid Gravity Engineering Capability · Rocket motor flow analysis -Internal (performance) -External young scientists/engineers Fluid Gravity Engineering Ltd #12;
Anand, Mahesh
This is a 1D model of an active magnetic regenerative refrigerator (AMRR) that was developed in MATLAB. The model uses cycle inputs such as the fluid mass flow and
to the fluid-mechanical-magnetic processes associated with the cycle implementation. The interface between in MATLAB. The model uses cycle inputs such as the fluid mass flow and magnetic field profiles, fluid temperature profile of the fluid and regenerator. Using the temperature profiles, the cooling load produced
Wisconsin at Madison, University of
Nanometer-scale imaging and pore-scale fluid flow modeling inchalk
For many rocks of high economic interest such as chalk,diatomite, tight gas sands or coal, nanometer scale resolution is neededto resolve the 3D-pore structure, which controls the flow and trapping offluids in the rocks. Such resolutions cannot be achieved with existingtomographic technologies. A new 3D imaging method, based on serialsectioning and using the Focused Ion Beam (FIB) technology has beendeveloped. FIB allows for the milling of layers as thin as 10 nanometersby using accelerated Ga+ ions to sputter atoms from the sample surface.After each milling step, as a new surface is exposed, a 2D image of thissurface is generated. Next, the 2D images are stacked to reconstruct the3D pore or grain structure. Resolutions as high as 10 nm are achievableusing this technique. A new image processing method uses directmorphological analysis of the pore space to characterize thepetrophysical properties of diverse formations. In addition to estimationof the petrophysical properties (porosity, permeability, relativepermeability and capillary pressures), the method is used for simulationof fluid displacement processes, such as those encountered in variousimproved oil recovery (IOR) approaches. Computed with the new methodcapillary pressure curves are in good agreement with laboratory data. Themethod has also been applied for visualization of the fluid distributionat various saturations from the new FIB data.
Tomutsa, Liviu; Silin, Dmitriy; Radmilovich, Velimir
Transient fluid and heat flow modeling in coupled wellbore/reservoir systems
....................................................... 66 5.3.1 Modeling Field Data ..................................................................... 68 5.3.2 Optimal Location of Permanent Downhole Gauge....................... 71 5.4 Effect of Gauge Location on Pressure-Transient Analysis... at the midpoint of the flow string................................. 70 Figure 5.26 Downhole gauge placement configurations .............................................. 71 Figure 5.27 Temperature and density profiles in the wellbore...
Izgec, Bulent
SEISMIC MONITORING OF CARBON DIOXIDE FLUID FLOW J. E. Santos1, G. B. Savioli2, J. M. Carcione3, D´e, Argentina SEISMIC MONITORING OF CARBON DIOXIDE FLUID FLOW p. #12;Introduction. I Storage of CO2). SEISMIC MONITORING OF CARBON DIOXIDE FLUID FLOW p. #12;Introduction. II CO2 is separated from natural
Santos, Juan
Momentum spectra, anisotropic flow, and ideal fluids
If the matter produced in ultrarelativistic heavy-ion collisions reaches thermal equilibrium, its subsequent evolution follows the laws of ideal fluid dynamics. We show that general predictions can be made on this basis alone, irrespective of the details of the hydrodynamical model. We derive several scaling rules for momentum spectra and anisotropic flow (in particular the elliptic flow, v2, and the hexadecupole flow, v4) of identified particles. Comparison with existing data is briefly discussed, and qualitative predictions are made for LHC.
N. Borghini; J. -Y. Ollitrault
Fluid Flow Simulation in Fractured Reservoirs
The purpose of this study is to analyze fluid flow in fractured reservoirs. In most petroleum reservoirs, particularly carbonate reservoirs and some tight sands, natural fractures play a critical role in controlling fluid ...
Computational Fluid Dynamics Modeling of the Bonneville Project: Tailrace Spill Patterns for Low Flows and Corner Collector Smolt Egress
In 2003, an extension of the existing ice and trash sluiceway was added at Bonneville Powerhouse 2 (B2). This extension started at the existing corner collector for the ice and trash sluiceway adjacent to Bonneville Powerhouse 2 and the new sluiceway was extended to the downstream end of Cascade Island. The sluiceway was designed to improve juvenile salmon survival by bypassing turbine passage at B2, and placing these smolt in downstream flowing water minimizing their exposure to fish and avian predators. In this study, a previously developed computational fluid dynamics model was modified and used to characterized tailrace hydraulics and sluiceway egress conditions for low total river flows and low levels of spillway flow. STAR-CD v4.10 was used for seven scenarios of low total river flow and low spill discharges. The simulation results were specifically examined to look at tailrace hydraulics at 5 ft below the tailwater elevation, and streamlines used to compare streamline pathways for streamlines originating in the corner collector outfall and adjacent to the outfall. These streamlines indicated that for all higher spill percentage cases (25% and greater) that streamlines from the corner collector did not approach the shoreline at the downstream end of Bradford Island. For the cases with much larger spill percentages, the streamlines from the corner collector were mid-channel or closer to the Washington shore as they moved downstream. Although at 25% spill at 75 kcfs total river, the total spill volume was sufficient to "cushion" the flow from the corner collector from the Bradford Island shore, areas of recirculation were modeled in the spillway tailrace. However, at the lowest flows and spill percentages, the streamlines from the B2 corner collector pass very close to the Bradford Island shore. In addition, the very flow velocity flows and large areas of recirculation greatly increase potential predator exposure of the spillway passed smolt. If there is concern for egress issues for smolt passing through the spillway, the spill pattern and volume need to be revisited.
Rakowski, Cynthia L.; Serkowski, John A.; Richmond, Marshall C.; Perkins, William A.
Process for retarding fluid flow
A process is described for retarding the flow of fluid in a subterranean formation, comprising: (a) introducing an effective amount of a gel-forming composition into a subterranean formation, the gel-forming composition being operable when gelled in the formation for retarding the flow of fluid therein. The gel-forming composition consists of: i. a first substance dissolved in water to form an aqueous solution, the first substance being selected from the group consisting of polyvivyl alcohols, and mixtures thereof, wherein the gel-forming composition contains an amount of the first substance of from about 0.5 to about 5 weight percent of the gel-forming composition, and ii. an effective amount of glutaraldehyde which is operable for forming a weakly acidic condition having a pH from about 5.5 to less than 7 in the gel-forming composition and also operable for promoting crosslinking of the first substance and glutaraldehyde and for forming a gel from the gel-forming composition under the weakly acidic condition within a period of time no greater than about 5 days without adding an acidic catalyst to the gel-forming composition to lower the pH of the gel-forming composition below about 5.5.
Sandford, B.B.; Zillmer, R.C.
Characterizing fractured rock for fluid-flow, geomechanical, and paleostress modeling: Methods and preliminary results from Yucca Mountain, Nevada
Fractures have been characterized for fluid-flow, geomechanical, and paleostress modeling at three localities in the vicinity of drill hole USW G-4 at Yucca Mountain in southwestern Nevada. A method for fracture characterization is introduced that integrates mapping fracture-trace networks and quantifying eight fracture parameters: trace length, orientation, connectivity, aperture, roughness, shear offset, trace-length density, and mineralization. A complex network of fractures was exposed on three 214- to 260-m 2 pavements cleared of debris in the upper lithophysal unit of the Tiva Canyon Member of the Miocene Paint-brush Tuff. The pavements are two-dimensional sections through the three-dimensional network of strata-bound fractures. All fractures with trace lengths greater than 0.2 m were mapped and studied.
Barton, C.C.; Larsen, E.; Page, W.R.; Howard, T.M.
SEISMIC MONITORING OF. CARBON DIOXIDE FLUID FLOW. J. E. Santos. 1. , G. B. Savioli. 2. , J. M. Carcione. 3. , D. Gei. 3. 1. CONICET, IGPUBA, Fac.
A computational model for viscous fluid flow, heat transfer, and melting in in situ vitrification melt pools
MAGMA is a FORTRAN computer code designed to viscous flow in in situ vitrification melt pools. It models three-dimensional, incompressible, viscous flow and heat transfer. The momentum equation is coupled to the temperature field through the buoyancy force terms arising from the Boussinesq approximation. All fluid properties, except density, are assumed variable. Density is assumed constant except in the buoyancy force terms in the momentum equation. A simple melting model based on the enthalpy method allows the study of the melt front progression and latent heat effects. An indirect addressing scheme used in the numerical solution of the momentum equation voids unnecessary calculations in cells devoid of liquid. Two-dimensional calculations can be performed using either rectangular or cylindrical coordinates, while three-dimensional calculations use rectangular coordinates. All derivatives are approximated by finite differences. The incompressible Navier-Stokes equations are solved using a new fully implicit iterative technique, while the energy equation is differenced explicitly in time. Spatial derivatives are written in conservative form using a uniform, rectangular, staggered mesh based on the marker and cell placement of variables. Convective terms are differenced using a weighted average of centered and donor cell differencing to ensure numerical stability. Complete descriptions of MAGMA governing equations, numerics, code structure, and code verification are provided. 14 refs.
McHugh, P.R.; Ramshaw, J.D.
of filled polymers, and concentrated suspensions in screw extruders and dies of complex shapes is undertaken-dimensional flows including flows through dies, single/twin-screw extruders and other processing geometries m o n p * (1b) where Rs is the screw radius of the twin screw extruder preceding the die
Modeling fluid flow through single fracture using experimental, stochastic, and simulation approaches
This research presents an approach to accurately simulate flow experiments through a fractured core using experimental, stochastic, and simulation techniques. Very often, a fracture is assumed as a set of smooth parallel plates separated by a...
Alfred, Dicman
A Site-Scale Model For Fluid And Heat Flow In The Unsaturated...
Open Energy Info (EERE)
surface infiltration, and geothermal conditions are incorporated into the model. The reliability and accuracy of the model have been the subject of a comprehensive model...
Robust processing of optical flow of fluids Ashish Doshi and Adrian G. Bors, Senior Member, IEEE
the computational fluid dynamics (CFD). Navier-Stokes equations have been extensively studied in fluid mechanics Terms--Optical flow of fluids, computational fluid dy- namics, diffusion, vortex detection I displaying fluid movement. Velocity fields, characterizing the motion of fluids can be modelled using
Bors, Adrian
Preferential mode of gas invasion in sediments : grain-scale model of coupled multiphase fluid flow and sediment mechanics
We present a discrete element model for simulating, at the grain scale, gas migration in brine-saturated deformable media. We rigorously account for the presence of two fluids in the pore space by incorporating forces on ...
Jain, Antone Kumar
Application of Neutron Imaging and Scattering to Fluid Flow and...
Application of Neutron Imaging and Scattering to Fluid Flow and Fracture in EGS Environments Application of Neutron Imaging and Scattering to Fluid Flow and Fracture in EGS...
Fracture Network and Fluid Flow Imaging for EGS Applications...
Fracture Network and Fluid Flow Imaging for EGS Applications from Multi-Dimensional Electrical Resistivity Structure Fracture Network and Fluid Flow Imaging for EGS Applications...
Fluid flow control with transformation media
We introduce a new concept for the manipulation of fluid flow around three-dimensional bodies. Inspired by transformation optics, the concept is based on a mathematical idea of coordinate transformations, and physically implemented with anisotropic porous media permeable to the flow of fluids. In two different situations - for an impermeable object situated either in a free-flowing fluid or in a fluid-filled porous medium - we show that the object can be coated with a properly chosen inhomogeneous, anisotropic permeable medium, such as to preserve the streamlines of flow and the pressure distribution that would have existed in the absence of the object. The proposed fluid flow cloak completely eliminates any disturbance of the flow by the object, including the downstream wake. Consequently, the structure helps prevent the onset of turbulence by keeping the flow laminar even above the typical critical Reynolds number for the object of the same shape and size. The cloak also cancels the viscous drag force. This...
Urzhumov, Yaroslav A
Transient Temperature Modeling For Wellbore Fluid Under Static and Dynamic Conditions
for geothermal wells and prediction of injection fluid temperatures. In this thesis, development and usage of three models for transient fluid temperature are presented. Two models predict transient temperature of flowing fluid under separate flow configurations...
Ali, Muhammad
Directed flow fluid rinse trough
Novel rinse troughs accomplish thorough uniform rinsing. The tanks are suitable for one or more essentially planar items having substantially the same shape. The troughs ensure that each surface is rinsed uniformly. The new troughs also require less rinse fluid to accomplish a thorough rinse than prior art troughs.
Kempka, Steven N. (9504 Lona La., Albuquerque, NM 87111); Walters, Robert N. (11872 LaGrange St., Boise, ID 83709)
Novel rinse troughs accomplish thorough uniform rinsing. The tanks are suitable for one or more essentially planar items having substantially the same shape. The troughs ensure that each surface is rinsed uniformly. The new troughs also require less rinse fluid to accomplish a thorough rinse than prior art troughs. 9 figs.
Kempka, S.N.; Walters, R.N.
Flow control techniques for real-time media applications in best-effort networks using fluid models
at the application layer. An end-to-end ?uid model is used, including the source bu?er, the network and the destination bu?er. Traditional con- trol techniques, along with more advanced adaptive predictive control methods, are considered in order to provide... OF THE END-TO-END FLOW TRANSPORT SYSTEM : : : : : : : : : : : : : : : : : : : : : : 25 A. Source Bu?er Model . . . . . . . . . . . . . . . . . . . . . 25 B. Network Dynamic Model . . . . . . . . . . . . . . . . . . . 27 1. Time-Varying Time Delay Model...
Konstantinou, Apostolos
Numerical simulation of fluid flow in porous/fractured media
Theoretical models of fluid flow in porous/fractured media can help in the design of in situ fossil energy and mineral extraction technologies. Because of the complexity of these processes, numerical solutions are usually required. Sample calculations illustrate the capabilities of present day computer models.
Travis B.J.; Cook, T.L.
Method and apparatus for controlling fluid flow
A method and apparatus for precisely controlling the rate (and hence amount) of fluid flow are given. The controlled flow rate is finely adjustable, can be extremely small (on the order of microliter-atmospheres per second), can be adjusted to zero (flow stopped), and is stable to better than 1% with time. The dead volume of the valve can be made arbitrarily small, in fact essentially zero. The valve employs no wearing mechanical parts (including springs, stems, or seals). The valve is finely adjustable, has a flow rate dynamic range of many decades, can be made compatible with any fluid, and is suitable for incorporation into an open or closed loop servo-control system.
Miller, J.R.
Newtonian fluid flow through Microfabricated Hyperbolic Contractions
spraying (Barnes et al. 1989). Optimization of these processes requires accurate measurements for measurement of extensional viscosity involves studying the fluid flow through contractions profiled to give extensional viscosity. To remove the effect of shear at the walls of contractions Shaw (1975) proposed the use
Separation of particles from gaseous fluid flows
In a gas washer and similar separator devices which utilize stationary wall means to deflect a gas flow and to subject the same to centrifugal force for continuously separating out foreign particulate matter which is collected on or adjacent the stationary wall means, the invention provides spirally curved laminae constituting the stationary wall means and co-operating to define passage means, at least a part of which has a cross-section which first narrows and then widens in the direction of fluid flow and which is also curved spirally first in one and then in the opposite direction. Nozzle means may be arranged to feed moisture into the fluid flow to assist wet separation, and by electrically insulating conductive laminae from one another, the invention may also be used as an electrostatic precipitator.
Paul, E.; Reither, K.
Ultrasonic fluid flow measurement method and apparatus
An apparatus for measuring the flow of a fluid in a pipe using ultrasonic waves. The apparatus comprises an ultrasonic generator, a lens for focusing the sound energy produced by the generator, and means for directing the focused energy into the side of the pipe through an opening and in a direction close to parallel to the long axis of the pipe. A cone carries the sound energy to the lens from the generator. Depending on the choice of materials, there may be a quarter-wave, acoustic impedance matching section between the generator and the cone to reduce the reflections of energy at the cone boundary. The lens material has an acoustic impedance similar to that of the cone material but a different sonic velocity so that the lens can converge the sound waves in the fluid. A transition section between the lens and the fluid helps to couple the energy to the fluid and assures it is directed as close to parallel to the fluid flow direction as possible.
Kronberg, James W. (108 Independent Blvd., Aiken, SC 29801)
An apparatus for measuring the flow of a fluid in a pipe using ultrasonic waves. The apparatus comprises an ultrasonic generator, a lens for focusing the sound energy produced by the generator, and means for directing the focused energy into the side of the pipe through an opening and in a direction close to parallel to the long axis of the pipe. A cone carries the sound energy to the lens from the generator. Depending on the choice of materials, there may be a quarter-wave, acoustic impedance matching section between the generator and the cone to reduce the reflections of energy at the cone boundary. The lens material has an acoustic impedance similar to that of the cone material but a different sonic velocity so that the lens can converge the sound waves in the fluid. A transition section between the lens and the fluid helps to couple the energy to the fluid and assures it is directed as close to parallel to the fluid flow direction as possible. 3 figures.
Kronberg, J.W.
Thermodynamic Model for Fluid-Fluid Interfacial Areas in Porous...
(free) and isolated (entrapped) nonwetting fluids. The model is restricted to two-fluid systems in which (1) no significant conversion of mechanical work into heat occurs,...
The Effects of Fluid Flow On Shear Localization and Frictional Strength From Dynamic Models Of Fault Gouge During Earthquakes
have an increased localization toward the boundaries of the gouge layer (type III), and no occurrence of distributed (type I) shear. Systems with lower N and k show liquefaction events. Liquefaction events originate from increases in fluid pressure...
Bianco, Ronald
Fluid breakup during simultaneous two-phase flow through a three-dimensional porous medium
We use confocal microscopy to directly visualize the simultaneous flow of both a wetting and a non-wetting fluid through a model three-dimensional (3D) porous medium. We find that, for small flow rates, both fluids flow through unchanging, distinct, connected 3D pathways; in stark contrast, at sufficiently large flow rates, the non-wetting fluid is broken up into discrete ganglia. By performing experiments over a range of flow rates, using fluids of different viscosities, and with porous media having different geometries, we show that this transition can be characterized by a state diagram that depends on the capillary numbers of both fluids, suggesting that it is controlled by the competition between the viscous forces exerted on the flowing oil and the capillary forces at the pore scale. Our results thus help elucidate the diverse range of behaviors that arise in two-phase flow through a 3D porous medium.
Sujit S. Datta; Jean-Baptiste Dupin; David A. Weitz
Multiphase fluid flow and time lapse seismics
Time-lapse seismic surveys aim to monitor the migration and dispersal of the CO2 ... of CO2-brine flow and seismic wave propagation to model and monitor CO2�...
Thermal-fluid and electrochemical modeling and performance study of a planar solid oxide electrolysis cell : analysis on SOEC resistances, size, and inlet flow conditions.
Argonne National Laboratory and Idaho National Laboratory researchers are analyzing the electrochemical and thermal-fluid behavior of solid oxide electrolysis cells (SOECs) for high temperature steam electrolysis using computational fluid dynamics (CFD) techniques. The major challenges facing commercialization of steam electrolysis technology are related to efficiency, cost, and durability of the SOECs. The goal of this effort is to guide the design and optimization of performance for high temperature electrolysis (HTE) systems. An SOEC module developed by FLUENT Inc. as part of their general CFD code was used for the SOEC analysis by INL. ANL has developed an independent SOEC model that combines the governing electrochemical mechanisms based on first principals to the heat transfer and fluid dynamics in the operation of SOECs. The ANL model was embedded into the commercial STAR-CD CFD software, and is being used for the analysis of SOECs by ANL. The FY06 analysis performed by ANL and reported here covered the influence of electrochemical properties, SOEC component resistances and their contributing factors, SOEC size and inlet flow conditions, and SOEC flow configurations on the efficiency and expected durability of these systems. Some of the important findings from the ANL analysis are: (1) Increasing the inlet mass flux while going to larger cells can be a compromise to overcome increasing thermal and current density gradients while increasing the cell size. This approach could be beneficial for the economics of the SOECs; (2) The presence of excess hydrogen at the SOEC inlet to avoid Ni degradation can result in a sizeable decrease in the process efficiency; (3) A parallel-flow geometry for SOEC operation (if such a thing be achieved without sealing problems) yields smaller temperature gradients and current density gradients across the cell, which is favorable for the durability of the cells; (4) Contact resistances can significantly influence the total cell resistance and cell temperatures over a large range of operating potentials. Thus it is important to identify and avoid SOEC stack conditions leading to such high resistances due to poor contacts.
Yildiz, B.; Smith, J.; Sofu, T.; Nuclear Engineering Division
Using Euler-Lagrange Variational Principle to Obtain Flow Relations for Generalized Newtonian Fluids
Euler-Lagrange variational principle is used to obtain analytical and numerical flow relations in cylindrical tubes. The method is based on minimizing the total stress in the flow duct using the fluid constitutive relation between stress and rate of strain. Newtonian and non-Newtonian fluid models; which include power law, Bingham, Herschel-Bulkley, Carreau and Cross; are used for demonstration.
Taha Sochi
Use of Geophysical Techniques to Characterize Fluid Flow in a...
to Geothermal Prospecting Joint inversion of electrical and seismic data for Fracture char. and Imaging of Fluid Flow in Geothermal Systems Use of Geophysical Techniques...
Fracture Network and Fluid Flow Imaging for EGS Applications from Multi-Dimensional Electrical Resistivity Structure Principal Investigator: Philip E. Wannamaker University of Utah...
Network and Fluid Flow Imaging for EGS Applications from Multi-Dimensional Electrical Resistivity Structure Principal Investigator: Philip E. Wannamaker University of Utah Energy &...
and test combined geophysical techniques to characterize fluid flow, in relation to fracture orientations and fault distributions in a geothermal system. Average Overall Score:...
Dispersed Fluid Flow in Fractured Reservoirs- an Analysis of...
correlations. Downhole measurements of the tracer response exiting from discrete fracture zones permit further characterization of reservoir fluid flow behavior. Tracer...
Electromagnetic Radiations as a Fluid Flow
We combine Maxwell's equations with Eulers's equation, related to a velocity field of an immaterial fluid, where the density of mass is replaced by a charge density. We come out with a differential system able to describe a relevant quantity of electromagnetic phenomena, ranging from classical dipole waves to solitary wave-packets with compact support. The clue is the construction of an energy tensor summing up both the electromagnetic stress and a suitable mass tensor. With this right-hand side, explicit solutions of the full Einstein's equation are computed for a wide class of wave phenomena. Since our electromagnetic waves may behave and interact exactly as a material fluid, they can create vortex structures. We then explicitly analyze some vortex ring configurations and examine the possibility to build a model for the electron.
Daniele Funaro
Device for deriving energy from a flow of fluid
Improved process and device for extracting energy present in a flowing fluid medium wherein a supported hub with propellers or blades is placed in said medium and the blades are provided with a wing or vane at the tip. The wing is of such a form that it generates a ''venturi effect'' in the flowing medium by which a part of the fluid which should normally pass outside the propeller disc area, is drawn into the propeller. The improvement consists of mixing of fluid which normally should pass outside the venturi with fluid which has flowed through the blades by provisions on blades and/or wing or vanes.
van Holten, T.
Numerical modeling of time-lapse seismic data from fractured reservoirs including fluid flow and geochemical processes
orthogonal sets of fractures in most subsurface rocks that can be converted to seismic model, similar to DFN study. The quality and validity of the models is assessed by comparisons to DFN models, including calculations of fractal dimension measures that can...
Shekhar, Ravi
Analysis of multiphase fluid flows via high speed and synthetic aperture three dimensional imaging
Spray flows are a difficult problem within the realm of fluid mechanics because of the complicated interfacial physics involved. Complete models of sprays having even the simplest geometries continue to elude researchers ...
Scharfman, Barry Ethan
Method and apparatus for chemically altering fluids in continuous flow
The present invention relates to a continuous flow fluid reactor for chemically altering fluids. The reactor operates on standard frequency (50 to 60 Hz) electricity. The fluid reactor contains particles that are energized by the electricity to form a corona throughout the volume of the reactor and subsequently a non-equilibrium plasma that interacts with the fluid. Particles may form a fixed bed or a fluid bed. Electricity may be provided through electrodes or through an inductive coil. Fluids include gases containing exhaust products and organic fuels requiring oxidation.
Heath, William O. (Richland, WA); Virden, Jr., Judson W. (Richland, WA); Richardson, R. L. (West Richland, WA); Bergsman, Theresa M. (Richland, WA)
The present invention relates to a continuous flow fluid reactor for chemically altering fluids. The reactor operates on standard frequency (50 to 60 Hz) electricity. The fluid reactor contains particles that are energized by the electricity to form a corona throughout the volume of the reactor and subsequently a non-equilibrium plasma that interacts with the fluid. Particles may form a fixed bed or a fluid bed. Electricity may be provided through electrodes or through an inductive coil. Fluids include gases containing exhaust products and organic fuels requiring oxidation. 4 figures.
Heath, W.O.; Virden, J.W. Jr.; Richardson, R.L.; Bergsman, T.M.
Maxwell's fluid model of magnetism
In 1861, Maxwell derived two of his equations of electromagnetism by modelling a magnetic line of force as a `molecular vortex' in a fluid-like medium. Later, in 1980, Berry and colleagues conducted experiments on a `phase vortex', a wave geometry in a fluid which is analogous to a magnetic line of force and also exhibits behaviour corresponding to the quantisation of magnetic flux. Here we unify these approaches by writing down a solution to the equations of motion for a compressible fluid which behaves in the same way as a magnetic line of force. We then revisit Maxwell's historical inspiration, namely Faraday's 1846 model of light as disturbances in lines of force. Using our unified model, we show that such disturbances resemble photons: they are polarised, absorbed discretely, obey Maxwell's full equations of electromagnetism to first order, and quantitatively reproduce the correlation that is observed in the Bell tests.
Robert Brady; Ross Anderson
Friction-Induced Fluid Heating in Nanoscale Helium Flows
We investigate the mechanism of friction-induced fluid heating in nanoconfinements. Molecular dynamics simulations are used to study the temperature variations of liquid helium in nanoscale Poiseuille flows. It is found that the fluid heating is dominated by different sources of friction as the external driving force is changed. For small external force, the fluid heating is mainly caused by the internal viscous friction in the fluid. When the external force is large and causes fluid slip at the surfaces of channel walls, the friction at the fluid-solid interface dominates over the internal friction in the fluid and is the major contribution to fluid heating. An asymmetric temperature gradient in the fluid is developed in the case of nonidentical walls and the general temperature gradient may change sign as the dominant heating factor changes from internal to interfacial friction with increasing external force.
Li Zhigang [Department of Mechanical Engineering, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon (Hong Kong)
Dynamic dielectric response of electrorheological fluids in drag and pressure flow
We have determined the response time of dilute electrorheological fluids (ER) in drag flow, in pressure-driven flow, and in the quiescent state from the dynamic dielectric response. The dependence of the response times on the electric field strength, the shear rate, and the flow velocity were investigated. In the case of ER fluids in drag flow, the response times were also determined from the stress response of the fluid measured simultaneously with the dielectric properties. Comparing the dielectric and rheological response times measured at the same conditions, a significant discrepancy was found, which was attributed to the different instrumental response times of the employed methods. The dielectric permittivity of the quiescent ER fluid was estimated on the basis of formulas derived from the Clausius-Mossotti equation. This simple theoretical model was extended and applied to ER fluids under shear to evaluate the experimental dielectric results.
B. Horv�th; I. Szalai
Implementation of surface tension with wall adhesion effects in a three-dimensional finite element model for fluid flow
- 1 - Implementation of surface tension with wall adhesion effects in a three-dimensional finite element modelling of surface tension. The external stress vectors associated with surface tension a drop of liquid on a plane is treated. Keywords : surface tension, finite element method, average
Shear-slip analysis in multiphase fluid-flow reservoir engineering ap plications using TOUGH-FLAC
IN MULTIPHASE FLUID-FLOW RESERVOIR ENGINEERING APPLICATIONSin multiphase fluid-flow reservoir-engineering applications.in multiphase fluid-flow reservoir engineering applications.
Rutqvist, Jonny; Birkholzer, Jens; Cappa, Frederic; Oldenburg, Curt; Tsang, Chin-Fu
FRACSTIM/I: A Fully Coupled Fluid Flow/Heat Transport and Geomechanica...
FRACSTIMI: A Fully Coupled Fluid FlowHeat Transport and Geomechanical DeformationFracture Generation Simulator FRACSTIMI: A Fully Coupled Fluid FlowHeat Transport and...
Imaging Fluid Flow in Geothermal Wells Using Distributed Thermal Perturbation Sensing
Imaging Fluid Flow in Geothermal Wells Using Distributed16 Imaging Fluid Flow in Geothermal Wells Using Distributedflow processes near a geothermal well under heating and
Freifeld, B.
Feedback regulated induction heater for a flowing fluid
A regulated induction heater for heating a stream of flowing fluid to a predetermined desired temperature. The heater includes a radiofrequency induction coil which surrounds a glass tube through which the fluid flows. A heating element consisting of a bundle of approximately 200 stainless steel capillary tubes located within the glass tube couples the output of the induction coil to the fluid. The temperature of the fluid downstream from the heating element is sensed with a platinum resistance thermometer, the output of which is applied to an adjustable porportional and integral feedback control circuit which regulates the power applied to the induction coil. The heater regulates the fluid temperature to within 0.005/sup 0/C at a flow rate of 50 cm/sup 3//sec with a response time of less than 0.1 second, and can accommodate changes in heat load up to 1500 watts.
Migliori, A.; Swift, G.W.
A regulated induction heater for heating a stream of flowing fluid to a predetermined desired temperature. The heater includes a radiofrequency induction coil which surrounds a glass tube through which the fluid flows. A heating element consisting of a bundle of approximately 200 stainless steel capillary tubes located within the glass tube couples the output of the induction coil to the fluid. The temperature of the fluid downstream from the heating element is sensed with a platinum resistance thermometer, the output of which is applied to an adjustable proportional and integral feedback control circuit which regulates the power applied to the induction coil. The heater regulates the fluid temperature to within 0.005.degree. C. at a flow rate of 50 cm.sup.3 /second with a response time of less than 0.1 second, and can accommodate changes in heat load up to 1500 watts.
Migliori, Albert (Santa Fe, NM); Swift, Gregory W. (Los Alamos, NM)
On the acceleration potential in perfect fluid flow
ON THE ACCELERATION POTENTIAL IN PERFECT FLUID FLOW A Thesis By RAYMOND RUDOLPH MAESTRI Submitted. to the Graduate School of the Agricultural and Mechanical College of Texas in partial fulfrllment of the requirements for the degree of MASTER... OF SCIENCE August, 1960 Department of Aeronautical Engineering Major Subject: Aeronautical Engineering ON THE ACCELERATION POTENTIAL IN PERFECT FLUID FLOW A Thesis RAYMOND RUDOLPH MAESTRI Approved as to style and content by: Chairman of Commit e...
Maestri, Raymond Rudolph
Numerical simulation of flow separation control by oscillatory fluid injection
NUMERICAL SIMULATION OF FLOW SEPARATION CONTROL BY OSCILLATORY FLUID INJECTION A Dissertation by CELERINO RESENDIZ ROSAS Submitted to the O?ce of Graduate Studies of Texas A&M University in partial ful?llment of the requirements for the degree... of DOCTOR OF PHILOSOPHY May 2005 Major Subject: Aerospace Engineering NUMERICAL SIMULATION OF FLOW SEPARATION CONTROL BY OSCILLATORY FLUID INJECTION A Dissertation by CELERINO RESENDIZ ROSAS Submitted to Texas A&M University in partial ful...
Resendiz Rosas, Celerino
1. Introduction Fluid flow in continuous casting of steel is of great inter-
-phase fluid flow owing to the simulation kinematic viscosity of steel and water, the flow pattern itself and entrainment of the mold slag, · transient fluctuations and waves in the top surface level, and their effect, such as intermixing during a grade change and segregation. Extensive past work has employed physical water models
Thomas, Brian G.
Journal of Fluids and Structures 24 (2008) 250269 Numerical and experimental study of expiratory flow
, the pharynx, the mouth and the larynx (Fig. 1), is the most external part of the respiratory system. Modelling deformations has been chosen to compute the mechanical behaviour of the tongue. The main features of the flow and Depollier, 1995; Huang, 1995; Balint and Lucey, 2005), numerical simulations of the respiratory fluid flow
Van Hirtum, Annemie
System and method measuring fluid flow in a conduit
A system for measuring fluid mass flow in a conduit in which there exists a pressure differential in the fluid between at least two spaced-apart locations in the conduit. The system includes a first pressure transducer disposed in the side of the conduit at a first location for measuring pressure of fluid at that location, a second or more pressure transducers disposed in the side of the conduit at a second location, for making multiple measurements of pressure of fluid in the conduit at that location, and a computer for computing the average pressure of the multiple measurements at the second location and for computing flow rate of fluid in the conduit from the pressure measurement by the first pressure transducer and from the average pressure calculation of the multiple measurements.
Ortiz, Marcos German (Idaho Falls, ID); Kidd, Terrel G. (Blackfoot, ID)
Advanced tomographic flow diagnostics for opaque multiphase fluids
This report documents the work performed for the ``Advanced Tomographic Flow Diagnostics for Opaque Multiphase Fluids`` LDRD (Laboratory-Directed Research and Development) project and is presented as the fulfillment of the LDRD reporting requirement. Dispersed multiphase flows, particularly gas-liquid flows, are industrially important to the chemical and applied-energy industries, where bubble-column reactors are employed for chemical synthesis and waste treatment. Due to the large range of length scales (10{sup {minus}6}-10{sup 1}m) inherent in real systems, direct numerical simulation is not possible at present, so computational simulations are forced to use models of subgrid-scale processes, the accuracy of which strongly impacts simulation fidelity. The development and validation of such subgrid-scale models requires data sets at representative conditions. The ideal measurement techniques would provide spatially and temporally resolved full-field measurements of the distributions of all phases, their velocity fields, and additional associated quantities such as pressure and temperature. No technique or set of techniques is known that satisfies this requirement. In this study, efforts are focused on characterizing the spatial distribution of the phases in two-phase gas-liquid flow and in three-phase gas-liquid-solid flow. Due to its industrial importance, the bubble-column geometry is selected for diagnostics development and assessment. Two bubble-column testbeds are utilized: one at laboratory scale and one close to industrial scale. Several techniques for measuring the phase distributions at conditions of industrial interest are examined: level-rise measurements, differential-pressure measurements, bulk electrical impedance measurements, electrical bubble probes, x-ray tomography, gamma-densitometry tomography, and electrical impedance tomography.
Torczynski, J.R.; O`Hern, T.J.; Adkins, D.R.; Jackson, N.B.; Shollenberger, K.A.
PAPER B3: PHYSICS OF FLUID FLOWS Hilary Term 2010
,...) · Aerodynamics important advances in fluid dynamics c. 1900 still active today · Lubrication of mechanical systems · Industry e.g. gases in pipes, polymer flows · Oil extraction liquids flowing through eff n, where `effective diameter' deff 0.3 nm, say. 2 �? 10-7 m = 200 nm. In FD, we consider scales
Read, Peter L.
The Flow of Newtonian Fluids in Axisymmetric Corrugated Tubes
This article deals with the flow of Newtonian fluids through axially-symmetric corrugated tubes. An analytical method to derive the relation between volumetric flow rate and pressure drop in laminar flow regimes is presented and applied to a number of simple tube geometries of converging-diverging nature. The method is general in terms of fluid and tube shape within the previous restrictions. Moreover, it can be used as a basis for numerical integration where analytical relations cannot be obtained due to mathematical difficulties.
Numerical and experimental study of expiratory flow in the case of major upper airway obstructions with fluid-structure interaction
and the larynx (fig. 1), is the most external part of the respiratory system. Modelling the fluid flow is described. The theory of linear elasticity in small deformations has been chosen to compute the mechanical of the respiratory fluid flow (Shome et al., 1998; Allen et al., 2004; Xu et al., 2006; Sung et al., 2006; Liu et al
Paris-Sud XI, Universit� de
Criteria for shear banding in time-dependent flows of complex fluids
Within a highly generalised theoretical framework for the flow properties of complex fluids, we study the onset of shear banding in the three most common time-dependent experimental protocols: step stress, step strain and shear startup. By means of a linear stability analysis we derive a fluid-universal criterion for the onset of banding, separately for each protocol, that depends only on the shape of the experimentally measured time-dependent rheological response function, independent of the constitutive law and internal state variables of the particular fluid in question. Our predictions thus have the same status, in these time-dependent flows, as the widely known criterion for banding in steady state (of negatively sloping shear stress vs. shear rate). We support them with simulations of the rolie-poly model of polymeric fluids, the soft glassy rheology model, and a fluidity model.
Robyn L. Moorcroft; Suzanne M. Fielding
Using x-ray microtomography and pore-scale modeling to quantify sediment mixing and fluid flow in a developing streambed
X-ray micro-tomography (XMT), image processing, and lattice Boltzmann (LB) methods were combined to observe sediment mixing, subsurface structure, and patterns of hydrogeological properties associated with bed sediment transport. Transport and mixing of sand and spherical glass beads were observed in a laboratory flume, beginning from a well-defined layered initial condition. Cores were obtained from the streambed at four different times, and each core was scanned by XMT in order to assess the evolution of spatial patterns within the bed. Image analysis clearly revealed the propagation of a sediment mixing front that began at the bed surface. The image data were used as boundary conditions in 3D LB simulation of pore fluid flow, showing that sediment sorting produced strong vertical gradients in permeability near the streambed surface. This new methodological approach offers potential for greatly improved characterization of mixing and transport of fine sediments in a wide variety of aquatic systems.
Chen, Cheng; Packman, Aaron I.; Gaillard, Jean-Francois; (NWU)
Similarity flow solutions of a non-Newtonian power-law fluid Mohamed Guedda, Zakia Hammouch
for a steady-state laminar bound- ary layer flow, governed by the Ostwald-de Wael power-law model-Newtonian fluid mechanics is the Ostwald-de Wael model (with a power-law rheology [2, 3, 4, 5, 6]), which
Paris-Sud XI, Université de
Investigation of Swirling Flow in Rod Bundle Subchannels Using Computational Fluid Dynamics
The fluid dynamics for turbulent flow through rod bundles representative of those used in pressurized water reactors is examined using computational fluid dynamics (CFD). The rod bundles of the pressurized water reactor examined in this study consist of a square array of parallel rods that are held on a constant pitch by support grids spaced axially along the rod bundle. Split-vane pair support grids are often used to create swirling flow in the rod bundle in an effort to improve the heat transfer characteristics for the rod bundle during both normal operating conditions and in accident condition scenarios. Computational fluid dynamics simulations for a two subchannel portion of the rod bundle were used to model the flow downstream of a split-vane pair support grid. A high quality computational mesh was used to investigate the choice of turbulence model appropriate for the complex swirling flow in the rod bundle subchannels. Results document a central swirling flow structure in each of the subchannels downstream of the split-vane pairs. Strong lateral flows along the surface of the rods, as well as impingement regions of lateral flow on the rods are documented. In addition, regions of lateral flow separation and low axial velocity are documented next to the rods. Results of the CFD are compared to experimental particle image velocimetry (PIV) measurements documenting the lateral flow structures downstream of the split-vane pairs. Good agreement is found between the computational simulation and experimental measurements for locations close to the support grid. (authors)
Holloway, Mary V. [United States Naval Academy, 117 Decatur Road, Annapolis, MD 21402-5018 (United States); Beasley, Donald E. [Clemson University, Clemson, S.C. 29634 (United States); Conner, Michael E. [Westinghouse Nuclear Fuel (United States)
Flow of fractal fluid in pipes: Non-integer dimensional space Vasily E. Tarasov
Flow of fractal fluid in pipes: Non-integer dimensional space approach Vasily E. Tarasov of an incompressible viscous fractal fluid in the pipe. Fractal fluid is described as a continuum in non solution for steady flow of fractal fluid in a pipe and corresponding fractal fluid discharge are suggested
Tarasov, Vasily E.
Development of an analytical model for organic-fluid fouling
The research goal of this project is to determine ways to effectively mitigate fouling in organic fluids: hydrocarbons and derived fluids. The fouling research focuses on the development of methodology for determining threshold conditions for fouling. Initially, fluid containing chemicals known to produce foulant is analyzed; subsequently, fouling of industrial fluids is investigated. The fouling model developed for determining the effects of physical parameters is the subject of this report. The fouling model is developed on the premise that the chemical reaction for generation of precursor can take place in the bulk fluid, in the thermal-boundary layer, or at the fluid/wall interface, depending upon the interactive effects of fluid dynamics, heat and mass transfer, and the controlling chemical reaction. In the analysis, the experimental data are examined for fouling deposition of polyperoxide produced by autoxidation of indene in kerosene. The effects of fluid and wall temperatures for two flow geometries are analyzed. The results show that the relative effects of physical parameters on the fouling rate differ for the three fouling mechanisms. Therefore, to apply the closed-flow-loop data to industrial conditions, the controlling mechanism must be identified.
Panchal, C.B.; Watkinson, A.P.
Two-Phase Fluid-Solid Flow Name of Supervisor: Dr D. Harris
in the fluid and the dispersion may be maintained by a fluid flow. There is a mechanical interaction between of discrete particles, (2) as a fluid, (3) as a dense gas and using the statistical mechanics of granular flowTwo-Phase Fluid-Solid Flow Name of Supervisor: Dr D. Harris Email: david
Sidorov, Nikita
Measurement Of The Fluid Flow Load On A Globe Valve Stem Under Various Cavitation
Measurement Of The Fluid Flow Load On A Globe Valve Stem Under Various Cavitation Conditions)" #12;Measurement Of The Fluid Flow Load On A Globe Valve Stem Under Various Cavitation Conditions, cavitation, fluid flow load, CFD. Abstract: The evaluation of fluid forces on the stem is important for wear
Characterization of fracture networks for fluid flow analysis
The analysis of fluid flow through fractured rocks is difficult because the only way to assign hydraulic parameters to fractures is to perform hydraulic tests. However, the interpretation of such tests, or ''inversion'' of the data, requires at least that we know the geometric pattern formed by the fractures. Combining a statistical approach with geophysical data may be extremely helpful in defining the fracture geometry. Cross-hole geophysics, either seismic or radar, can provide tomograms which are pixel maps of the velocity or attenuation anomalies in the rock. These anomalies are often due to fracture zones. Therefore, tomograms can be used to identify fracture zones and provide information about the structure within the fracture zones. This structural information can be used as the basis for simulating the degree of fracturing within the zones. Well tests can then be used to further refine the model. Because the fracture network is only partially connected, the resulting geometry of the flow paths may have fractal properties. We are studying the behavior of well tests under such geometry. Through understanding of this behavior, it may be possible to use inverse techniques to refine the a priori assignment of fractures and their conductances such that we obtain the best fit to a series of well test results simultaneously. The methodology described here is under development and currently being applied to several field sites. 4 refs., 14 figs.
Long, J.C.S.; Billaux, D.; Hestir, K.; Majer, E.L.; Peterson, J.; Karasaki, K.; Nihei, K.; Gentier, S.; Cox, L.
= heat, f = LO-mode, g = LO, h = LA-mode, i = negligible, j = remote heat sink 7/ 70 #12;Heat conductionFLUID MECHANICS AND HEAT TRANSFER OF ELECTRON FLOW IN SEMICONDUCTORS Mihir Sen Department · Shallow water analogy · Vorticity dynamics · Linear stability analysis · Numerical simulations of heat
Sen, Mihir
Fully Coupled Well Models for Fluid Injection and Production
Wells are the primary engineered component of geologic sequestration systems with deep subsurface reservoirs. Wells provide a conduit for injecting greenhouse gases and producing reservoirs fluids, such as brines, natural gas, and crude oil, depending on the target reservoir. Well trajectories, well pressures, and fluid flow rates are parameters over which well engineers and operators have control during the geologic sequestration process. Current drilling practices provided well engineers flexibility in designing well trajectories and controlling screened intervals. Injection pressures and fluids can be used to purposely fracture the reservoir formation or to purposely prevent fracturing. Numerical simulation of geologic sequestration processes involves the solution of multifluid transport equations within heterogeneous geologic media. These equations that mathematically describe the flow of fluid through the reservoir formation are nonlinear in form, requiring linearization techniques to resolve. In actual geologic settings fluid exchange between a well and reservoir is a function of local pressure gradients, fluid saturations, and formation characteristics. In numerical simulators fluid exchange between a well and reservoir can be specified using a spectrum of approaches that vary from totally ignoring the reservoir conditions to fully considering reservoir conditions and well processes. Well models are a numerical simulation approach that account for local conditions and gradients in the exchange of fluids between the well and reservoir. As with the mathematical equations that describe fluid flow in the reservoir, variation in fluid properties with temperature and pressure yield nonlinearities in the mathematical equations that describe fluid flow within the well. To numerically simulate the fluid exchange between a well and reservoir the two systems of nonlinear multifluid flow equations must be resolved. The spectrum of numerical approaches for resolving these equations varies from zero coupling to full coupling. In this paper we describe a fully coupled solution approach for well model that allows for a flexible well trajectory and screened interval within a structured hexahedral computational grid. In this scheme the nonlinear well equations have been fully integrated into the Jacobian matrix for the reservoir conservation equations, minimizing the matrix bandwidth.
White, Mark D.; Bacon, Diana H.; White, Signe K.; Zhang, Z. F.
Flows of Incompressible Newtonian and Generalized Newtonian Fluids over a Circular Cylinder
This thesis presents numerical solutions of the boundary value problems describing the isothermal and non-isothermal steady flows of incompressible Newtonian, power-law and Carreau fluids over a circular cylinder using the hpk-finite element process...g_i...max fluids (power-law and Carreau models) only shear thinning fluids are considered. Numerical studies demonstrate decoupled behavior of the temperature field from the rest of the deformation field. Shear thinning behavior and viscous dissipation for progressively increasing Reynolds numbers are simulated accurately without any difficulty....
Klein, Kayla
Effect of Fluid Flow on Inclusion Coarsening in Low-Alloy Steel Welds
Oxide inclusions form in welds because of deoxidation reactions in the weld pool. These inclusions control the weld microstructure development. Thermodynamic and kinetic calculation of oxidation reaction can describe inclusion characteristics such as number density, size, and composition. Experimental work has shown that fluid-flow velocity gradients in the weld pool can accelerate inclusion growth by collision and coalescence. Moreover, fluid flow in welds can transport inclusions to different temperature regions that may lead to repeated dissolution and growth of inclusions. These phenomena are being studied with the help of computational coupled heat transfer, fluid-flow, thermodynamic, and kinetic models. The results show that the inclusion formation in steel welds can be described as a function of the welding processes, process parameters, and steel composition.
Babu, S.S.; David, S.A.; DebRoy, T.; Hong, T.
Non-Steady wall-bounded flows of viscoelastic fluids under periodic forcing
The problem of oscillating flows inside pipes under periodic forcing of viscoelastic fluids is addressed here. Starting from the linear Oldroyd-B model, a generalized Darcy's law is obtained in frequency domain and an explicit expression for the dependence of the dynamic permeability on fluid parameters and forcing frequency is derived. Previous results in both viscoelastic and Newtonian fluids are here shown to be particular cases of our results. On the basis of our calculations, a possible explanation for the observed damping of local dynamic response as the forcing frequency increases is given. Good fitting with recent experimental studies of wave propagation in viscoelastic media is here exhibited. Sound wave propagation in viscoelastic media flowing inside straight pipes is investigated. In particular, we obtain the local dynamic response for weakly compressible flows.
Anier Hern�ndez-Garc�a; Antonio Fern�ndez-Barbero; Oscar Sotolongo-Costa
A splitting method for numerical simulation of free surface flows of incompressible fluids with surface tension
with surface tension Kirill D. Nikitin Maxim A. Olshanskii Kirill M. Terekhov Yuri V. Vassilevski§ Abstract to surface tension forces. The method splits one time step into a semi-Lagrangian treatment of the surface models a free surface flow of viscous incompressible fluid subject to surface tension forces. Further
Olshanskii, Maxim A.
Theoretical and Numerical Simulation of Non-Newtonian Fluid Flow in Propped Fractures
the original gel. The residual gel exhibits a higher yield stress, and is difficult to remove after fracture closure. But non-Newtonian fluid has complicated rheological equation and its flow behavior in porous media is difficult to be described and modeled...
Ouyang, Liangchen
The mathematical structure of multiphase thermal models of flow in porous media
The mathematical structure of multiphase thermal models of flow in porous media By Daniel E.A. van with the formulation and numerical solution of equations for modelling multicomponent, two-phase, thermal fluid flow typical flow behaviour that occurs during fluid injection into a reservoir. Keywords: porous media flow
Noninvasive Characterization Of A Flowing Multiphase Fluid Using Ultrasonic Interferometry
An apparatus for noninvasively monitoring the flow and/or the composition of a flowing liquid using ultrasound is described. The position of the resonance peaks for a fluid excited by a swept-frequency ultrasonic signal have been found to change frequency both in response to a change in composition and in response to a change in the flow velocity thereof. Additionally, the distance between successive resonance peaks does not change as a function of flow, but rather in response to a change in composition. Thus, a measurement of both parameters (resonance position and resonance spacing), once calibrated, permits the simultaneous determination of flow rate and composition using the apparatus and method of the present invention.
Sinha, Dipen N. (Los Alamos, NM)
Noninvasive characterization of a flowing multiphase fluid using ultrasonic interferometry
Sinha, Dipen N.
Device and method for measuring multi-phase fluid flow in a conduit using an elbow flow meter
A system for measuring fluid flow in a conduit. The system utilizes pressure transducers disposed generally in line upstream and downstream of the flow of fluid in a bend in the conduit. Data from the pressure transducers is transmitted to a microprocessor or computer. The pressure differential measured by the pressure transducers is then used to calculate the fluid flow rate in the conduit. Control signals may then be generated by the microprocessor or computer to control flow, total fluid dispersed, (in, for example, an irrigation system), area of dispersal or other desired effect based on the fluid flow in the conduit.
Ortiz, Marcos G. (Idaho Falls, ID); Boucher, Timothy J. (Helena, MT)
A system is described for measuring fluid flow in a conduit. The system utilizes pressure transducers disposed generally in line upstream and downstream of the flow of fluid in a bend in the conduit. Data from the pressure transducers is transmitted to a microprocessor or computer. The pressure differential measured by the pressure transducers is then used to calculate the fluid flow rate in the conduit. Control signals may then be generated by the microprocessor or computer to control flow, total fluid dispersed, (in, for example, an irrigation system), area of dispersal or other desired effect based on the fluid flow in the conduit. 2 figs.
Ortiz, M.G.; Boucher, T.J.
Fluid-elastic Instability of Helical Tubes Subjected to Single-Phase External Flow and Two-Phase Internal Flow
This study investigates the fluid-elastic instability characteristics of steam generator helical type tubes in operating nuclear power plants. The thermal-hydraulic conditions of both tube side and shell side flow fields are predicted by a general purpose computational fluid dynamics code employing the finite volume element modeling. To get the natural frequency, corresponding mode shape and participation factor, modal analyses are performed for helical type tubes with various conditions. Investigated are the effects of the helix angle, the number of supports and the status of the inner fluid on the modal, and fluid-elastic instability characteristics of the tubes, which are expressed in terms of the natural frequency, corresponding mode shape, and stability ratio. (authors)
Jong Chull Jo; Myung Jo Jhung; Woong Sik Kim; Hho Jung Kim [Korea Institute of Nuclear Safety, 19 Kusung-dong, Yusung-gu, Taejon 305-338 (Korea, Republic of)
Preserving the Volume of Fluid Using Multi-phase Flow Approach Roman Durikovic
complex behaviors. We often see rising bubbles or flow of muddy water, such flows involve sev- eral fluids volume when the fluid passes through a donor cell to an acceptor cell. The VOF method was improved
Durikovic, Roman
Standardization of Thermo-Fluid Modeling in Modelica.Fluid
Thermo-Fluid Systems, Modelica 2003 Conference, Link�ping,H. Tummescheit: The Modelica Fluid and Media Library forThermo-Fluid Pipe Networks, Modelica 2006 Conference, Vi-
Franke, Rudiger
FLUID DYNAMICAL AND MODELING ISSUES OF CHEMICAL FLOODING FOR ENHANCED OIL RECOVERY Prabir Daripa developed flows in enhanced oil recovery (EOR). In a recent exhaustive study [Transport in Porous Media, 93 fluid flows that occur in porous media during tertiary dis- placement process of chemical enhanced oil
Daripa, Prabir
Modelling anisotropic fluid spheres in general relativity
We argue that an arbitrary general relativistic anisotropic fluid sphere, (spherically symmetric but with transverse pressure not equal to radial pressure), can nevertheless be successfully modelled by suitable linear combinations of quite ordinary classical matter: an isotropic perfect fluid, a classical electromagnetic field, and a classical (minimally coupled) scalar field. While the most general decomposition is not unique, a preferred minimal decomposition can be constructed that is unique. We show how the classical energy conditions for the anisotropic fluid sphere can be related to energy conditions for the isotropic perfect fluid, electromagnetic field, and scalar field components of the model. Furthermore we show how this decomposition relates to the distribution of electric charge density and scalar charge density throughout the model that is used to mimic the anisotropic fluid sphere. Consequently, we can build physically reasonable matter models for almost any spherically symmetric spacetime.
Boonserm, Petarpa; Visser, Matt
Heat transfer to a fluid flowing in an annulus
. ii I ~ DIMENSIONS AND SYMBOLS o ~ ~ ~ . ~ ~ ~ ~ I II e INTRODUCTION AND THEORY ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ 3 IXI e APPARATUS AND PROCEDURES ~ ~ e ~ ~ ~ ~ ~ ~ ~ ~ 7 XV o RESULTS ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ e ~ ~ ~ ~ 17 V, DXSCUSSION OF RESULTS... of times 0 Prandtl nnnber~ e~& dimensionless initial temperature oi' surfaoe and fluids% D equivalent diameter& Di g~ L Q - volume flow rate~ L3/T V~ mass velooity, FT/L3 6 mass floe rate~ FT/L IMTRODUCTIOR AND THEORY This thesis comprises heat tz...
Logan, Earl
Internat. Congress on Science & Technology of Steelmaking, Charlotte, NC, May 9-12, AIST, Warrendale, PA, 2005, pp. 847-861. Modeling of Continuous-Casting Defects Related to Mold Fluid Flow
that is neither too cold nor too turbulent. In addition, the flow conditions should minimize exposure to air optimization. Fluid flow in the mold is controlled by many design parameters and operating conditions. Nozzle geometry is the most important, and includes the bore size, port angle, port opening size, nozzle wall
Reducing or stopping the uncontrolled flow of fluid such as oil from a well
The uncontrolled flow of fluid from an oil or gas well may be reduced or stopped by injecting a composition including 2-cyanoacrylate ester monomer into the fluid stream. Injection of the monomer results in a rapid, perhaps instantaneous, polymerization of the monomer within the flow stream of the fluid. This polymerization results in formation of a solid plug that reduces or stops the flow of additional fluid from the well.
Hermes, Robert E
Reduced order modeling of fluid/structure interaction.
This report describes work performed from October 2007 through September 2009 under the Sandia Laboratory Directed Research and Development project titled 'Reduced Order Modeling of Fluid/Structure Interaction.' This project addresses fundamental aspects of techniques for construction of predictive Reduced Order Models (ROMs). A ROM is defined as a model, derived from a sequence of high-fidelity simulations, that preserves the essential physics and predictive capability of the original simulations but at a much lower computational cost. Techniques are developed for construction of provably stable linear Galerkin projection ROMs for compressible fluid flow, including a method for enforcing boundary conditions that preserves numerical stability. A convergence proof and error estimates are given for this class of ROM, and the method is demonstrated on a series of model problems. A reduced order method, based on the method of quadratic components, for solving the von Karman nonlinear plate equations is developed and tested. This method is applied to the problem of nonlinear limit cycle oscillations encountered when the plate interacts with an adjacent supersonic flow. A stability-preserving method for coupling the linear fluid ROM with the structural dynamics model for the elastic plate is constructed and tested. Methods for constructing efficient ROMs for nonlinear fluid equations are developed and tested on a one-dimensional convection-diffusion-reaction equation. These methods are combined with a symmetrization approach to construct a ROM technique for application to the compressible Navier-Stokes equations.
Barone, Matthew Franklin; Kalashnikova, Irina; Segalman, Daniel Joseph; Brake, Matthew Robert
Extended fluid models: Pressure tensor effects and equilibria
We consider the use of �extended fluid models� as a viable alternative to computationally demanding kinetic simulations in order to manage the global large scale evolution of a collisionless plasma while accounting for the main effects that come into play when spatial micro-scales of the order of the ion inertial scale d{sub i} and of the thermal ion Larmor radius ?{sub i} are formed. We present an extended two-fluid model that retains finite Larmor radius (FLR) corrections to the ion pressure tensor while electron inertia terms and heat fluxes are neglected. Within this model we calculate analytic FLR plasma equilibria in the presence of a shear flow and elucidate the role of the magnetic field asymmetry. Using a Hybrid Vlasov code, we show that these analytic equilibria offer a significant improvement with respect to conventional magnetohydrodynamic shear-flow equilibria when initializing kinetic simulations.
Cerri, S. S. [Physics Department �E. Fermi,� University of Pisa and CNISM, Largo B. Pontecorvo 3, 56127 Pisa (Italy) [Physics Department �E. Fermi,� University of Pisa and CNISM, Largo B. Pontecorvo 3, 56127 Pisa (Italy); Max-Planck-Institut f�r Plasmaphysik, EURATOM association, Boltzmannstr. 2, D-85748 Garching (Germany); Henri, P. [Physics Department �E. Fermi,� University of Pisa and CNISM, Largo B. Pontecorvo 3, 56127 Pisa (Italy) [Physics Department �E. Fermi,� University of Pisa and CNISM, Largo B. Pontecorvo 3, 56127 Pisa (Italy); Universit� de Nice Sophia Antipolis, CNRS, Observatoire de la C�te d'Azur, BP 4229 06304, Nice Cedex 4 (France); Califano, F.; Pegoraro, F. [Physics Department �E. Fermi,� University of Pisa and CNISM, Largo B. Pontecorvo 3, 56127 Pisa (Italy)] [Physics Department �E. Fermi,� University of Pisa and CNISM, Largo B. Pontecorvo 3, 56127 Pisa (Italy); Del Sarto, D. [Institut Jean Lamour, UMR 7198 CNRS � Universit� de Lorraine, BP 239 F-54506 Vandoeuvre les Nancy (France)] [Institut Jean Lamour, UMR 7198 CNRS � Universit� de Lorraine, BP 239 F-54506 Vandoeuvre les Nancy (France); Faganello, M. [International Institute for Fusion Science/PIIM, UMR 7345 CNRS Aix-Marseille University, Marseille (France)] [International Institute for Fusion Science/PIIM, UMR 7345 CNRS Aix-Marseille University, Marseille (France)
Influence of formation clays on the flow of aqueous fluids
Most sandstone formations contain clays that can have a significant effect on the flow of aqueous fluids. The clays most frequently detected are smectite, mixed layer, illite, kaolinite, and chlorite. All of these clays are capable of migrating and causing permeability damage when they are contacted by waters foreign to the formation. Normally, these waters alter ionic environments around the clays, which causes the clays to be dislodged from their original positions. Thus, any time clay is present in the rock, it can be assumed that permeability damage can occur. The degree of damage depends upon the concentration and types of clays present, their relative position in the rock, the severity of the ionic environmental change; and fluid velocity. Permeability damage has been minimized in oil and gas wells through the use of potassium and ammonium ions. 15 references.
Hower, W.F.
Production of Natural Gas and Fluid Flow in Tight Sand Reservoirs
This document reports progress of this research effort in identifying relationships and defining dependencies between macroscopic reservoir parameters strongly affected by microscopic flow dynamics and production well performance in tight gas sand reservoirs. These dependencies are investigated by identifying the main transport mechanisms at the pore scale that should affect fluids flow at the reservoir scale. A critical review of commercial reservoir simulators, used to predict tight sand gas reservoir, revealed that many are poor when used to model fluid flow through tight reservoirs. Conventional simulators ignore altogether or model incorrectly certain phenomena such as, Knudsen diffusion, electro-kinetic effects, ordinary diffusion mechanisms and water vaporization. We studied the effect of Knudsen's number in Klinkenberg's equation and evaluated the effect of different flow regimes on Klinkenberg's parameter b. We developed a model capable of explaining the pressure dependence of this parameter that has been experimentally observed, but not explained in the conventional formalisms. We demonstrated the relevance of this, so far ignored effect, in tight sands reservoir modeling. A 2-D numerical simulator based on equations that capture the above mentioned phenomena was developed. Dynamic implications of new equations are comprehensively discussed in our work and their relative contribution to the flow rate is evaluated. We performed several simulation sensitivity studies that evidenced that, in general terms, our formalism should be implemented in order to get more reliable tight sands gas reservoirs' predictions.
Maria Cecilia Bravo
Nonlinear dynamics of magnetohydrodynamic flows of heavy fluid over an arbitrary surface
equations system for heavy fluid over an arbitrary surface in shallow water approximation is studied to the study of nonlinear flows of heavy fluid described by the shallow water magnetohydrodynamic equations1 Nonlinear dynamics of magnetohydrodynamic flows of heavy fluid over an arbitrary surface
The simulation of free surface flows with Computational Fluid Dynamics B. Godderidge1
1 The simulation of free surface flows with Computational Fluid Dynamics B. Godderidge1 A of these applications make their simulation with computational fluid dynamics particularly challenging. The successful Computational fluid dynamics is a powerful and versatile tool for the analysis of flow problems encountered
Abrupt contraction flow of magnetorheological fluids , M.T. Lpez-Lpez1,2
engineering interest, the MR fluids are very attractive from a purely scientific point of view. The coupling1 Abrupt contraction flow of magnetorheological fluids P. Kuzhir1 , M.T. López-López1,2 and G Granada, 18071 Granada, Spain Abstract Contraction and expansion flows of magnetorheological fluids occur
Derivation of Newton's Law of Gravitation Based on a Fluid Mechanical Singularity Model of Particles
We speculate that the universe may be filled with a kind of fluid which may be called aether or tao. Thus, Newton's law of gravitation is derived by methods of hydrodynamics based on a sink flow model of particles.
Xiao-Song Wang
UZ Flow Models and Submodels
The purpose of this report is to document the unsaturated zone (UZ) flow models and submodels, as well as the flow fields that have been generated using the UZ flow model(s) of Yucca Mountain, Nevada. In this report, the term ''UZ model'' refers to the UZ flow model and the several submodels, which include tracer transport, temperature or ambient geothermal, pneumatic or gas flow, and geochemistry (chloride, calcite, and strontium) submodels. The term UZ flow model refers to the three-dimensional models used for calibration and simulation of UZ flow fields. This work was planned in the ''Technical Work Plan (TWP) for: Unsaturated Zone Flow Analysis and Model Report Integration'' (BSC 2004 [DIRS 169654], Section 1.2.7). The table of included Features, Events, and Processes (FEPs), Table 6.2-11, is different from the list of included FEPs assigned to this report in the ''Technical Work Plan for: Unsaturated Zone Flow Analysis and Model Report Integration'' (BSC 2004 [DIRS 169654], Table 2.1.5-1), as discussed in Section 6.2.6. The UZ model has revised, updated, and enhanced the previous UZ model (BSC 2001 [DIRS 158726]) by incorporating the repository design with new grids, recalibration of property sets, and more comprehensive validation effort. The flow fields describe fracture-fracture, matrix-matrix, and fracture-matrix liquid flow rates, and their spatial distributions as well as moisture conditions in the UZ system. These three-dimensional UZ flow fields are used directly by Total System Performance Assessment (TSPA). The model and submodels evaluate important hydrogeologic processes in the UZ as well as geochemistry and geothermal conditions. These provide the necessary framework to test hypotheses of flow and transport at different scales, and predict flow and transport behavior under a variety of climatic conditions. In addition, the limitations of the UZ model are discussed in Section 8.11.
Y. Wu
Hydrostatic bearings for a turbine fluid flow metering device
A rotor assembly fluid metering device has been improved by development of a hydrostatic bearing fluid system which provides bearing fluid at a common pressure to rotor assembly bearing surfaces. The bearing fluid distribution system produces a uniform film of fluid between bearing surfaces and allows rapid replacement of bearing fluid between bearing surfaces, thereby minimizing bearing wear and corrosion. 3 figs.
Fincke, J.R.
A rotor assembly fluid metering device has been improved by development of a hydrostatic bearing fluid system which provides bearing fluid at a common pressure to rotor assembly bearing surfaces. The bearing fluid distribution system produces a uniform film of fluid between bearing surfaces and allows rapid replacement of bearing fluid between bearing surfaces, thereby minimizing bearing wear and corrosion.
Fincke, James R. (Rigby, ID)
Microscale Fluid Flow Induced by Thermoviscous Expansion Along a Traveling Wave Franz M. Weinert,1
are negli- gible if the velocities are small with respect to the speed of sound, fluid flow is essentially confinement of a liquid changes its flow behavior markedly since the importance of surface forces relative a novel mechanism to generate net flow in a thin fluid chamber, i.e., a viscous liquid confined between
Kersting, Roland
Compressible fluid model for hydrodynamic lubrication cavitation
Compressible fluid model for hydrodynamic lubrication cavitation G. Bayada L. Chupin I.C.J. email@example.com Keywords: cavitation, compressible Reynolds equation Date: april 2013 Summary In this paper, it is shown how vaporous cavitation in lubricant films can be modelled in a physically justified manner through
Sart, Remi
TOUGH Simulations of the Updegraff's Set of Fluid and Heat Flow Problems
The TOUGH code [Pruess, 1987] for two-phase flow of water, air, and heat in penneable media has been exercised on a suite of test problems originally selected and simulated by C. D. Updegraff [1989]. These include five 'verification' problems for which analytical or numerical solutions are available, and three 'validation' problems that model laboratory fluid and heat flow experiments. All problems could be run without any code modifications (*). Good and efficient numerical performance, as well as accurate results were obtained throughout. Additional code verification and validation problems from the literature are briefly summarized, and suggestions are given for proper applications of TOUGH and related codes.
Moridis, G.J.; Pruess (editor), K.
A Finite-Difference Numerical Method for Onsager's Pancake Approximation for Fluid Flow in a Gas Centrifuge
Gas centrifuges exhibit very complex flows. Within the centrifuge there is a rarefied region, a transition region, and a region with an extreme density gradient. The flow moves at hypersonic speeds and shock waves are present. However, the flow is subsonic in the axisymmetric plane. The analysis may be simplified by treating the flow as a perturbation of wheel flow. Wheel flow implies that the fluid is moving as a solid body. With the very large pressure gradient, the majority of the fluid is located very close to the rotor wall and moves at an azimuthal velocity proportional to its distance from the rotor wall; there is no slipping in the azimuthal plane. The fluid can be modeled as incompressible and subsonic in the axisymmetric plane. By treating the centrifuge as long, end effects can be appropriately modeled without performing a detailed boundary layer analysis. Onsager's pancake approximation is used to construct a simulation to model fluid flow in a gas centrifuge. The governing 6th order partial differential equation is broken down into an equivalent coupled system of three equations and then solved numerically. In addition to a discussion on the baseline solution, known problems and future work possibilities are presented.
de Stadler, M; Chand, K
Prolonged effect of fluid flow stress on the proliferative activity of mesothelial cells after abrupt discontinuation of fluid streaming
Highlights: Black-Right-Pointing-Pointer Late-onset peritoneal fibrosis leading to EPS remains to be elucidated. Black-Right-Pointing-Pointer Fluid streaming is a potent factor for peritoneal fibrosis in PD. Black-Right-Pointing-Pointer We focused on the prolonged effect of fluid streaming on mesothelial cell kinetics. Black-Right-Pointing-Pointer A history of fluid streaming exposure promoted mesothelial proliferative activity. Black-Right-Pointing-Pointer We have thus identified a potent new factor for late-onset peritoneal fibrosis. -- Abstract: Encapsulating peritoneal sclerosis (EPS) often develops after transfer to hemodialysis and transplantation. Both termination of peritoneal dialysis (PD) and transplantation-related factors are risks implicated in post-PD development of EPS, but the precise mechanism of this late-onset peritoneal fibrosis remains to be elucidated. We previously demonstrated that fluid flow stress induced mesothelial proliferation and epithelial-mesenchymal transition via mitogen-activated protein kinase (MAPK) signaling. Therefore, we speculated that the prolonged bioactive effect of fluid flow stress may affect mesothelial cell kinetics after cessation of fluid streaming. To investigate how long mesothelial cells stay under the bioactive effect brought on by fluid flow stress after removal of the stress, we initially cultured mesothelial cells under fluid flow stress and then cultured the cells under static conditions. Mesothelial cells exposed to fluid flow stress for a certain time showed significantly high proliferative activity compared with static conditions after stoppage of fluid streaming. The expression levels of protein phosphatase 2A, which dephosphorylates MAPK, in mesothelial cells changed with time and showed a biphasic pattern that was dependent on the duration of exposure to fluid flow stress. There were no differences in the fluid flow stress-related bioactive effects on mesothelial cells once a certain time had passed. The present findings show that fluid flow stress exerts a prolonged bioactive effect on mesothelial cells after termination of fluid streaming. These findings support the hypothesis that a history of PD for a certain period could serve as a trigger of EPS after stoppage of PD.
Aoki, Shigehisa, E-mail: email@example.com [Department of Pathology and Microbiology, Faculty of Medicine, Saga University, Saga (Japan)] [Department of Pathology and Microbiology, Faculty of Medicine, Saga University, Saga (Japan); Ikeda, Satoshi [Department of Pathology and Microbiology, Faculty of Medicine, Saga University, Saga (Japan)] [Department of Pathology and Microbiology, Faculty of Medicine, Saga University, Saga (Japan); Takezawa, Toshiaki [Transgenic Animal Research Center, National Institute of Agrobiological Sciences, Ibaraki (Japan)] [Transgenic Animal Research Center, National Institute of Agrobiological Sciences, Ibaraki (Japan); Kishi, Tomoya [Department of Internal Medicine, Saga University, Saga (Japan)] [Department of Internal Medicine, Saga University, Saga (Japan); Makino, Junichi [Makino Clinic, Saga (Japan)] [Makino Clinic, Saga (Japan); Uchihashi, Kazuyoshi; Matsunobu, Aki [Department of Pathology and Microbiology, Faculty of Medicine, Saga University, Saga (Japan)] [Department of Pathology and Microbiology, Faculty of Medicine, Saga University, Saga (Japan); Noguchi, Mitsuru [Department of Urology, Faculty of Medicine, Saga University, Saga (Japan)] [Department of Urology, Faculty of Medicine, Saga University, Saga (Japan); Sugihara, Hajime [Department of Physical Therapy, International University of Health and Welfare, Fukuoka (Japan)] [Department of Physical Therapy, International University of Health and Welfare, Fukuoka (Japan); Toda, Shuji [Department of Pathology and Microbiology, Faculty of Medicine, Saga University, Saga (Japan)] [Department of Pathology and Microbiology, Faculty of Medicine, Saga University, Saga (Japan)
A rotor assembly fluid metering device has been improved by development of a hydrostatic bearing fluid system which provides bearing fluid at a common pressure to rotor assembly bearing surfaces. The bearing fluid distribution system produces a uniform film of fluid distribution system produces a uniform film of fluid between bearing surfaces and allows rapid replacement of bearing fluid between bearing surfaces, thereby minimizing bearing wear and corrosion.
Wave-induced fluid flow in random porous media: Attenuation and ...
wave attenuation and dispersion due to wave-induced fluid flow in 3-D randomly inhomogeneous .... tenuation is controlled by the integrand, that is, by the prod-.
FRACSTIMI: A Fully Coupled Fluid FlowHeat Transport and Geomechanical DeformationFracture Generation Simulator aka FALCON: Fracturing and Liquid CONservation Robert K....
Stress and Fluid-Flow Interaction for the Coso Geothermal Field...
California is reliant on the knowledge of fluid flow directions associated with fracture networks. We use finite element analysis to establish the 3D state of stress within...
Scaling up and modeling for transport and flow
& modélisation des écoulements de fluides en milieux poreux DUBROVNIK, CROATIA 13-16 OCTOBER 2008 BOOK for Transport and Flow in Porous Media Dubrovnik, Croatia, 13-16 October 2008 Book of abstracts #12;Contents and Modeling for Transport and Flow in Porous Media, held at Dubrovnik, Croatia, 1316 October 2008
Rogina, Mladen
System and method for bidirectional flow and controlling fluid flow in a conduit
A system for measuring bidirectional flow, including backflow, of fluid in a conduit. The system utilizes a structural mechanism to create a pressure differential in the conduit. Pressure sensors are positioned upstream from the mechanism, at the mechanism, and downstream from the mechanism. Data from the pressure sensors are transmitted to a microprocessor or computer, and pressure differential detected between the pressure sensors is then used to calculate the backflow. Control signals may then be generated by the microprocessor or computer to shut off valves located in the conduit, upon the occurrence of backflow, or to control flow, total material dispersed, etc. in the conduit.
Ortiz, Marcos German (Idaho Falls, ID)
A system for measuring bidirectional flow, including backflow, of fluid in a conduit is disclosed. The system utilizes a structural mechanism to create a pressure differential in the conduit. Pressure sensors are positioned upstream from the mechanism, at the mechanism, and downstream from the mechanism. Data from the pressure sensors are transmitted to a microprocessor or computer, and pressure differential detected between the pressure sensors is then used to calculate the backflow. Control signals may then be generated by the microprocessor or computer to shut off valves located in the conduit, upon the occurrence of backflow, or to control flow, total material dispersed, etc. in the conduit. 3 figs.
Ortiz, M.G.
On fluid flow in a heterogeneous medium under nonisothermal conditions
An asymptotic technique, valid in the presence of smoothly-varying heterogeneity, provides explicit expressions for the velocity of a propagating pressure and temperature disturbance. The governing equations contain nonlinear terms due to the presence of temperature-dependent coefficients and due to the advection of fluids with differing temperatures. Two cases give well-defined expressions in terms of the parameters of the porous medium: the uncoupled propagation of a pressure disturbance and the propagation of a fully coupled temperature and pressure disturbance. The velocity of the coupled disturbance or front, depends upon the medium parameters and upon the change in temperature and pressure across the front. For uncoupled flow, the semi-analytic expression for the front velocity reduces to that associated with a linear diffusion equation. A comparison of the asymptotic travel time estimates with calculations from a numerical simulator indicates reasonably good agreement for both uncoupled and coupled disturbances.
D.W., Vasco
The objective of Task 2 is to develop a numerical method for the efficient and accurate analysis of distributed thermal perturbation sensing (DTPS) data for (1) imaging flow profiles and (2) in situ determination of thermal conductivities and heat fluxes. Numerical forward and inverse modeling is employed to: (1) Examine heat and fluid flow processes near a geothermal well under heating and cooling conditions; (2) Demonstrate ability to interpret DTPS thermal profiles with acceptable estimation uncertainty using inverse modeling of synthetic temperature data; and (3) Develop template model and analysis procedure for the inversion of temperature data collected during a thermal perturbation test using fiber-optic distributed temperature sensors. This status report summarizes initial model developments and analyses.
Freifeld, B.; Finsterle, S.
DOE Fundamentals Handbook: Thermodynamics, Heat Transfer, and Fluid Flow, Volume 2
The Thermodynamics, Heat Transfer, and Fluid Flow Fundamentals Handbook was developed to assist nuclear facility operating contractors provide operators, maintenance personnel, and the technical staff with the necessary fundamentals training to ensure a basic understanding of the thermal sciences. The handbook includes information on thermodynamics and the properties of fluids; the three modes of heat transfer -- conduction, convection, and radiation; and fluid flow, and the energy relationships in fluid systems. This information will provide personnel with a foundation for understanding the basic operation of various types of DOE nuclear facility fluid systems.
Not Available
DOE Fundamentals Handbook: Thermodynamics, Heat Transfer, and Fluid Flow, Volume 1
DOE Fundamentals Handbook: Thermodynamics, Heat Transfer, and Fluid Flow, Volume 3
Relation Between Flow Enhancement Factor and Structure for Core-Softened Fluids Inside Nanotubes
Relation Between Flow Enhancement Factor and Structure for Core-Softened Fluids Inside Nanotubes The relationship between enhancement flow and structure of core-softened fluids confined inside nanotubes has been was employed to create a pressure gradient between two reservoirs connected by a nanotube. We show how
Barbosa, Marcia C. B.
Global weak solutions to magnetic fluid flows with nonlinear Maxwell-Cattaneo heat transfer law
Global weak solutions to magnetic fluid flows with nonlinear Maxwell-Cattaneo heat transfer law F transfer in a magnetic fluid flow under the action of an applied magnetic field. Instead of the usual heat-Cattaneo law, heat transfer, magnetic field, magnetization AMS subject classifications: 76N10, 35Q35. 1
NUMERICAL STUDY OF FLUID FLOW AND HEAT TRANSFER OVER A SERIES OF IN-LINE NONCIRCULAR TUBES CONFINED, Texas A&M University, College Station, Texas, USA Two-dimensional steady developing fluid flow and heat-volume technique. Grid independence study was carried out by running the developed code for several different grid
Bahaidarah, Haitham M.
The effects of topology upon fluid-flow and heat-transfer within cellular copper structures
and packed beds, but also a function of orientation (open area ratio). The overall heat transfer dependsThe effects of topology upon fluid-flow and heat-transfer within cellular copper structures J. Tian February 2004 Available online 20 March 2004 Abstract The fluid-flow and heat-transfer features of cellular
Wadley, Haydn
Pulsatile flow of a chemically-reacting non-linear fluid
of such fluids could change because of the chemical reactions and the flow. Here, I investigate the pulsatile flow of a chemically-reacting fluid whose viscosity depends on the concentration of a species (constituent) that is governed by a convection...
Bridges, Ronald Craig, II
Computational fluid dynamic modeling of fluidized-bed polymerization reactors
Polyethylene is one of the most widely used plastics, and over 60 million tons are produced worldwide every year. Polyethylene is obtained by the catalytic polymerization of ethylene in gas and liquid phase reactors. The gas phase processes are more advantageous, and use fluidized-bed reactors for production of polyethylene. Since they operate so close to the melting point of the polymer, agglomeration is an operational concern in all slurry and gas polymerization processes. Electrostatics and hot spot formation are the main factors that contribute to agglomeration in gas-phase processes. Electrostatic charges in gas phase polymerization fluidized bed reactors are known to influence the bed hydrodynamics, particle elutriation, bubble size, bubble shape etc. Accumulation of electrostatic charges in the fluidized-bed can lead to operational issues. In this work a first-principles electrostatic model is developed and coupled with a multi-fluid computational fluid dynamic (CFD) model to understand the effect of electrostatics on the dynamics of a fluidized-bed. The multi-fluid CFD model for gas-particle flow is based on the kinetic theory of granular flows closures. The electrostatic model is developed based on a fixed, size-dependent charge for each type of particle (catalyst, polymer, polymer fines) phase. The combined CFD model is first verified using simple test cases, validated with experiments and applied to a pilot-scale polymerization fluidized-bed reactor. The CFD model reproduced qualitative trends in particle segregation and entrainment due to electrostatic charges observed in experiments. For the scale up of fluidized bed reactor, filtered models are developed and implemented on pilot scale reactor.
Rokkam, Ram [Ames Laboratory
Subcritical finite-amplitude solutions in plane Couette flow of visco-elastic fluids
Plane Couette flow of visco-elastic fluids is shown to exhibit a purely elastic subcritical instability in spite of being linearly stable. The mechanism of this instability is proposed and the nonlinear stability analysis of plane Couette flow of the Upper-Convected Maxwell fluid is presented. It is found that above the critical Weissenberg number, a small finite-size perturbation is sufficient to create a secondary flow, and the threshold value for the amplitude of the perturbation decreases as the Weissenberg number increases. The results suggest a scenario for weakly turbulent visco-elastic flow which is similar to the one for Newtonian fluids as a function of Reynolds number.
Alexander N. Morozov; Wim van Saarloos
Magnetic fluid flow phenomena in DC and rotating magnetic fields
An investigation of magnetic fluid experiments and analysis is presented in three parts: a study of magnetic field induced torques in magnetorheological fluids, a characterization and quantitative measurement of properties ...
Rhodes, Scott E. (Scott Edward), 1981-
Time-lapse seismic monitoring of subsurface fluid flow
Time-lapse seismic monitoring repeats 3D seismic imaging over a reservoir to map fluid movements in a reservoir. During hydrocarbon production, the fluid saturation, pressure, and temperature of a reservoir change, thereby altering the acoustic...
Yuh, Sung H.
A simple segregated flow model for a WAG process
integration, a volumetric balance of the injectants and the initial reservoir fluids is obtained. The model was developed with several simplifying assumptions including immiscible water and gas phases, incompressible fluid f'low, no trapped oil volumes... with the process are the relatively higher sweep efficiencies of water floods and the low residual oil saturations of miscible gas injection. The mechanism oP water flooding is generally well understood. Many Pields have been and still are being waterflooded...
Hopkins, Christopher Wright
Multiscale modeling in granular flow
Granular materials are common in everyday experience, but have long-resisted a complete theoretical description. Here, we consider the regime of slow, dense granular flow, for which there is no general model, representing ...
Rycroft, Christopher Harley
Multiphase Fluid Flow in Deformable Variable-Aperture Fractures - Final Report
Fractures provide flow paths that can potentially lead to fast migration of fluids or contaminants. A number of energy-�?related applications involve fluid injections that significantly perturb both the pressures and chemical composition of subsurface fluids. These perturbations can cause both mechanical deformation and chemical alteration of host rocks with potential for significant changes in permeability. In fractured rock subjected to coupled chemical and mechanical stresses, it can be difficult to predict the sign of permeability changes, let alone the magnitude. This project integrated experimental and computational studies to improve mechanistic understanding of these coupled processes and develop and test predictive models and monitoring techniques. The project involved three major components: (1) study of two-�?phase flow processes involving mass transfer between phases and dissolution of minerals along fracture surfaces (Detwiler et al., 2009; Detwiler, 2010); (2) study of fracture dissolution in fractures subjected to normal stresses using experimental techniques (Ameli, et al., 2013; Elkhoury et al., 2013; Elkhoury et al., 2014) and newly developed computational models (Ameli, et al., 2014); (3) evaluation of electrical resistivity tomography (ERT) as a method to detect and quantify gas leakage through a fractured caprock (Breen et al., 2012; Lochbuhler et al., 2014). The project provided support for one PhD student (Dr. Pasha Ameli; 2009-�?2013) and partially supported a post-�?doctoral scholar (Dr. Jean Elkhoury; 2010-�?2013). In addition, the project provided supplemental funding to support collaboration with Dr. Charles Carrigan at Lawrence Livermore National Laboratory in connection with (3) and supported one MS student (Stephen Breen; 2011-�?2013). Major results from each component of the project include the following: (1) Mineral dissolution in fractures occupied by two fluid phases (e.g., oil-�?water or water-�?CO{sub 2}) causes changes in local capillary forces and redistribution of fluids. These coupled processes enhance channel formation and the potential for development of fast flow paths through fractures. (2) Dissolution in fractures subjected to normal stress can result in behaviors ranging from development of dissolution channels and rapid permeability increases to fracture healing and significant permeability decreases. The timescales associated with advective transport of dissolved ions in the fracture, mineral dissolution rates, and diffusion within the adjacent porous matrix dictate the sign and magnitude of the resulting permeability changes. Furthermore, a high-�? resolution mechanistic model that couples elastic deformation of contacts and aperture-�?dependent dissolution rates predicts the range of observed behaviors reasonably well. (3) ERT has potential as a tool for monitoring gas leakage in deep formations. Using probabilistic inversion methods further enhances the results by providing uncertainty estimates of inverted parameters.
Detwiler, Russell
2.13 HEAT TRANSFER & FLUID FLOW IN MICROCHANNELS 2.13.7-1 Molecular dynamics methods in
2.13 HEAT TRANSFER & FLUID FLOW IN MICROCHANNELS 2.13.7-1 2.13.7 Molecular dynamics methods in microscale heat transfer Shigeo Maruyama A. Introduction In normal heat transfer and fluid flow calculations of molecules. This situation is approached in microscale heat transfer and fluid flow. Molecular level
Maruyama, Shigeo
Method and apparatus for measuring the mass flow rate of a fluid
A non invasive method and apparatus is provided to measure the mass flow rate of a multi-phase fluid. An accelerometer is attached to a pipe carrying a multi-phase fluid. Flow related measurements in pipes are sensitive to random velocity fluctuations whose magnitude is proportional to the mean mass flow rate. An analysis of the signal produced by the accelerometer shows a relationship between the mass flow of a fluid and the noise component of the signal of an accelerometer. The noise signal, as defined by the standard deviation of the accelerometer signal allows the method and apparatus of the present invention to non-intrusively measure the mass flow rate of a multi-phase fluid.
Evans, Robert P. (Idaho Falls, ID); Wilkins, S. Curtis (Idaho Falls, ID); Goodrich, Lorenzo D. (Shelley, ID); Blotter, Jonathan D. (Pocatello, ID)
A nonlocal model for fluid-structure interaction with applications in hydraulic fracturing
Modeling important engineering problems related to flow-induced damage (in the context of hydraulic fracturing among others) depends critically on characterizing the interaction of porous media and interstitial fluid flow. This work presents a new formulation for incorporating the effects of pore pressure in a nonlocal representation of solid mechanics. The result is a framework for modeling fluid-structure interaction problems with the discontinuity capturing advantages of an integral based formulation. A number of numerical examples are used to show that the proposed formulation can be applied to measure the effect of leak-off during hydraulic fracturing as well as modeling consolidation of fluid saturated rock and surface subsidence caused by fluid extraction from a geologic reservoir. The formulation incorporates the effect of pore pressure in the constitutive description of the porous material in a way that is appropriate for nonlinear materials, easily implemented in existing codes, straightforward in i...
Turner, Daniel Z
Multiscale Simulation Framework for Coupled Fluid Flow and Mechanical Deformation
A multiscale linear-solver framework for the pressure equation associated with flow in highly heterogeneous porous formations was developed. The multiscale based approach is cast in a general algebraic form, which facilitates integration of the new scalable linear solver in existing flow simulators. The Algebraic Multiscale Solver (AMS) is employed as a preconditioner within a multi-stage strategy. The formulations investigated include the standard MultiScale Finite-Element (MSFE) andMultiScale Finite-Volume (MSFV) methods. The local-stage solvers include incomplete factorization and the so-called Correction Functions (CF) associated with the MSFV approach. Extensive testing of AMS, as an iterative linear solver, indicate excellent convergence rates and computational scalability. AMS compares favorably with advanced Algebraic MultiGrid (AMG) solvers for highly detailed three-dimensional heterogeneous models. Moreover, AMS is expected to be especially beneficial in solving time-dependent problems of coupled multiphase flow and transport in large-scale subsurface formations.
Tchelepi, Hamdi
A mechanistic model for computing fluid temperature profiles in gas-lift wells
In a continuous-flow gas-lift operation, gas is injected down the annulus into the tubing near the top of perforations. The intrinsic idea is to aerate the liquid column, thus providing the necessary stimulus for fluid flow. Because the volumetric gas rate is dependent upon both the pressure and temperature at the depth of injection, accurate knowledge of these entities cannot be overemphasized for an efficient lift. In particular, the behavior of the nitrogen gas charged in the dome is critically dependent upon the temperature prediction for the optimal performance of the bellows-charged gas-lift valves. Current practice entails use of a linear temperature profile for the annular fluid while applying empirical correlations for the tubing fluids. Improved temperature predictions are now possible for fluids in both conduits by modeling the heat and fluid flow problem at hand from first principles. In this work, they present a mechanistic model for the flowing temperature of the annular gas and the gas/liquid two-phase mixture in the tubing as a function of both well depth and production time, regardless of the well deviation angle. The model is based on energy balance between the formation and fluids flowing through each conduit. While flowing down the annulus, the cold gas injected at the wellhead continues to gain heat. The heat-transfer rate for the annular gas depends on the relative temperatures of the formation and the tubing fluid. They assume unsteady-state heat transfer in the formation and steady-state heat transfer in the tubular for a continuous-flow gas-lift operation.
Hasan, A.R. [Univ. of North Dakota, Grand Forks, ND (United States); Kabir, C.S. [Chevron Overseas Petroleum Technology Co. (Kuwait)
Fluid flow through very low permeability materials: A concern in the geological isolation of waste
The geological isolation of waste usually involves the selection of sites where very low permeability materials exist, but there are few earth materials that are truly impermeable. Regulatory concerns for the containment of radioactive material extend for geologic periods of time (i.e., 10,000 years or more), and it becomes nearly impossible to ``assure`` the behavior of the site for such long periods of time. Experience at the Waste Isolation Pilot Plant (WIPP) shows that very slow movements of fluid can take place through materials that may, in fact, have no intrinsic permeability in their undisturbed condition. Conventional hydrologic models may not be appropriate to describe flow, may provide modeling results that could be in significant variance with reality, and may not be easy to defend during the compliance process. Additionally, the very small volumes of fluid and very slow flow rates involved are difficult to observe, measure, and quantify. The WIPP disposal horizon is excavated 655 m below the surface in bedded salt of Permian age. Salt has some unique properties, but similar hydrologic problems can be expected in site investigations were other relatively impermeable beds occur, and especially in deep sites where significant overburden and confining pressures may be encountered. Innovative techniques developed during the investigations at the WIPP may find utility when investigating other disposal sites. Ongoing work at the WIPP is expected to continue to advance understanding of flow through very low permeability materials. The study of flow under these conditions will become increasingly important as additional waste disposal sites are designed that require assurance of their safety for geological periods of time.
Deal, D.E.
6. Fluid mechanics: fluid statics; fluid dynamics
1/96 6. Fluid mechanics: fluid statics; fluid dynamics (internal flows, external flows) Ron and Flow Engineering | 20500 Turku | Finland 2/96 6.1 Fluid statics �?bo Akademi University | Thermal and Flow Engineering | 20500 Turku | Finland #12;3/96 Fluid statics, static pressure /1 Two types
Zevenhoven, Ron
Fluid Flow and Infiltration in Structured Fibrous Porous Media
Present the results of an extensive computational investigation of flow through structured fibrous media.
Papathanasiou, Thanasis D.
The stability of viscoelastic fluids in complex flows : the role of shear and extensional rheology
Understanding the flow of polymeric fluids is important for optimizing commercial processes such as injection molding and fiber spinning. The combination of streamwise curvature and elastic normal stresses can lead to the ...
Rothstein, Jonathan P. (Jonathan Philip), 1974-
FRACTURE AND FLUID FLOW ANALYSIS-EAST FLANK OF THE COSO GEOTHERMAL FIELD Jump to: navigation, search OpenEI Reference LibraryAdd to library Conference Proceedings: IN SITU STRESS,...
FRACTURE, AND FLUID FLOW ANALYSIS IN WELL 38C-9:AN ENHANCED GEOTHERMAL SYSTEM IN THE COSO GEOTHERMAL FIELD Jump to: navigation, search OpenEI Reference LibraryAdd to library...
In situ stress, fracture, and fluid flow analysis in Well 38C...
situ stress, fracture, and fluid flow analysis in Well 38C-9: an enhanced geothermal system in the Coso geothermal field Jump to: navigation, search OpenEI Reference LibraryAdd to...
Permeability of illite-bearing shale: 2. Influence of fluid chemistry on flow and functionally
of the Wilcox formation has been investigated using distilled water and 1 M solutions of NaCl, KCl, and CaCl2 and permeabilities depend on fluid composition. Permeabilities to flow of 1 M CaCl2 are 35 times greater than values is greater for transport of 1 M CaCl2 than that for transport of the other pore fluids. Assuming that fluid
Herbert, Bruce
OnLine IPA Gradient Estimators in Stochastic Continuous Fluid Models
OnLine IPA Gradient Estimators in Stochastic Continuous Fluid Models Yorai Wardi # School Perturbation Analysis (IPA) to lossrelated and workload related metrics in a class of Stochastic Flow Models parameters of interest, such as bu#er size, service rate and inflow rate. The IPA estimators derived
American Institute of Aeronautics and Astronautics Three-dimensional Plasma and Fluid Flow Structures inside a
devices. Mechanical micropumps drive the working fluid through a membrane or diaphragm, while non-mechanical1 American Institute of Aeronautics and Astronautics Three-dimensional Plasma and Fluid Flow Plasma Dynamics Laboratory and Test Facility Mechanical and Aerospace Engineering Department University
Roy, Subrata
Cartesian Cut Cell Two-Fluid Solver for Hydraulic Flow Problems
Cartesian Cut Cell Two-Fluid Solver for Hydraulic Flow Problems L. Qian1 ; D. M. Causon2 ; D. M. Ingram3 ; and C. G. Mingham4 Abstract: A two-fluid solver which can be applied to a variety of hydraulic with a sloping beach is also calculated to demonstrate the applicability of the method to real hydraulic problems
Ingram, David
applications involving the flow of fluids through a porous media, like the problems of enhanced oil recovery and geotechnical engineering, for example problems such as enhanced oil recovery and carbon di-oxide sequestration than one fluid is involved such as steam and oil in enhanced oil recovery. However before embarking
Bonito, Andrea
Finite Element Modeling of Suspended Particle Migration in Non-Newtonian Fluids
Shear-induced migration of particles is studied during the slow flow of suspensions of spheres (particle volume fraction {phi} = 0.50) in an inelastic but shear-thinning, suspending fluid in flow between counterrotating concentric cylinders, The conditions are such that nonhydrodynamic effects are negligible. The movement of particles away from the high shear rate region is more pronounced than in a Newtonian suspending liquid. We test a continuum constitutive model for the evolution of particle concentration in a flowing suspension proposed by Phillips et al. (1992) by using shear-thinning, suspending fluids. The fluid constitutive equation is Carreau-like in its shear-thinning behavior but also varies with the local particle concentration. The model is compared with the experimental data gathered with nuclear magnetic resonance (NMR) imaging.
Altobelli, S.; Baer, T.; Mondy, L.; Rao, R.; Stephens, T.
An overview of instability and fingering during immiscible fluid flow in porous and fractured media
Wetting front instability is an important phenomenon affecting fluid flow and contaminant transport in unsaturated soils and rocks. It causes the development of fingers which travel faster than would a uniform front and thus bypass much of the medium. Water saturation and solute concentration in such fingers tend to be higher than in the surrounding medium. During infiltration, fingering may cause unexpectedly rapid arrival of water and solute at the water-table. This notwithstanding, most models of subsurface flow and transport ignore instability and fingering. In this report, we survey the literature to assess the extent to which this may or may not be justified. Our overview covers experiments, theoretical studies, and computer simulations of instability and fingering during immiscible two-phase flow and transport, with emphasis on infiltration into soils and fractured rocks. Our description of instability in an ideal fracture (Hele-Shaw cell) includes an extension of existing theory to fractures and interfaces having arbitrary orientations in space. Our discussion of instability in porous media includes a slight but important correction of existing theory for the case of an inclined interface. We conclude by outlining some potential directions for future research. Among these, we single out the effect of soil and rock heterogeneities on instability and preferential flow as meriting special attention in the context of nuclear waste storage in unsaturated media.
Chen, G.; Neuman, S.P. [Univ. of Arizona, Tucson, AZ (United States). Dept. of Hydrology and Water Resources; Taniguchi, M. [Nara Univ. of Education (Japan). Dept. of Earth Sciences
Multiphase flow and control of fluid path in microsystems
Miniaturized chemical-systems are expected to have advantages of handling, portability, cost, speed, reproducibility and safety. Control of fluid path in small channels between processes in a chemical/biological network ...
Jhunjhunwala, Manish
Mass-Conserved Phase Field Models for Binary Fluids
Recently, phase field models are applied. 27 to study liquid crystal drop deformation in another fluid, liquid films, polymer nanocom-. 28 posites, and biofilms [5,�...
Flow and heat transfer of a third grade fluid past an exponentially stretching sheet with
Flow and heat transfer of a third grade fluid past an exponentially stretching sheet with partial-Newtonian boundary layer flow and heat transfer over an exponentially stretch- ing sheet with partial slip boundary. The heat transfer analysis has been carried out for two heating processes, namely (i) with prescribed sur
SUBCRITICAL INSTABILITIES IN PLANE COUETTE FLOW OF VISCO-ELASTIC FLUIDS Alexander N. Morozov of an eigenfunction of the linearized equations of motion becomes subcritically unstable, and the threshold value, subcritical instabilities, amplitude equation Introduction In the last decades, stability of flows of polymers
van Saarloos, Wim
Modelling of multiphase flow in ironmaking blast furnace
A mathematical model for the four-phase (gas, powder, liquid, and solids) flow in a two-dimensional ironmaking blast furnace is presented by extending the existing two-fluid flow models. The model describes the motion of gas, solid, and powder phases, based on the continuum approach, and implements the so-called force balance model for the flow of liquids, such as metal and slag in a blast furnace. The model results demonstrate a solid stagnant zone and dense powder hold-up region, as well as a dense liquid flow region that exists in the lower part of a blast furnace, which are consistent with the experimental observations reported in the literature. The simulation is extended to investigate the effects of packing properties and operational conditions on the flow and the volume fraction distribution of each phase in a blast furnace. It is found that solid movement has a significant effect on powder holdup distribution. Small solid particles and low porosity distribution are predicted to affect the fluid flow considerably, and this can cause deterioration in bed permeability. The dynamic powder holdup in a furnace increases significantly with the increase of powder diameter. The findings should be useful to better understand and control blast furnace operations.
Dong, X.F.; Yu, A.B.; Burgess, J.M.; Pinson, D.; Chew, S.; Zulli, P. [University of New South Wales, Sydney, NSW (Australia). School for Material Science and Engineering
Integrated Nozzle Flow, Spray, Combustion, & Emission Modeling...
Spray, Combustion, & Emission Modeling using KH-ACT Primary Breakup Model & Detailed Chemistry Integrated Nozzle Flow, Spray, Combustion, & Emission Modeling using KH-ACT Primary...
Nonlinear evolution of the magnetized Kelvin-Helmholtz instability: From fluid to kinetic modeling
The nonlinear evolution of collisionless plasmas is typically a multi-scale process, where the energy is injected at large, fluid scales and dissipated at small, kinetic scales. Accurately modelling the global evolution requires to take into account the main micro-scale physical processes of interest. This is why comparison of different plasma models is today an imperative task aiming at understanding cross-scale processes in plasmas. We report here the first comparative study of the evolution of a magnetized shear flow, through a variety of different plasma models by using magnetohydrodynamic (MHD), Hall-MHD, two-fluid, hybrid kinetic, and full kinetic codes. Kinetic relaxation effects are discussed to emphasize the need for kinetic equilibriums to study the dynamics of collisionless plasmas in non trivial configurations. Discrepancies between models are studied both in the linear and in the nonlinear regime of the magnetized Kelvin-Helmholtz instability, to highlight the effects of small scale processes on the nonlinear evolution of collisionless plasmas. We illustrate how the evolution of a magnetized shear flow depends on the relative orientation of the fluid vorticity with respect to the magnetic field direction during the linear evolution when kinetic effects are taken into account. Even if we found that small scale processes differ between the different models, we show that the feedback from small, kinetic scales to large, fluid scales is negligible in the nonlinear regime. This study shows that the kinetic modeling validates the use of a fluid approach at large scales, which encourages the development and use of fluid codes to study the nonlinear evolution of magnetized fluid flows, even in the collisionless regime.
Henri, P. [Dipartimento di Fisica, Universit� di Pisa, Largo Pontecorvo 3, 56127 Pisa (Italy) [Dipartimento di Fisica, Universit� di Pisa, Largo Pontecorvo 3, 56127 Pisa (Italy); Universit� de Nice Sophia Antipolis, CNRS, Observatoire de la C�te d'Azur, BP 4229 06304, Nice Cedex 4 (France); Cerri, S. S. [Dipartimento di Fisica, Universit� di Pisa, Largo Pontecorvo 3, 56127 Pisa (Italy) [Dipartimento di Fisica, Universit� di Pisa, Largo Pontecorvo 3, 56127 Pisa (Italy); Max-Planck-Institut f�r Plasmaphysik, EURATOM Association, D-85748 Garching (Germany); Califano, F.; Pegoraro, F. [Dipartimento di Fisica, Universit� di Pisa, Largo Pontecorvo 3, 56127 Pisa (Italy)] [Dipartimento di Fisica, Universit� di Pisa, Largo Pontecorvo 3, 56127 Pisa (Italy); Rossi, C. [Dipartimento di Fisica, Universit� di Pisa, Largo Pontecorvo 3, 56127 Pisa (Italy) [Dipartimento di Fisica, Universit� di Pisa, Largo Pontecorvo 3, 56127 Pisa (Italy); LPP-CNRS, Ecole Polytechnique, UPMC, Universit� Paris VI, Universit� Paris XI, route de Saclay, 91128 Palaiseau (France); Faganello, M. [International Institute for Fusion Science/PIIM, UMR 7345 CNRS, Aix-Marseille University, 13397 Marseille (France)] [International Institute for Fusion Science/PIIM, UMR 7345 CNRS, Aix-Marseille University, 13397 Marseille (France); �ebek, O. [Astronomical Institute and Institute of Atmospheric Physics, AS CR Bocni II/1401, CZ-14131 Prague, Czech Republic and Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University in Prague, B?ehov� 7, 11519 Prague (Czech Republic)] [Astronomical Institute and Institute of Atmospheric Physics, AS CR Bocni II/1401, CZ-14131 Prague, Czech Republic and Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University in Prague, B?ehov� 7, 11519 Prague (Czech Republic); Tr�vn�?ek, P. M. [Space Sciences Laboratory, University of California Berkeley, 7 Gauss Way, Berkeley, California 94720, USA and Astronomical Institute and Institute of Atmospheric Physics, AS CR Bocni II/1401, CZ-14131 Prague (Czech Republic)] [Space Sciences Laboratory, University of California Berkeley, 7 Gauss Way, Berkeley, California 94720, USA and Astronomical Institute and Institute of Atmospheric Physics, AS CR Bocni II/1401, CZ-14131 Prague (Czech Republic); Hellinger, P. [Astronomical Institute and Institute of Atmospheric Physics, AS CR Bocni II/1401, CZ-14131 Prague (Czech Republic)] [Astronomical Institute and Institute of Atmospheric Physics, AS CR Bocni II/1401, CZ-14131 Prague (Czech Republic); and others
Role of viscoelasticity and non-linear rheology in flows of complex fluids at high deformation rates
We combine pressure, velocimetry and birefringence measurements to study three phenomena for which the fluid rheology plays a dominant role: 1) shear banding in micellar fluids, 2) extension-dominated flows in microfluidic ...
Ober, Thomas J. (Thomas Joseph)
Ice Shelves as Floating Channel Flows of Viscous Power-Law Fluids
We attempt to better understand the flow of marine ice sheets. Treating ice as a viscous shear-thinning power law fluid, we develop an asymptotic (late-time) theory in two cases - the presence or absence of contact with sidewalls. Most real-world situations fall somewhere between the two extreme cases considered. When sidewalls are absent, we obtain the equilibrium grounding line thickness using a simple computer model and have an analytic approximation. For shelves in contact with sidewalls, we obtain an asymptotic theory, valid for long shelves. Our theory is based on the velocity profile across the channel being a generalised version of Poiseuille flow, which works when lateral shear dominates the force balance. We determine when this is. We conducted experiments using a laboratory model for ice. This was a suspension of xanthan in water, at a concentration of 0.5% by mass. The lab model has $n \\approx 3.8$ (similar to that of ice). The experiments agreed extremely well with our theories for all relevant p...
Banik, Indranil
Calculation of unsteady turbulent flow around obstacles using the large eddy simulation turbulence model
The premise of the work presented here is to use a common analytical tool, Computational Fluid Dynamics (CFD), along with a prevalent turbulence model, Large Eddy Simulation (LES), to study the flow past rectangular cylinders. In an attempt to use...
Helton, Donald McLean
U-Sr isotopic speedometer: Fluid flow and chemical weatheringrates inaquifers
Both chemical weathering rates and fluid flow are difficultto measure in natural systems. However, these parameters are critical forunderstanding the hydrochemical evolution of aquifers, predicting thefate and transport of contaminants, and for water resources/water qualityconsiderations. 87Sr/86Sr and (234U/238U) activity ratios are sensitiveindicators of water-rock interaction, and thus provide a means ofquantifying both flow and reactivity. The 87Sr/86Sr values in groundwaters are controlled by the ratio of the dissolution rate to the flowrate. Similarly, the (234U/238U) ratio of natural ground waters is abalance between the flow rate and the dissolution of solids, andalpha-recoil loss of 234U from the solids. By coupling these two isotopesystems it is possible to constrain both the long-term (ca. 100's to1000's of years) flow rate and bulk dissolution rate along the flow path.Previous estimates of the ratio of the dissolution rate to theinfiltration flux from Sr isotopes (87Sr/86Sr) are combined with a modelfor (234U/238U) to constrain the infiltration flux and dissolution ratefor a 70-m deep vadose zone core from Hanford, Washington. The coupledmodel for both (234U/238U) ratios and the 87Sr/86Sr data suggests aninfiltration flux of 5+-2 mm/yr, and bulk silicate dissolution ratesbetween 10-15.7 and 10-16.5 mol/m2/s. The process of alpha-recoilenrichment, while primarily responsible for the observed variation in(234U/238U) of natural systems, is difficult to quantify. However, therate of this process in natural systems affects the interpretation ofmost U-series data. Models for quantifying the alpha-recoil loss fractionbased on geometric predictions, surface area constraints, and chemicalmethods are also presented. The agreement between the chemical andtheoretical methods, such as direct measurement of (234U/238U) of thesmall grain size fraction and geometric calculations for that sizefraction, is quite good.
Maher, Kate; DePaolo, Donald J.; Christensen, John N.
Similarity Flow Solutions of a Non-Newtonian Power-law Fluid
In this paper we present a mathematical analysis for a steady-state laminar boundary layer flow, governed by the Ostwald-de Wael power-law model of an incompressible non- Newtonian fluid past a semi-infinite power-law stretched flat plate with uniform free stream velocity. A generalization of the usual Blasius similarity transformation is used to find similarity solutions [1]. Under appropriate assumptions, partial differential equations are transformed into an autonomous third-order nonlinear degenerate ordinary differential equation with boundary conditions. Using a shooting method, we establish the existence of an infinite number of global unbounded solutions. The asymptotic behavior is also discussed. Some properties of those solutions depend on the viscosity power-law index.
Guedda, Mohamed
Stochastic models for turbulent reacting flows
The goal of this program is to develop and apply stochastic models of various processes occurring within turbulent reacting flows in order to identify the fundamental mechanisms governing these flows, to support experimental studies of these flows, and to further the development of comprehensive turbulent reacting flow models.
Kerstein, A. [Sandia National Laboratories, Livermore, CA (United States)
Multiscale modeling for fluid transport in nanosystems.
Atomistic-scale behavior drives performance in many micro- and nano-fluidic systems, such as mircrofludic mixers and electrical energy storage devices. Bringing this information into the traditionally continuum models used for engineering analysis has proved challenging. This work describes one such approach to address this issue by developing atomistic-to-continuum multi scale and multi physics methods to enable molecular dynamics (MD) representations of atoms to incorporated into continuum simulations. Coupling is achieved by imposing constraints based on fluxes of conserved quantities between the two regions described by one of these models. The impact of electric fields and surface charges are also critical, hence, methodologies to extend finite-element (FE) MD electric field solvers have been derived to account for these effects. Finally, the continuum description can have inconsistencies with the coarse-grained MD dynamics, so FE equations based on MD statistics were derived to facilitate the multi scale coupling. Examples are shown relevant to nanofluidic systems, such as pore flow, Couette flow, and electric double layer.
Lee, Jonathan W.; Jones, Reese E.; Mandadapu, Kranthi Kiran; Templeton, Jeremy Alan; Zimmerman, Jonathan A.
NMRI methods for characterizing fluid flow in porous media
in the measurement and the prediction of flow permeability in rocks. We have investigated the application of Nuclear Magnetic Resonance Imaging to velocity measurement. A stimulated echo pulse field gradient approach was proposed to measure the localized velocity...
Yao, Xiaoli
Porosity, Permeability, And Fluid Flow In The Yellowstone Geothermal...
section of the 0.6-Ma Lava Creek ash-flow tuff. In this core, the degree of welding appears to be responsible for most of the variations in porosity, matrix...
A MEMS BODY FLUID FLOW SENSOR Ellis Meng1
for its stability, accuracy, and high temperature coefficient of resistivity (TCR). Additional packaging the device using compressed air. The flow rate is adjusted by a metering valve and calibrated using
Meng, Ellis
On the influence of an absorption term in incompressible fluid flows
|, they approximate the Ostwald-de Waele model for power law fluids, very often used to model non-Newtonian fluids and q as follows: Newtonian if µ0 > 0 and µ1 = 0 Ostwald-de Waele if µ0 = 0 and µ1 > 0 Bingham
Lisbon, University of
Fluid dynamics of dilatant fluid
Dense mixture of granules and liquid often shows a sever shear thickening and is called a dilatant fluid. We construct a fluid dynamics model for the dilatant fluid by introducing a phenomenological state variable for a local state of dispersed particles. With simple assumptions for an equation of the state variable, we demonstrate that the model can describe basic features of the dilatant fluid such as the stress-shear rate curve that represents discontinuous severe shear thickening, hysteresis upon changing shear rate, instantaneous hardening upon external impact. Analysis of the model reveals that the shear thickening fluid shows an instability in a shear flow for some regime and exhibits {\\it the shear thickening oscillation}, i.e. the oscillatory shear flow alternating between the thickened and the relaxed states. Results of numerical simulations are presented for one and two-dimensional systems.
Hiizu Nakanishi; Shin-ichiro Nagahiro; Namiko Mitarai
This document reports progress of this research effort in identifying possible relationships and defining dependencies between macroscopic reservoir parameters strongly affected by microscopic flow dynamics and production well performance in tight gas sand reservoirs. Based on a critical review of the available literature, a better understanding of the main weaknesses of the current state of the art of modeling and simulation for tight sand reservoirs has been reached. Progress has been made in the development and implementation of a simple reservoir simulator that is still able to overcome some of the deficiencies detected. The simulator will be used to quantify the impact of microscopic phenomena in the macroscopic behavior of tight sand gas reservoirs. Phenomena such as, Knudsen diffusion, electro-kinetic effects, ordinary diffusion mechanisms and water vaporization are being considered as part of this study. To date, the adequate modeling of gas slippage in porous media has been determined to be of great relevance in order to explain unexpected fluid flow behavior in tight sand reservoirs.
Maria Cecilia Bravo; Mariano Gurfinkel
Heat transfer and fluid flow characteristics in various micro devices for the development of micro absorption heat pump systems.
??This thesis presents a series of studies on heat transfer and fluid flow characteristics in various micro devices for the development of micro absorption heat� (more)
Hu, Jinshan
Microscale fluid flow induced by thermoviscous expansion along a traveling wave
The thermal expansion of a fluid combined with a temperature-dependent viscosity introduces nonlinearities in the Navier-Stokes equations unrelated to the convective momentum current. The couplings generate the possibility for net fluid flow at the microscale controlled by external heating. This novel thermo-mechanical effect is investigated for a thin fluid chamber by a numerical solution of the Navier-Stokes equations and analytically by a perturbation expansion. A demonstration experiment confirms the basic mechanism and quantitatively validates our theoretical analysis.
Franz M. Weinert; Jonas A. Kraus; Thomas Franosch; Dieter Braun
Method and apparatus for simultaneous determination of fluid mass flow rate, mean velocity and density
This invention relates to a new method and new apparatus for determining fluid mass flowrate and density. In one aspect of the invention, the fluid is passed through a straight cantilevered tube in which transient oscillation has been induced, thus generating Coriolis damping forces on the tube. The decay rate and frequency of the resulting damped oscillation are measured, and the fluid mass flowrate and density are determined therefrom. In another aspect of the invention, the fluid is passed through the cantilevered tube while an electrically powered device imparts steady-state harmonic excitation to the tube. This generates Coriolis tube-damping forces which are dependent on the mass flowrate of the fluid. Means are provided to respond to incipient flow-induced changes in the amplitude of vibration by changing the power input to the excitation device as required to sustain the original amplitude of vibration. The fluid mass flowrate and density are determined from the required change in power input. The invention provides stable, rapid, and accurate measurements. It does not require bending of the fluid flow.
Hamel, William R. (Farragut, TN)
Energy of eigen-modes in magnetohydrodynamic flows of ideal fluids
Analytical expression for energy of eigen-modes in magnetohydrodynamic flows of ideal fluids is obtained. It is shown that the energy of unstable modes is zero, while the energy of stable oscillatory modes (waves) can assume both positive and negative values. Negative energy waves always correspond to non-symmetric eigen-modes -- modes that have a component of wave-vector along the equilibrium velocity. These results suggest that all non-symmetric instabilities in ideal MHD systems with flows are associated with coupling of positive and negative energy waves. As an example the energy of eigen-modes is calculated for incompressible conducting fluid rotating in axial magnetic field.
I. V. Khalzov; A. I. Smolyakov; V. I. Ilgisonis
Development of one-dimensional computational fluid dynamics code 'GFLOW' for groundwater flow and contaminant transport analysis
Prediction of groundwater movement and contaminant transport in soil is an important problem in many branches of science and engineering. This includes groundwater hydrology, environmental engineering, soil science, agricultural engineering and also nuclear engineering. Specifically, in nuclear engineering it is applicable in the design of spent fuel storage pools and waste management sites in the nuclear power plants. Ground water modeling involves the simulation of flow and contaminant transport by groundwater flow. In the context of contaminated soil and groundwater system, numerical simulations are typically used to demonstrate compliance with regulatory standard. A one-dimensional Computational Fluid Dynamics code GFLOW had been developed based on the Finite Difference Method for simulating groundwater flow and contaminant transport through saturated and unsaturated soil. The code is validated with the analytical model and the benchmarking cases available in the literature. (authors)
Rahatgaonkar, P. S.; Datta, D.; Malhotra, P. K.; Ghadge, S. G. [Nuclear Power Corporation of India Ltd., R-2, Ent. Block, Nabhikiya Urja Bhavan, Anushakti Nagar, Mumbai - 400 094 (India)
Computational Methods for Analyzing Fluid Flow Dynamics from Digital Imagery
The main goal (long term) of this work is to perform computational dynamics analysis and quantify uncertainty from vector fields computed directly from measured data. Global analysis based on observed spatiotemporal evolution is performed by objective function based on expected physics and informed scientific priors, variational optimization to compute vector fields from measured data, and transport analysis proceeding with observations and priors. A mathematical formulation for computing flow fields is set up for computing the minimizer for the problem. An application to oceanic flow based on sea surface temperature is presented.
Luttman, A.
Peristaltic Transport of a Rheological Fluid: Model for Movement of Food Bolus Through Esophagus
Fluid mechanical peristaltic transport through esophagus has been of concern in the paper. A mathematical model has been developed with an aim to study the peristaltic transport of a rheological fluid for arbitrary wave shapes and tube lengths. The Ostwald-de Waele power law of viscous fluid is considered here to depict the non-Newtonian behaviour of the fluid. The model is formulated and analyzed with the specific aim of exploring some important information concerning the movement of food bolus through the esophagus. The analysis has been carried out by using lubrication theory. The study is particularly suitable for cases where the Reynolds number is small. The esophagus is treated as a circular tube through which the transport of food bolus takes places by periodic contraction of the esophageal wall. Variation of different variables concerned with the transport phenomena such as pressure, flow velocity, particle trajectory and reflux are investigated for a single wave as well as for a train of periodic peristaltic waves. Locally variable pressure is seen to be highly sensitive to the flow index `n'. The study clearly shows that continuous fluid transport for Newtonian/rheological fluids by wave train propagation is much more effective than widely spaced single wave propagation in the case of peristaltic movement of food bolus in the esophagus.
J. C. Misra; S. Maiti
1. INTRODUCTION Fluid flows are often so complicated that laboratory
with vertical stratification. For a single-hemisphere basin, self-sustained oscillations of the flow and period of the oscillations are partly determined by the energy avail- able for vertical mixing if v, University of Stockholm, Sweden. 4Department of Geosciences, University of Bremen, Germany. 5Climate
Nilsson, Johan
Analytical solutions for the flow of Carreau and Cross fluids in circular pipes and thin slits
In this paper, analytical expressions correlating the volumetric flow rate to the pressure drop are derived for the flow of Carreau and Cross fluids through straight rigid circular uniform pipes and long thin slits. The derivation is based on the application of Weissenberg-Rabinowitsch-Mooney-Schofield method to obtain flow solutions for generalized Newtonian fluids through pipes and our adaptation of this method to the flow through slits. The derived expressions are validated by comparing their solutions to the solutions obtained from direct numerical integration. They are also validated by comparison to the solutions obtained from the variational method which we proposed previously. In all the investigated cases, the three methods agree very well. The agreement with the variational method also lends more support to this method and to the variational principle which the method is based upon.
Sochi, Taha
, which is a novel approach in Microfluidics. To verify the developed models, several testbeds have been
Bahrami, Majid
Application of x-ray microtomography to environmental fluid flow D. Wildenschild*a,c
environmental processes are controlled by the micro-scale interaction of water and air with the solid phaseApplication of x-ray microtomography to environmental fluid flow problems D. Wildenschild*a,c , K resource management, contaminant remediation, and agriculture. Many of these physical processes operative
Wildenschild, Dorthe
Hydrothermal dolomites in SW Sardinia (Italy): evidence for a widespread late-Variscan fluid flow event
Hydrothermal dolomites in SW Sardinia (Italy): evidence for a widespread late-Variscan fluid flow, the Cambrian carbonates underwent ductile deformation and greenschist facies metamorphism. The same is true-temperature metamorphic rocks within the overlying nappes. It is assumed that a late-Variscan hydrothermal event, which
Boni, Maria
A conservative Lagrangian scheme for solving compressible fluid flows with multiple internal energy equations
A conservative Lagrangian scheme for solving compressible fluid flows with multiple internal energy. In some of these ap- plications, multiple internal energy equations such as those for electron, ion developed which are designed to solve the internal energy equation directly. These schemes can be easily
Shu, Chi-Wang
3D MHD Free Surface Fluid Flow Simulation Based on Magnetic-Field Induction Equations
1 3D MHD Free Surface Fluid Flow Simulation Based on Magnetic-Field Induction Equations H.L. HUANG firstname.lastname@example.com Abstract: The purpose of this paper is to present our recent efforts on 3D MHD-plane magnetic field configurations have shown that 3D MHD effects from a surface normal field gradient cause
California at Los Angeles, University of
Coating Flows of Non-Newtonian Fluids: Weakly and Strongly Elastic Limits
Coating Flows of Non-Newtonian Fluids: Weakly and Strongly Elastic Limits J. Ashmore(1,a), A.Q. Shen(1,b), H.P. Kavehpour(2,c), H.A. Stone(1) & G.H. McKinley(2) 1: Division of Engineering and Applied of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139 (a): Current address: TIAX
Dynamics of a confined dusty fluid in a sheared ion flow
Dynamics of an isothermally driven dust fluid is analyzed which is confined in an azimuthally symmetric cylindrical setup by an effective potential and is in equilibrium with an unconfined sheared flow of a streaming plasma. Cases are analyzed where the confining potential constitutes a barrier for the driven fluid, limiting its spatial extension and boundary velocity. The boundary effects entering the formulation are characterized by applying the appropriate boundary conditions and a range of solutions exhibiting single and multiple vortex are obtained. The equilibrium solutions considered in the cylindrical setup feature a transition from single to multiple vortex state of the driven flow. Effects of (i) the variation in dust viscosity, (ii) coupling between the driving and the driven fluid, and (iii) a friction determining the equilibrium dynamics of the driven system are characterized.
Laishram, Modhuchandra; Sharma, Devendra; Kaw, Predhiman K. [Institute for Plasma Research, Bhat, Gandhinagar 382428 (India)
Device and method for measuring multi-phase fluid flow in a conduit having an abrupt gradual bend
A system is described for measuring fluid flow in a conduit having an abrupt bend. The system includes pressure transducers, one disposed in the conduit at the inside of the bend and one or more disposed in the conduit at the outside of the bend but spaced a distance therefrom. The pressure transducers measure the pressure of fluid in the conduit at the locations of the pressure transducers and this information is used by a computational device to calculate fluid flow rate in the conduit. For multi-phase fluid, the density of the fluid is measured by another pair of pressure transducers, one of which is located in the conduit elevationally above the other. The computation device then uses the density measurement along with the fluid pressure measurements, to calculate fluid flow. 1 fig.
Statistical mechanical theory for steady-state systems. III. Heat flow in a Lennard-Jones fluid
Statistical mechanical theory for steady-state systems. III. Heat flow in a Lennard-Jones fluid March 2005; accepted 4 May 2005; published online 28 June 2005 A statistical mechanical theory for heat distribution for heat flow down an imposed thermal gradient is tested with simulations of a Lennard-Jones fluid
Attard, Phil
Flow of mantle fluids through the ductile lower crust: Heliumisotope trends
Heat and mass are injected into the shallow crust when mantle fluids are able to flow through the ductile lower crust. Minimum 3He/4He ratios in surface fluids from the northern Basin and Range province, western North America increase systematically from low, crustal values in the east to high, mantle values in the west, a regional trend that correlates with the rates of active crustal deformation. The highest ratios occur where the extension and shear strain rates are greatest. The correspondence of helium isotope ratios and active trans-tensional deformation indicates a deformation enhanced permeability and that mantle fluids can penetrate the ductile lithosphere in regions even where there is no significant magmatism. Superimposed on the regional trend are local, high-{sup 3}He/{sup 4}He anomalies signifying hidden magmatic activity and/or deep fluid production with locally enhanced permeability, identifying zones with high resource potential, particularly for geothermal energy development.
Kennedy, B. Mack; van Soest, Matthijs C.
Exact Solutions for a Rotational Flow of Generalized Second Grade Fluids Through a Circular Cylinder
In this note the velocity field and the associated tangential stress corresponding to the rotational flows of a generalized second grade fluid within an infinite circular cylinder are determined by means of the Laplace and Hankel transforms. At time t=0 the fluid is at rest and the motion is produced by the rotation of the cylinder, around its axis, with the angular velocity $\\Omega.t$. The velocity field and the adequate shear stress are presented under integral and series forms in terms of the generalized G-functions. Furthermore, they are presented as a sum between the Newtonian solutions and the adequate non-Newtonian contributions. The corresponding solutions for the ordinary second grade fluid and Newtonian fluid are obtained as particular cases of our solutions for $\\beta = 1$, respectively $\\alpha = 0$ and $\\beta = 1$.
Amir Mahmood; Saifullah; Qammar Rubab
A lattice mesoscopic model of dynamically heterogeneous fluids
We introduce a mesoscopic three-dimensional Lattice Boltzmann Model which attempts to mimick the physical features associated with cage effects in dynamically heterogeneous fluids. To this purpose, we extend the standard Lattice Boltzmann dynamics with self-consistent constraints based on the non-local density of the surrounding fluid. The resulting dynamics exhibits typical features of dynamic heterogeneous fluids, such as non-Gaussian density distributions and long-time relaxation. Due to its intrinsically parallel dynamics, and absence of statistical noise, the method is expected to compute significantly faster than molecular dynamics, Monte Carlo and lattice glass models.
A. Lamura; S. Succi
Classical analogous of quantum cosmological perfect fluid models
Quantization in the mini-superspace of a gravity system coupled to a perfect fluid, leads to a solvable model which implies singularity free solutions through the construction of a superposition of the wavefunctions. We show that such models are equivalent to a classical system where, besides the perfect fluid, a repulsive fluid with an equation of state $p_Q = \\rho_Q$ is present. This leads to speculate on the true nature of this quantization procedure. A perturbative analysis of the classical system reveals the condition for the stability of the classical system in terms of the existence of an anti-gravity phase.
Batista, A B; Gon�alves, S V B; Tossa, J
Model for the free-volume distributions of equilibrium fluids
We introduce and test via molecular simulation a simple model for predicting the manner in which interparticle interactions and thermodynamic conditions impact the single-particle free-volume distributions of equilibrium fluids. The model suggests a scaling relationship for the density-dependent behavior of the hard-sphere system. It also predicts how the second virial coefficients of fluids with short-range attractions affect their free-volume distributions.
William P. Krekelberg; Venkat Ganesan; Thomas M. Truskett
Investigation of aluminum surface cleaning using cavitating fluid flow
This paper investigates efficiency of specially designed atomizer used to spray water and cavitate microbubbles in water flow. Surface cleaning system was used to clean machined (grinded) aluminum surface from abrasive particles. It is established that cleaning efficiency depends on diameter of the diffuser, water pressure and distance between nozzle and metal surface. It is obtained that the best cleaning efficiency (100%) is achieved at pressure 36 bar, when diameter of diffuser is 0.4 mm and distance between nozzle and surface is 1 mm. It is also established that satisfactory cleaning efficiency (80%) is achieved not only when atomizer is placed closer to metal surface, but also at larger (120 mm) distances.
Ralys, Aurimas; Stri�ka, Vytautas; Mok�in, Vadim [Vilnius Gediminas Technical University, Faculty of Mechanics, Department of Machine Engineering, J. Basanavi?iaus str.28, 03224, Vilnius (Lithuania)
Toward compressed DMD: spectral analysis of fluid flows using sub-Nyquist-rate PIV data
Dynamic mode decomposition (DMD) is a powerful and increasingly popular tool for performing spectral analysis of fluid flows. However, it requires data that satisfy the Nyquist-Shannon sampling criterion. In many fluid flow experiments, such data are impossible to capture. We propose a new approach that combines ideas from DMD and compressed sensing. Given a vector-valued signal, we take measurements randomly in time (at a sub-Nyquist rate) and project the data onto a low-dimensional subspace. We then use compressed sensing to identify the dominant frequencies in the signal and their corresponding modes. We demonstrate this method using two examples, analyzing both an artificially constructed test dataset and particle image velocimetry data collected from the flow past a cylinder. In each case, our method correctly identifies the characteristic frequencies and oscillatory modes dominating the signal, proving the proposed method to be a capable tool for spectral analysis using sub-Nyquist-rate sampling.
Tu, Jonathan H; Kutz, J Nathan; Shang, Jessica K
Hydrodynamical model for $J/?$ suppression and elliptic flow
In a hydrodynamic model, we have studied $J/\\psi$ suppression and elliptic flow in Au+Au collisions at RHIC energy $\\sqrt{s}$=200 GeV. At the initial time, $J/\\psi$'s are randomly distributed in the fluid. As the fluid evolve in time, the free streaming $J/\\psi$'s are dissolved if the local fluid temperature exceeds a melting temperature $T_{J/\\psi}$. Sequential melting of charmonium states ($\\chi_c$, $\\psi\\prime$ and $J/\\psi$), with melting temperatures $T_{\\chi_c}=T_{\\psi\\prime} \\approx 1.2T_c$, $T_{J/\\psi} \\approx2T_c$ and feed-down fraction $F\\approx 0.3$, is consistent with the PHENIX data on $J/\\psi$ suppression and near zero elliptic flow for $J/\\psi$'s. It is also shown that the model will require substantial regeneration of charmoniums, if the charmonium states dissolve at temperature close to the critical temperature, $T_{\\chi_c}=T_{\\psi\\prime} \\leq T_c$, $T_{J/\\psi}\\approx1.2T_c$. The regenerated charmoniums will have positive elliptic flow.
A. K. Chaudhuri
Oscillatory motion based measurement method and sensor for measuring wall shear stress due to fluid flow
A shear stress sensor for measuring fluid wall shear stress on a test surface is provided. The wall shear stress sensor is comprised of an active sensing surface and a sensor body. An elastic mechanism mounted between the active sensing surface and the sensor body allows movement between the active sensing surface and the sensor body. A driving mechanism forces the shear stress sensor to oscillate. A measuring mechanism measures displacement of the active sensing surface relative to the sensor body. The sensor may be operated under periodic excitation where changes in the nature of the fluid properties or the fluid flow over the sensor measurably changes the amplitude or phase of the motion of the active sensing surface, or changes the force and power required from a control system in order to maintain constant motion. The device may be operated under non-periodic excitation where changes in the nature of the fluid properties or the fluid flow over the sensor change the transient motion of the active sensor surface or change the force and power required from a control system to maintain a specified transient motion of the active sensor surface.
Armstrong, William D. (Laramie, WY); Naughton, Jonathan (Laramie, WY); Lindberg, William R. (Laramie, WY)
Non-Invasive Characterization Of A Flowing Multi-Phase Fluid Using Ultrasonic Interferometry
A turnstile mechanism for fronts propagating in fluid flows
We consider the propagation of fronts in a periodically driven flowing medium. It is shown that the progress of fronts in these systems may be mediated by a turnstile mechanism akin to that found in chaotic advection. We first define the modified ("active") turnstile lobes according to the evolution of point sources across a transport boundary. We then show that the lobe boundaries may be constructed from stable and unstable \\emph{burning invariant manifolds}---one-way barriers to front propagation analogous to traditional invariant manifolds for passive advection. Because the burning invariant manifolds (BIMs) are one-dimensional curves in a three-dimensional ($xy\\theta$) phase space, their projection into $xy$-space exhibits several key differences from their advective counterparts: (lobe) areas are not preserved, BIMs may self-intersect, and an intersection between stable and unstable BIMs does not map to another such intersection. These differences must be accommodated in the correct construction of the new turnstile. As an application, we consider a lobe-based treatment protocol for protecting an ocean bay from an invading algae bloom.
John R. Mahoney; Kevin A. Mitchell
WHICH HYDRAULIC MODEL TO USE IN VERTICAL FLOW CONSTRUCTED WETLANDS? Ania Morvannoua , Nicolas-equilibrium model, preferential flow path, vertical flow constructed wetlands INTRODUCTION Constructed wetlands (CWs
Site-Scale Saturated Zone Flow Model
The purpose of this model report is to document the components of the site-scale saturated-zone flow model at Yucca Mountain, Nevada, in accordance with administrative procedure (AP)-SIII.lOQ, ''Models''. This report provides validation and confidence in the flow model that was developed for site recommendation (SR) and will be used to provide flow fields in support of the Total Systems Performance Assessment (TSPA) for the License Application. The output from this report provides the flow model used in the ''Site-Scale Saturated Zone Transport'', MDL-NBS-HS-000010 Rev 01 (BSC 2003 [162419]). The Site-Scale Saturated Zone Transport model then provides output to the SZ Transport Abstraction Model (BSC 2003 [164870]). In particular, the output from the SZ site-scale flow model is used to simulate the groundwater flow pathways and radionuclide transport to the accessible environment for use in the TSPA calculations. Since the development and calibration of the saturated-zone flow model, more data have been gathered for use in model validation and confidence building, including new water-level data from Nye County wells, single- and multiple-well hydraulic testing data, and new hydrochemistry data. In addition, a new hydrogeologic framework model (HFM), which incorporates Nye County wells lithology, also provides geologic data for corroboration and confidence in the flow model. The intended use of this work is to provide a flow model that generates flow fields to simulate radionuclide transport in saturated porous rock and alluvium under natural or forced gradient flow conditions. The flow model simulations are completed using the three-dimensional (3-D), finite-element, flow, heat, and transport computer code, FEHM Version (V) 2.20 (software tracking number (STN): 10086-2.20-00; LANL 2003 [161725]). Concurrently, process-level transport model and methodology for calculating radionuclide transport in the saturated zone at Yucca Mountain using FEHM V 2.20 are being carried out in the model report, ''Site-Scale Saturated Zone Transport'', MDL-NBS-HS-000010 Rev 01 (BSC 2003 [162419]). The velocity fields are calculated by the flow model, described herein, independent of the transport processes, and are then used as inputs to the transport model. Justification for this abstraction is presented in the model report, ''Saturated Zone Flow and Transport Model Abstraction'', MDL-NBS-HS-000021 (BSC 2003 [164870]).
G. Zyvoloski
and its effect on fluid flow is numerical simulation. A 3D finite difference numerical model is developed based on Darcy-Brinkman formulation (DBF). Using the developed simulator a flow-based inversion approach is implemented to understand the connectivity...
Izgec, Omer
Imaging, Characterizing, and Modeling of Fracture Networks and...
Imaging, Characterizing, and Modeling of Fracture Networks and Fluid Flow in EGS Reservoirs Imaging, Characterizing, and Modeling of Fracture Networks and Fluid Flow in EGS...
Numerical Simulation of Compositional Fluid Flow in Porous Media
variables is developed for modeling the enhanced oil recovery pro- cesses. A mixed #12;nite element method to predict the reservoir performance under various exploita- tion schemes. In many enhanced oil recovery. Computational results for two- and three-phase multi-component uid ow occurring in enhanced oil re- covery
Motion of a Viscoelastic Micellar Fluid Around a Cylinder: Flow and Fracture
We present an experimental study of the motion of a viscoelastic micellar material around a moving cylinder, which ranges in response from fluid-like flow to solid-like tearing and fracture, depending on the cylinder radius and velocity. The observation of viscoelastic crack propagation driven by the cylinder indicates an extremely low tear strength, approximately equal to the steady state surface tension of the fluid. At the highest speeds a driven crack is observed in front of the cylinder, propagating with a fluctuating speed equal on average to the cylinder speed, here as low as 5% of the elastic wave speed in the medium.
Joseph R. Gladden; Andrew Belmonte
J. Non-Newtonian Fluid Mech., 72 (1997) 7386 Start-up of flow of a FENE-fluid through a 4:1:4 constriction in
. Introduction Elastic fluids resist converging flow through an orifice, responding by increasing the pressure drop to good accuracy. As a further numerical convenience, we make the shape of the constriction round the flow through a small orifice in a large plate between two reservoirs. They used HPAM and PEO solutions
Hinch, John
A Beale-Kato-Majda breakdown criterion for an Oldroyd-B fluid in the creeping flow regime
We derive a criterion for the breakdown of solutions to the Oldroyd-B model in $\\R^3$ in the limit of zero Reynolds number (creeping flow). If the initial stress field is in the Sobolev space $H^m$, $m> 5/2$, then either a unique solution exists within this space indefinitely, or, at the time where the solution breaks down, the time integral of the $L^\\infty$-norm of the stress tensor must diverge. This result is analogous to the celebrated Beale-Kato-Majda breakdown criterion for the inviscid Eluer equations of incompressible fluids.
Raz Kupferman; Claude Mangoubi; Edriss S. Titi
Particle-fluid-structure interaction for debris flow impact on flexible barriers
Flexible barriers are increasingly used for the protection from debris flow in mountainous terrain due to their low cost and environmental impact. However, a numerical tool for rational design of such structures is still missing. In this work, a hybrid computational framework is presented, using a total Lagrangian formulation of the Finite Element Method (FEM) to represent a flexible barrier. The actions exerted on the structure by a debris flow are obtained from simultaneous simulations of the flow of a fluid-grain mixture, using two conveniently coupled solvers: the Discrete Element Method (DEM) governs the motion of the grains, while the free-surface non-Newtonian fluid phase is solved using the Lattice-Boltzmann Method (LBM). Simulations on realistic geometries show the dependence of the momentum transfer on the barrier on the composition of the debris flow, challenging typical assumptions made during the design process today. In particular, we demonstrate that both grains and fluid contribute in a non-negligible way to the momentum transfer. Moreover, we show how the flexibility of the barrier reduces its vulnerability to structural collapse, and how the stress is distributed on its fabric, highlighting potential weak points.
A. Leonardi; F. K. Wittel; M. Mendoza; R. Vetter; H. J. Herrmann
Method and apparatus for optical Doppler tomographic imaging of fluid flow velocity in highly scattering media
Optical Doppler tomography permits imaging of fluid flow velocity in highly scattering media. The tomography system combines Doppler velocimetry with high spatial resolution of partially coherent optical interferometry to measure fluid flow velocity at discrete spatial locations. Noninvasive in vivo imaging of blood flow dynamics and tissue structures with high spatial resolutions of the order of 2 to 10 microns is achieved in biological systems. The backscattered interference signals derived from the interferometer may be analyzed either through power spectrum determination to obtain the position and velocity of each particle in the fluid flow sample at each pixel, or the interference spectral density may be analyzed at each frequency in the spectrum to obtain the positions and velocities of the particles in a cross-section to which the interference spectral density corresponds. The realized resolutions of optical Doppler tomography allows noninvasive in vivo imaging of both blood microcirculation and tissue structure surrounding the vessel which has significance for biomedical research and clinical applications.
Nelson, John Stuart (Laguna Niguel, CA); Milner, Thomas Edward (Irvine, CA); Chen, Zhongping (Irvine, CA)
Viscous Quark-Gluon Plasma Model Through Fluid QCD Approach
A Lagrangian density for viscous quark-gluon plasma has been constructed within the fluid-like QCD framework. Gauge symmetry is preserved for all terms inside the Lagrangian, except for the viscous term. The transition mechanism from point particle field to fluid field, and vice versa, is discussed. The energy momentum tensor that is relevant for the gluonic plasma having the nature of fluid bulk of gluon sea is derived within the model. By imposing conservation law in the energy momentum tensor, shear viscosity appears as extractable from the equation.
T. P. Djun; B. Soegijono; T. Mart; L. T. Handoko
Numerical modeling of deep groundwater flow and heat transport in the Williston Basin
A numerical modeling approach has been used to evaluate quantitatively the effects of fluid flow on contemporary heat flow in an intracratonic basin. The authors have selected the Williston basin for this hydrodynamic study because of the opportunity it presents to assess the relation of deep groundwater flow to basin geothermics and the associated features of diagenesis and petroleum accumulation. The finite element method is used to solve the coupled equations of fluid flow and heat transport in two-dimensional sections of the basin. Both the fluid- and heat-flow regime are assumed to be at steady state, and the fluid flow is driven primarily by the water-table relief which is taken to be a subdued replica of land-surface topography. Buoyancy forces may also affect flow through fluid density gradients created by temperature and salinity effects. Three southwest-northwest oriented sections across the basin were modeled using available and estimated parameter data. The predicted flow patterns are most strongly affected by the topography, but the Devonian salt unit and Cretaceous shale unit exert some control. Cross-formational flow is especially important near the downdip, solution edge of the salt beds. Flow rates rarely exceed 0.5 m/year in the deep-central part of the basin, yet there does exist a marked effect on heat flow, albeit subdued by the blanket effect of the low-permeability Cretaceous shales. The regional effect of the topography-driven flow system is reflected in present-day salinity patterns and heat-flow data.
Garven, G.; Vigrass, L.
Computational fluid dynamics modeling of coal gasification in a pressurized spout-fluid bed
Computational fluid dynamics (CFD) modeling, which has recently proven to be an effective means of analysis and optimization of energy-conversion processes, has been extended to coal gasification in this paper. A 3D mathematical model has been developed to simulate the coal gasification process in a pressurized spout-fluid bed. This CFD model is composed of gas-solid hydrodynamics, coal pyrolysis, char gasification, and gas phase reaction submodels. The rates of heterogeneous reactions are determined by combining Arrhenius rate and diffusion rate. The homogeneous reactions of gas phase can be treated as secondary reactions. A comparison of the calculated and experimental data shows that most gasification performance parameters can be predicted accurately. This good agreement indicates that CFD modeling can be used for complex fluidized beds coal gasification processes. 37 refs., 7 figs., 5 tabs.
Zhongyi Deng; Rui Xiao; Baosheng Jin; He Huang; Laihong Shen; Qilei Song; Qianjun Li [Southeast University, Nanjing (China). Key Laboratory of Clean Coal Power Generation and Combustion Technology of Ministry of Education
On the 3D steady flow of a second grade fluid past an obstacle
We study steady flow of a second grade fluid past an obstacle in three space dimensions. We prove existence of solution in weighted Lebesgue spaces with anisotropic weights and thus existence of the wake region behind the obstacle. We use properties of the fundamental Oseen tensor together with results achieved in \\cite{Koch} and properties of solutions to steady transport equation to get up to arbitrarily small $\\ep$ the same decay as the Oseen fundamental solution.
Pawe? Konieczny; Ond?ej Kreml
Conservation Law Models for Traffic Flow
Conservation Law Models for Traffic Flow Alberto Bressan Mathematics Department, Penn State University http://www.math.psu.edu/bressan/ Alberto Bressan (Penn State) Scalar Conservation Laws 1 / 117 #12;Review of hyperbolic conservation laws Models of traffic flow, on a single road and on a network of roads
Bressan, Alberto
Long-wave models of thin film fluid dynamics
Centre manifold techniques are used to derive rationally a description of the dynamics of thin films of fluid. The derived model is based on the free-surface $\\eta(x,t)$ and the vertically averaged horizontal velocity $\\avu(x,t)$. The approach appears to converge well and has significant differences from conventional depth-averaged models.
A. J. Roberts
Numerical method for fluid flow and heat transfer in magnetohydrodynamic flow
A new numerical algorithm was developed to provide a fully detailed flow field in liquid metal MHD flow with a relatively large Hartmann number and interaction parameter. The algorithm includes the effects of advection and diffusion, and is capable of predicting momentum and heat transfer in MHD flows. Using this algorithm, an incompressible, viscous, three-dimensional MHD flow in a square duct is investigated at a low magnetic Reynolds number by means of the finite volume method. The velocity and temperature profiles are obtained in the developing region for constant wall temperature. The result shows that large velocities are obtained near the insulating walls parallel to the magnetic field. Also, near the perfectly conducting walls perpendicular to the field, a velocity profile like a Hartmann layer is obtained. In association with the velocity profiles, Nusselt number at the insulating walls (with side layer) is seen to be larger than that at the perfectly conducting walls (with Hartmann layer).
Kim, C.N.; Abdou, M.A.
Continued development of a semianalytical solution for two-phase fluid and heat flow in a porous medium
Over the past few years the authors have developed a semianalytical solution for transient two-phase water, air, and heat flow in a porous medium surrounding a constant-strength linear heat source, using a similarity variable {eta} = r/{radical}t. Although the similarity transformation approach requires a simplified geometry, all the complex physical mechanisms involved in coupled two-phase fluid and heat flow can be taken into account in a rigorous way, so that the solution may be applied to a variety of problems of current interest. The work was motivated by adverse to predict the thermohydrological response to the proposed geologic repository for heat-generating high-level nuclear wastes at Yucca Mountain, Nevada, in a partially saturated, highly fractured volcanic formation. The paper describes thermal and hydrologic conditions near the heat source; new features of the model; vapor pressure lowering; and the effective-continuum representation of a fractured/porous medium.
Doughty, C.; Pruess, K. [Lawrence Berkeley Lab., CA (United States)
Physiochemical Evidence of Faulting Processes and Modeling of Fluid in Evolving Fault Systems in Southern California
Our study targets recent (Plio-Pleistocene) faults and young (Tertiary) petroleum fields in southern California. Faults include the Refugio Fault in the Transverse Ranges, the Ellwood Fault in the Santa Barbara Channel, and most recently the Newport- Inglewood in the Los Angeles Basin. Subsurface core and tubing scale samples, outcrop samples, well logs, reservoir properties, pore pressures, fluid compositions, and published structural-seismic sections have been used to characterize the tectonic/diagenetic history of the faults. As part of the effort to understand the diagenetic processes within these fault zones, we have studied analogous processes of rapid carbonate precipitation (scaling) in petroleum reservoir tubing and manmade tunnels. From this, we have identified geochemical signatures in carbonate that characterize rapid CO2 degassing. These data provide constraints for finite element models that predict fluid pressures, multiphase flow patterns, rates and patterns of deformation, subsurface temperatures and heat flow, and geochemistry associated with large fault systems.
Boles, James [Professor
Modeling Fluid Flow in Natural Systems, Model Validation and Demonstration
Energy Savers [EERE]
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Office of Inspector General Office0-72.pdfGeorgeDoesn't32 MasterAcquisitiTechnologyPotomacRidgeMobileCladdings: Aand|
ES2A7 -Fluid Mechanics Example Classes Model Answers to Example Questions (Set III)
ES2A7 - Fluid Mechanics Example Classes Model Answers to Example Questions (Set III) Question 1 10610 40031.8 -- �?=�?= �? �? == APN RT d Question 2: Type of Fluid #12;Consider 2 identical vertical tubes are filled with the same height of fluid: A Newtonian fluid is used with tube X whereas a non-Newtonian fluid
Thomas, Peter J.
A Robust Four-Fluid Transient Flow Simulator as an Analysis and Decision Making Tool for Dynamic Kill Operation
The worst scenario of drilling operation is blowout which is uncontrolled flow of formation fluid into the wellbore. Blowouts result in environmental damage with potential risk of injuries and fatalities. Although not all blowouts result in disaster...
Haghshenas, Arash
The influence of fluid flow through granitic crust: a thermo-tectonic study in and on Mont Blanc
The influence of fluid flow through granitic crust: a thermo-tectonic study in and on Mont Blanc Tim Dempster, Cristina Persano and Zoe Shipton *email@example.com Granitic and gneissose within a evolving mountain zone, the metasomatic influence of fluids in granite gneiss and the resulting
Glasgow, University of
A photographic study of fluid flow theory for two-dimensional laminar flow around solid bodies
water flows through sides M, DC and ?9, these three sides can be t, rea ed s, insulated suri'aces in the heat conduction problems. A&sr drawing small circles and squares ix the tubes shown in 54 and using the resistance uxG. tp one can find that tube...
Lee, Wen Ho
Viscoelastic fluid flow in a 2D channel bounded above by a deformable finite thickness elastic wall
The steady flow of three viscoelastic fluids (Oldroyd-B, FENE-P, and Owens model for blood) in a two-dimensional channel, partly bound by a deformable, finite thickness neo-Hookean solid, is computed. The limiting Weissenberg number beyond which computations fail to converge is found to increase with increasing dimensionless solid elasticity parameter {\\Gamma}, following the trend Owens > FENE- P > Oldroyd-B. The highly shear thinning nature of Owens model leads to the elastic solid always collapsing into the channel, for the wide range of values of {\\Gamma} considered here. In the case of the FENE-P and Oldroyd-B models, however, the fluid-solid interface can be either within the channel, or bulge outwards, depending on the value of {\\Gamma}. This behaviour differs considerably from predictions of earlier models that treat the deformable solid as a zero-thickness membrane, in which case the membrane always lies within the channel. The capacity of the solid wall to support both pressure and shear stress, in c...
Chakraborty, Debadi
Modeling complex biological flows in multi-scale systems using the APDEC framework
Modeling complex biological flows in multi-scale systems using the APDEC framework David Trebotich methods are based on higher-order finite difference methods in complex geometry with adaptivity-mail: email@example.com Abstract. We have developed advanced numerical algorithms to model biological fluids
Status of the TOUGH-FLAC simulator and recent applications related to coupled fluid flow and crustal deformations
This paper presents recent advancement in and applications of TOUGH-FLAC, a simulator for multiphase fluid flow and geomechanics. The TOUGH-FLAC simulator links the TOUGH family multiphase fluid and heat transport codes with the commercial FLAC{sup 3D} geomechanical simulator. The most significant new TOUGH-FLAC development in the past few years is a revised architecture, enabling a more rigorous and tight coupling procedure with improved computational efficiency. The applications presented in this paper are related to modeling of crustal deformations caused by deep underground fluid movements and pressure changes as a result of both industrial activities (the In Salah CO{sub 2} Storage Project and the Geysers Geothermal Field) and natural events (the 1960s Matsushiro Earthquake Swarm). Finally, the paper provides some perspectives on the future of TOUGH-FLAC in light of its applicability to practical problems and the need for high-performance computing capabilities for field-scale problems, such as industrial-scale CO{sub 2} storage and enhanced geothermal systems. It is concluded that despite some limitations to fully adapting a commercial code such as FLAC{sup 3D} for some specialized research and computational needs, TOUGH-FLAC is likely to remain a pragmatic simulation approach, with an increasing number of users in both academia and industry.
Rutqvist, J.
Viscous potential flow analysis of electrified miscible finitely conducting fluid through porous media
In this work, a viscous potential flow analysis is used to investigate capillary surface waves between two horizontal finite fluid layers. The two layers have finite conductivities and admit mass and heat transfer. A general dispersion relation is derived. The presence of finite conductivities together with the dielectric permeabilities makes the horizontal electric field play a dual role in the stability criterion. The phenomenon of negative viscosity is observed. A new growth rate parameter, depending on the kinematical viscosity of the lower fluid layer, is found and has a stabilizing effect on the unstable modes. The growth rates and neutral stability curve are given and applied to air-water interface. The effects of various parameters are discussed for the Kelvin-Helmholtz and the Rayleigh-Taylor instabilities.
Obied Allah, M. H. [Department of Mathematics, Faculty of Science, Assiut University, Assiut (Egypt)
TOUGH2: A general-purpose numerical simulator for multiphase fluid and heat flow
TOUGH2 is a numerical simulation program for nonisothermal flows of multicomponent, multiphase fluids in porous and fractured media. The chief applications for which TOUGH2 is designed are in geothermal reservoir engineering, nuclear waste disposal, and unsaturated zone hydrology. A successor to the TOUGH program, TOUGH2 offers added capabilities and user features, including the flexibility to handle different fluid mixtures, facilities for processing of geometric data (computational grids), and an internal version control system to ensure referenceability of code applications. This report includes a detailed description of governing equations, program architecture, and user features. Enhancements in data inputs relative to TOUGH are described, and a number of sample problems are given to illustrate code applications. 46 refs., 29 figs., 12 tabs.
Pruess, K.
Micro-macro models for viscoelastic fluids: modelling, mathematics and numerics
This paper is an introduction to the modelling of viscoelastic fluids, with an emphasis on micro-macro (or multiscale) models. Some elements of mathematical and numerical analysis are provided. These notes closely follow the lectures delivered by the second author at the Chinese Academy of Science during the Workshop "Stress Tensor Effects on Fluid Mechanics", in January 2010.
C. Le Bris; T. Leli�vre
Energy Flow Models for the Steel Industry
each step is calibrated against Commerce Dept. data. Third, a detailed energy flow model is presented for coke ovens and blast furnaces, two very energy-intensive steps in our seven step model of steelmaking. This process-step model is calibrated...
Hyman, B.; Andersen, J. P.
GROUNDWATER FLOW MODELS C. P. Kumar
(Uttaranchal) 1.0 INTRODUCTION The use of groundwater models is prevalent in the field of environmental scienceGROUNDWATER FLOW MODELS C. P. Kumar Scientist `E1' National Institute of Hydrology Roorkee 247667, groundwater models are being applied to predict the transport of contaminants for risk evaluation. In general
Kumar, C.P.
Journal of Fluid Mechanics A furtive stare at an
Journal of Fluid Mechanics Focus luids on F A furtive stare at an intra-cellular flow T. M. SQUIRES of the fluid flow within individual living cells, which agree quantitatively with their fluid mechanical model. Introduction Nature has long inspired researchers in fluid mechanics to explore the mechanical strategies used
Goldstein, Raymond E.
Journal of Fluids and Structures 20 (2005) 129140 Blood flow and damage by the roller pumps during
Journal of Fluids and Structures 20 (2005) 129140 Blood flow and damage by the roller pumps during created in a centrifugal pump used for a cardiopulmonary bypass, little is known about the blood flow and consequent damage in a roller pump. A time- dependent moving boundary problem is solved in this paper
Luo, Xiaoyu
Subcritical Finite-Amplitude Solutions for Plane Couette Flow of Viscoelastic Fluids Alexander N. Morozov and Wim van Saarloos
Subcritical Finite-Amplitude Solutions for Plane Couette Flow of Viscoelastic Fluids Alexander N is shown to exhibit a purely elastic subcritical instability at a very small-Reynolds number in spite. In this Letter we show that visco- elastic plane Couette flow (PCF) exhibits a subcritical instability to finite
Bulletin of the Seismological Society of America, Vol. 94, No. 5, pp. 18171830, October 2004 Faulting Induced by Forced Fluid Injection and Fluid Flow Forced by
is a technique used to image the volume of rock stimulated by hydraulic fracturing (Al- bright and Pearson, 1982. The method has been applied in devel- oping hot dry rock reservoirs (e.g., Pine and Batchelor, 1984; House al., 2003). Beyond mapping gross structure and fluid-flow paths, rela- tive source location
Microgravity Flow Regime Transition Modeling
apparatus have been used in past flow regime mapping experiments such as Venturi, perforated pipe, annular, and t-junction mixers. The mixing apparatus used in a particular experiment determines the bubble size distribution at the inlet... pressure of 80 kPa was reported, however, the temperature was not. The orientation and location of the test section with respect to the aircraft are unknown. The mixing apparatus used in the experiment was a Venturi mixer. This data set does...
Shephard, Adam M.
The Properties of Confined Water and Fluid Flow at the Nanoscale
This project has been focused on the development of accurate computational tools to study fluids in confined, nanoscale geometries, and the application of these techniques to probe the structural and electronic properties of water confined between hydrophilic and hydrophobic substrates, including the presence of simple ions at the interfaces. In particular, we have used a series of ab-initio molecular dynamics simulations and quantum Monte Carlo calculations to build an understanding of how hydrogen bonding and solvation are modified at the nanoscale. The properties of confined water affect a wide range of scientific and technological problems - including protein folding, cell-membrane flow, materials properties in confined media and nanofluidic devices.
Schwegler, E; Reed, J; Lau, E; Prendergast, D; Galli, G; Grossman, J C; Cicero, G
Computational Fluid Dynamics (CFD) Modeling for High Rate Pulverized Coal Injection (PCI) into the Blast Furnace
Pulverized coal injection (PCI) into the blast furnace (BF) has been recognized as an effective way to decrease the coke and total energy consumption along with minimization of environmental impacts. However, increasing the amount of coal injected into the BF is currently limited by the lack of knowledge of some issues related to the process. It is therefore important to understand the complex physical and chemical phenomena in the PCI process. Due to the difficulty in attaining trus BF measurements, Computational fluid dynamics (CFD) modeling has been identified as a useful technology to provide such knowledge. CFD simulation is powerful for providing detailed information on flow properties and performing parametric studies for process design and optimization. In this project, comprehensive 3-D CFD models have been developed to simulate the PCI process under actual furnace conditions. These models provide raceway size and flow property distributions. The results have provided guidance for optimizing the PCI process.
Dr. Chenn Zhou
Determination of Transport Properties From Flowing Fluid Temperature LoggingIn Unsaturated Fractured Rocks: Theory And Semi-Analytical Solution
Flowing fluid temperature logging (FFTL) has been recently proposed as a method to locate flowing fractures. We argue that FFTL, backed up by data from high-precision distributed temperature sensors, can be a useful tool in locating flowing fractures and in estimating the transport properties of unsaturated fractured rocks. We have developed the theoretical background needed to analyze data from FFTL. In this paper, we present a simplified conceptualization of FFTL in unsaturated fractured rock, and develop a semianalytical solution for spatial and temporal variations of pressure and temperature inside a borehole in response to an applied perturbation (pumping of air from the borehole). We compare the semi-analytical solution with predictions from the TOUGH2 numerical simulator. Based on the semi-analytical solution, we propose a method to estimate the permeability of the fracture continuum surrounding the borehole. Using this proposed method, we estimated the effective fracture continuum permeability of the unsaturated rock hosting the Drift Scale Test (DST) at Yucca Mountain, Nevada. Our estimate compares well with previous independent estimates for fracture permeability of the DST host rock. The conceptual model of FFTL presented in this paper is based on the assumptions of single-phase flow, convection-only heat transfer, and negligible change in system state of the rock formation. In a sequel paper [Mukhopadhyay et al., 2008], we extend the conceptual model to evaluate some of these assumptions. We also perform inverse modeling of FFTL data to estimate, in addition to permeability, other transport parameters (such as porosity and thermal conductivity) of unsaturated fractured rocks.
Mukhopadhyay, Sumit; Tsang, Yvonne W.
Fluid mechanical peristaltic transport through esophagus has been of concern in the paper. A mathematical model has been developed with an aim to study the peristaltic transport of a rheological fluid for arbitrary wave shapes and tube lengths. The Ostwald-de Waele power law of viscous fluid is considered here to depict the non-Newtonian behaviour of the fluid. The model is formulated and analyzed with the specific aim of exploring some important information concerning the movement of food bolus through the esophagus. The analysis has been carried out by using lubrication theory. The study is particularly suitable for cases where the Reynolds number is small. The esophagus is treated as a circular tube through which the transport of food bolus takes places by periodic contraction of the esophageal wall. Variation of different variables concerned with the transport phenomena such as pressure, flow velocity, particle trajectory and reflux are investigated for a single wave as well as for a train of periodic per...
Misra, J C
Three-Dimensional Computational Fluid Dynamics Modeling of Solid Oxide Electrolysis Cells and Stacks
A three-dimensional computational fluid dynamics (CFD) electrochemical model has been created for detailed analysis of a high-temperature electrolysis stack (solid oxide fuel cells operated as electrolyzers). Inlet and outlet plenum flow distributions are discussed. Maldistribution of plena flow show deviations in per-cell operating conditions due to non-uniformity of species concentrations. Models have also been created to simulate experimental conditions and for code validation. Comparisons between model predictions and experimental results are discussed. Mass, momentum, energy, and species conservation and transport are provided via the core features of the commercial CFD code FLUENT. A solid-oxide fuel cell (SOFC) model adds the electrochemical reactions and loss mechanisms and computation of the electric field throughout the cell. The FLUENT SOFC user-defined subroutine was modified for this work to allow for operation in the electrolysis mode. Model results provide detailed profiles of temperature, Nernst potential, operating potential, activation over-potential, anode-side gas composition, cathode-side gas composition, current density and hydrogen production over a range of stack operating conditions. Variations in flow distribution, and species concentration are discussed. End effects of flow and per-cell voltage are also considered. Predicted mean outlet hydrogen and steam concentrations vary linearly with current density, as expected. Contour plots of local electrolyte temperature, current density, and Nernst potential indicate the effects of heat transfer, reaction cooling/heating, and change in local gas composition.
Grant Hawkes; James O'Brien; Carl Stoots; Stephen Herring
Evaluation of a CFD-model for simulation of simplified flow conditioners
Perforated plate flow conditioners are used to generate a fully developed turbulent flow profile upstream of an orifice meter. It is very time-consuming to measure the effect of a flow conditioner for different upstream flow profiles. Therefore a project is initiated to evaluate the performance of a computational fluid computer code for this purpose. If the code correctly predicts the flow characteristics downstream of more complex flow conditioners. In this study a k-{var_epsilon} CFD-model was used to predict the flow downstream of obstruction plates having one large or nine small holes. Both mean velocity, turbulent kinetic energy, k, and the dissipation rate of turbulent kinetic energy, {var_epsilon}, were calculated and compared against measured data. The results indicate that it is possible to predict the mean velocity well and that the accuracy of the predicted k and {var_epsilon} depends on the complexity of the flow.
Erdal, A. [Statoil/K-LAB, Haugesund (Norway); Torbergsen, L.E.; Rimestad, S.; Krogstad, P.A. [Norwegian Inst. of Technology, Trondheim (Norway)
High-heat-flux removal by phase-change fluid and particulate flow
A new concept based on particulate flow in which either or both the particulates and the fluid could undergo phase changes is proposed. The presence of particulates provides not only a mechanism for additional heat removal through phase change but also the potential for increasing the rate of heat transfer by enhancing convection through surface region/bulk [open quotes]mixing[close quotes], by enhancing radiation, particularly for high-temperature cases; and for the case of multiphase fluid, by enhancing the boiling process. One particularly interesting coolant system based on this concept is [open quotes]subcooled boiling water-ice particulate[close quotes] flow. A preliminary analysis of this coolant system is presented, the results of which indicate that such a coolant system is better applied for cooling of relatively small surface areas with high local heat fluxes, where a conventional cooling system would come short of providing the required heat removal at acceptable coolant pressure levels. 14 refs., 8 figs.
Gorbis, Z.R.; Raffray, A.R.; Abdou, M.A. (Univ. of California, Los Angeles (United States))
Computational fluid dynamics simulation of the air/suppressant flow in an uncluttered F18 engine nacelle
For the purposes of designing improved Halon-alternative fire suppression strategies for aircraft applications, Computational Fluid Dynamics (CFD) simulations of the air flow, suppressant transport, and air-suppressant mixing within an uncluttered F18 engine nacelle were performed. The release of inert gases from a Solid Propellant Gas Generator (SPGG) was analyzed at two different injection locations in order to understand the effect of injection position on the flow patterns and the mixing of air and suppression agent. An uncluttered engine nacelle was simulated to provide insight into the global flow features as well as to promote comparisons with previous nacelle fire tests and recent water tunnel tests which included little or no clutter. Oxygen concentration levels, fuel/air residence times that would exist if a small fuel leak were present, velocity contours, and streamline patterns are presented inside the engine nacelle. The numerical results show the influence of the gent release location on regions of potential flame extinction due to oxygen inerting and high flame strain. The occurrence of inflow through the exhaust ducts on the aft end of the nacelle is also predicted. As expected, the predicted oxygen concentration levels were consistently higher than the measured levels since a fire was not modeled in this analysis. Despite differences in the conditions of these simulations and the experiments, good agreement was obtained between the CFD predictions and the experimental measurements.
Lopez, A.R.; Gritzo, L.A.; Hassan, B.
There has been an increasing interest in probabilistic modeling of hydrogeologic systems. The classical approach to groundwater modeling has been deterministic in nature, where individual layers and formations are assumed to be uniformly homogeneous. Even in the case of complex heterogeneous systems, the heterogeneities describe the differences in parameter values between various layers, but not within any individual layer. In a deterministic model a single-number is assigned to each hydrogeologic parameter, given a particular scale of interest. However, physically there is no such entity as a truly uniform and homogeneous unit. Single-number representations or deterministic predictions are subject to uncertainties. The approach used in this work models such uncertainties with probabilistic parameters. The resulting statistical distributions of output variables are analyzed. A numerical algorithm, based on axiomatic principles of probability theory, performs arithmetic operations between probability distributions. Two subroutines are developed from the algorithm and incorporated into the computer program TERZAGI, which solves groundwater flow problems in saturated, multi-dimensional systems. The probabilistic computer program is given the name, PROGRES. The algorithm has been applied to study the following problems: one-dimensional flow through homogeneous media, steady-state and transient flow conditions, one-dimensional flow through heterogeneous media, steady-state and transient flow conditions, and two-dimensional steady-stte flow through heterogeneous media. The results are compared with those available in the literature.
Buscheck, Timothy Eric
Numerical schemes for dynamically orthogonal equations of stochastic fluid and ocean flows
The quantification of uncertainties is critical when systems are nonlinear and have uncertain terms in their governing equations or are constrained by limited knowledge of initial and boundary conditions. Such situations are common in multiscale, intermittent and non-homogeneous fluid and ocean flows. The dynamically orthogonal (DO) field equations provide an adaptive methodology to predict the probability density functions of such flows. The present work derives efficient computational schemes for the DO methodology applied to unsteady stochastic Navier-Stokes and Boussinesq equations, and illustrates and studies the numerical aspects of these schemes. Semi-implicit projection methods are developed for the mean and for the DO modes, and time-marching schemes of first to fourth order are used for the stochastic coefficients. Conservative second-order finite-volumes are employed in physical space with new advection schemes based on total variation diminishing methods. Other results include: (i) the definition of pseudo-stochastic pressures to obtain a number of pressure equations that is linear in the subspace size instead of quadratic; (ii) symmetric advection schemes for the stochastic velocities; (iii) the use of generalized inversion to deal with singular subspace covariances or deterministic modes; and (iv) schemes to maintain orthonormal modes at the numerical level. To verify our implementation and study the properties of our schemes and their variations, a set of stochastic flow benchmarks are defined including asymmetric Dirac and symmetric lock-exchange flows, lid-driven cavity flows, and flows past objects in a confined channel. Different Reynolds number and Grashof number regimes are employed to illustrate robustness. Optimal convergence under both time and space refinements is shown as well as the convergence of the probability density functions with the number of stochastic realizations.
Ueckermann, M.P., E-mail: firstname.lastname@example.com [Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Mass. Avenue, Cambridge, MA 02139 (United States); Lermusiaux, P.F.J., E-mail: email@example.com [Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Mass. Avenue, Cambridge, MA 02139 (United States)] [Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Mass. Avenue, Cambridge, MA 02139 (United States); Sapsis, T.P., E-mail: firstname.lastname@example.com [Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Mass. Avenue, Cambridge, MA 02139 (United States)
Review and selection of unsaturated flow models
Since the 1960`s, ground-water flow models have been used for analysis of water resources problems. In the 1970`s, emphasis began to shift to analysis of waste management problems. This shift in emphasis was largely brought about by site selection activities for geologic repositories for disposal of high-level radioactive wastes. Model development during the 1970`s and well into the 1980`s focused primarily on saturated ground-water flow because geologic repositories in salt, basalt, granite, shale, and tuff were envisioned to be below the water table. Selection of the unsaturated zone at Yucca Mountain, Nevada, for potential disposal of waste began to shift model development toward unsaturated flow models. Under the US Department of Energy (DOE), the Civilian Radioactive Waste Management System Management and Operating Contractor (CRWMS M&O) has the responsibility to review, evaluate, and document existing computer models; to conduct performance assessments; and to develop performance assessment models, where necessary. This document describes the CRWMS M&O approach to model review and evaluation (Chapter 2), and the requirements for unsaturated flow models which are the bases for selection from among the current models (Chapter 3). Chapter 4 identifies existing models, and their characteristics. Through a detailed examination of characteristics, Chapter 5 presents the selection of models for testing. Chapter 6 discusses the testing and verification of selected models. Chapters 7 and 8 give conclusions and make recommendations, respectively. Chapter 9 records the major references for each of the models reviewed. Appendix A, a collection of technical reviews for each model, contains a more complete list of references. Finally, Appendix B characterizes the problems used for model testing.
Reeves, M.; Baker, N.A.; Duguid, J.O. [INTERA, Inc., Las Vegas, NV (United States)
A model for transonic plasma flow
A linear, two-dimensional model of a transonic plasma flow in equilibrium is constructed and given an explicit solution in the form of a complex Laplace integral. The solution indicates that the transonic state can be solved as an elliptic boundary value problem, as is done in the numerical code FLOW [Guazzotto et al., Phys. Plasmas 11, 604 (2004)]. Moreover, the presence of a hyperbolic region does not necessarily imply the presence of a discontinuity or any other singularity of the solution.
Guazzotto, Luca, E-mail: email@example.com [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623 (United States)] [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623 (United States); Hameiri, Eliezer, E-mail: firstname.lastname@example.com [Courant Institute of Mathematical Sciences, New York University, New York, New York 10012 (United States)] [Courant Institute of Mathematical Sciences, New York University, New York, New York 10012 (United States)
Modeling gas flow through microchannels and nanopores Subrata Roya)
Plasma Dynamics Laboratory, Department of Mechanical Engineering Kettering University, Flint, Michigan microchannels and nanopores. Presented two-dimensional numerical results for Poiseuille flow of a simple fluid extensively used in our everyday life. Some MEMS devices have also been designed in the field of fluid applica
Analysis of Refrigerant Flow and Deformation for a Flexible Short-Tube using a Finite Element Model
reliability. Short-tubes have either a constant inner dia- meter flow channel or a tapered channel with a smallAbstract A finite element model was used to simulate single-phase flow of R-22 through flexible short-tubes. The numerical model included the fluid... in the flow area. The more flexible (5513 kPa) short-tube restricted the mass flow rate more than the most rigid (9889 kPa) short-tube used in this study. The mass flow rates estimated with the finite element model were as much as 14% higher than those from...
O'Neal, D.L.; Bassiouny, R.
Internal Stress in a Model Elasto-Plastic Fluid
Plastic materials can carry memory of past mechanical treatment in the form of internal stress. We introduce a natural definition of the vorticity of internal stress in a simple two-dimensional model of elasto-plastic fluids, which generates the internal stress. We demonstrate how the internal stress is induced under external loading, and how the presence of the internal stress modifies the plastic behavior.
Takeshi Ooshida; Ken Sekimoto
On the Doi Model for the suspensions of rod-like molecules in compressible fluids
On the Doi Model for the suspensions of rod-like molecules in compressible fluids Hantaek Bae and Konstantina Trivisa Key words: Doi model, suspensions of rod-like molecules, fluid-particle interaction model, compressible Navier-Stokes equations, Fokker-Planck-type equation. Abstract Polymeric fluids arise in many
Milchberg, Howard
Brinkmann Model and Double Penalization Method for the Flow Around a Porous Thin
the flow of a viscous fluid around a thin layer of porous material. Using a BKW method, we perform Keywords: Navier-Stokes equations, BKW method, penalization, porous ma- terial, thin layer. 1 Introduction are obtained with a BKW method. With these two asymptotic expansions, we will compare both models. We
Application of the ``Ke'' model to open channel flows in a magnetic field
,* , Mohamed Abdou a , Neil Morley a , Alice Ying a , Tomoaki Kunugi b a Mechanical and Aerospace Engineering-133 Engineering IV, Los Angeles, CA 90095-1597, USA b Department of Nuclear Engineering, Kyoto University, Japan-conductivity fluids such as molten salts. In the present study, the ``Ke'' model equations for turbulent flows
Abdou, Mohamed
Wind Turbine Modeling for Computational Fluid Dynamics: December 2010 - December 2012
With the shortage of fossil fuel and the increasing environmental awareness, wind energy is becoming more and more important. As the market for wind energy grows, wind turbines and wind farms are becoming larger. Current utility-scale turbines extend a significant distance into the atmospheric boundary layer. Therefore, the interaction between the atmospheric boundary layer and the turbines and their wakes needs to be better understood. The turbulent wakes of upstream turbines affect the flow field of the turbines behind them, decreasing power production and increasing mechanical loading. With a better understanding of this type of flow, wind farm developers could plan better-performing, less maintenance-intensive wind farms. Simulating this flow using computational fluid dynamics is one important way to gain a better understanding of wind farm flows. In this study, we compare the performance of actuator disc and actuator line models in producing wind turbine wakes and the wake-turbine interaction between multiple turbines. We also examine parameters that affect the performance of these models, such as grid resolution, the use of a tip-loss correction, and the way in which the turbine force is projected onto the flow field.
Tossas, L. A. M.; Leonardi, S.
A void distribution model-flashing flow
A new model for flashing flow based on wall nucleations is proposed here and the model predictions are compared with some experimental data. In order to calculate the bubble number density, the bubble number transport equation with a distributed source from the wall nucleation sites was used. Thus it was possible to avoid the usual assumption of a constant bubble number density. Comparisons of the model with the data shows that the model based on the nucleation site density correlation appears to be acceptable to describe the vapor generation in the flashing flow. For the limited data examined, the comparisons show rather satisfactory agreement without using a floating parameter to adjust the model. This result indicated that, at least for the experimental conditions considered here, the mechanistic predictions of the flashing phenomenon is possible on the present wall nucleation based model.
Riznic, J.; Ishii, M.; Afgan, N.
Multiparticle imaging technique for two-phase fluid flows using pulsed laser speckle velocimetry
The practical use of Pulsed Laser Velocimetry (PLV) requires the use of fast, reliable computer-based methods for tracking numerous particles suspended in a fluid flow. Two methods for performing tracking are presented. One method tracks a particle through multiple sequential images (minimum of four required) by prediction and verification of particle displacement and direction. The other method, requiring only two sequential images uses a dynamic, binary, spatial, cross-correlation technique. The algorithms are tested on computer-generated synthetic data and experimental data which was obtained with traditional PLV methods. This allowed error analysis and testing of the algorithms on real engineering flows. A novel method is proposed which eliminates tedious, undersirable, manual, operator assistance in removing erroneous vectors. This method uses an iterative process involving an interpolated field produced from the most reliable vectors. Methods are developed to allow fast analysis and presentation of sets of PLV image data. Experimental investigation of a two-phase, horizontal, stratified, flow regime was performed to determine the interface drag force, and correspondingly, the drag coefficient. A horizontal, stratified flow test facility using water and air was constructed to allow interface shear measurements with PLV techniques. The experimentally obtained local drag measurements were compared with theoretical results given by conventional interfacial drag theory. Close agreement was shown when local conditions near the interface were similar to space-averaged conditions. However, theory based on macroscopic, space-averaged flow behavior was shown to give incorrect results if the local gas velocity near the interface as unstable, transient, and dissimilar from the average gas velocity through the test facility.
Hassan, T.A.
Preliminary Analysis of Grande Ronde Basalt Formation Flow Top Transmissivity as it Relates to Assessment and Site Selection Applications for Fluid/Energy Storage and Sequestration Projects
Preliminary Analysis of Grande Ronde Basalt Formation Flow Top Transmissivity as it Relates to Assessment and Site Selection Applications for Fluid/Energy Storage and Sequestration Projects
Spane, Frank A.
Fracture Modeling and Flow Behavior in Shale Gas Reservoirs Using Discrete Fracture Networks
Fluid flow process in fractured reservoirs is controlled primarily by the connectivity of fractures. The presence of fractures in these reservoirs significantly affects the mechanism of fluid flow. They have led to problems in the reservoir which...
Ogbechie, Joachim Nwabunwanne
Friedmann-like collapsing model of a radiating sphere with heat flow
This paper considers a spherical body consisting of a fluid with heat flow which radiates in its exterior a null fluid described by the outgoing Vaidya's metric. A Friedmann-like exact solution of the interior Einstein field equations is given. It is proved that this solution, matched with the outgoing Vaidya matric, represents a physically reasonble collapsing model which, when the heat flow is switched off, reduces to the well-known collapsing model with dust. The proposed model has the remarkable property that even if the heat flow is small, the horizon will never be formed because, before this happens, the collapsing body will be destroyed by opposite gradients of pressure. 6 references.
Kolassis, C.A.; Santos, N.O.; Tsoubelis, D.
Green Algae as Model Organisms for Biological Fluid Dynamics
In the past decade the volvocine green algae, spanning from the unicellular $Chlamydomonas$ to multicellular $Volvox$, have emerged as model organisms for a number of problems in biological fluid dynamics. These include flagellar propulsion, nutrient uptake by swimming organisms, hydrodynamic interactions mediated by walls, collective dynamics and transport within suspensions of microswimmers, the mechanism of phototaxis, and the stochastic dynamics of flagellar synchronization. Green algae are well suited to the study of such problems because of their range of sizes (from 10 $\\mu$m to several millimetres), their geometric regularity, the ease with which they can be cultured and the availability of many mutants that allow for connections between molecular details and organism-level behavior. This review summarizes these recent developments and highlights promising future directions in the study of biological fluid dynamics, especially in the context of evolutionary biology, that can take advantage of these re...
Goldstein, Raymond E
In the past decade the volvocine green algae, spanning from the unicellular $Chlamydomonas$ to multicellular $Volvox$, have emerged as model organisms for a number of problems in biological fluid dynamics. These include flagellar propulsion, nutrient uptake by swimming organisms, hydrodynamic interactions mediated by walls, collective dynamics and transport within suspensions of microswimmers, the mechanism of phototaxis, and the stochastic dynamics of flagellar synchronization. Green algae are well suited to the study of such problems because of their range of sizes (from 10 $\\mu$m to several millimetres), their geometric regularity, the ease with which they can be cultured and the availability of many mutants that allow for connections between molecular details and organism-level behavior. This review summarizes these recent developments and highlights promising future directions in the study of biological fluid dynamics, especially in the context of evolutionary biology, that can take advantage of these remarkable organisms.
Raymond E. Goldstein
The purpose of the saturated zone (SZ) flow and transport model abstraction task is to provide radionuclide-transport simulation results for use in the total system performance assessment (TSPA) for license application (LA) calculations. This task includes assessment of uncertainty in parameters that pertain to both groundwater flow and radionuclide transport in the models used for this purpose. This model report documents the following: (1) The SZ transport abstraction model, which consists of a set of radionuclide breakthrough curves at the accessible environment for use in the TSPA-LA simulations of radionuclide releases into the biosphere. These radionuclide breakthrough curves contain information on radionuclide-transport times through the SZ. (2) The SZ one-dimensional (I-D) transport model, which is incorporated in the TSPA-LA model to simulate the transport, decay, and ingrowth of radionuclide decay chains in the SZ. (3) The analysis of uncertainty in groundwater-flow and radionuclide-transport input parameters for the SZ transport abstraction model and the SZ 1-D transport model. (4) The analysis of the background concentration of alpha-emitting species in the groundwater of the SZ.
Lattice Versus Lennard-Jones Models with a Net Particle Flow
. Such phenomenol- ogy occurs in flowing fluids [3], and during phase separation in colloidal [4], granular [5, 6
Garrido, Pedro L.
FLUID DISPLACEMENT IN PETROLEUM RESERVOIRS C. Anderson andFLUID DISPLACEMENT IN PETROLEUM RESERVOIRS C. Anderson andachieve optimal recovery of petroleum from a reservoir, it
Anderson, C.
Virtual Community Life Cycle: a Model to Develop Systems with Fluid Requirements Christo El Morr1
1 Virtual Community Life Cycle: a Model to Develop Systems with Fluid Requirements Christo El Morr1 into the life cycle model needed to develop information systems for group of people with fluid requirements development life cycles can be followed when developing any virtual community. Though, in a fluid environment
Multi-fluid Modeling of Transient a Case Study in the Generation and Guiding of Light
Multi-fluid Modeling of Transient Plasmas: a Case Study in the Generation and Guiding of Light, B.H.P. Multi-fluid Modeling of Transient Plasmas: a Case Study in the Generation and Guid- ing . . . . . . . . . . . . . . . . . . . . . . . . 37 2.3.1 The multi-fluid description in PLASIMO . . . . . . . . . . . . . . . . 38 iii #12;iv
Eindhoven, Technische Universiteit
On models for viscoelastic fluid-like materials that are mechanically incompressible and
On models for viscoelastic fluid-like materials that are mechanically incompressible and thermally of the full NavierStokesFourier system. J. Math. Fluid Mech., 11:274302, 2009 Mechanically incompressible;Viscoelastic fluids Maxwell model F l lsld µm m Mechanical analogue: Spring energy storage. Dashpot
Cerveny, Vlastislav
Model energy landscapes of low-temperature fluids: Dipolar hard spheres Dmitry V. Matyushov*
Model energy landscapes of low-temperature fluids: Dipolar hard spheres Dmitry V. Matyushov* Center January 2007; revised manuscript received 5 March 2007; published 24 July 2007 An analytical model of non-Gaussian energy landscape of low-temperature fluids is developed based on the thermodynamics of the fluid
Matyushov, Dmitry
Efficient Production Optimization Using Flow Network Models
of the physical processes that govern the long-term behavior of the reservoir. We present an alternative solution that combines the advantages of both statistics-based and physics-based methods by deriving the flow predictions in complex two-dimensional models...
Lerlertpakdee, Pongsathorn
approaches pursued were based on using : (i) linear or nonlinear Shallow Water Wave equations (Carrier approaches. Griffiths et al. 28 1992, compared measurements of internal kinematics of periodic waves shoalingCHAPTER NO. FULLY NONLINEAR POTENTIAL FLOW MODELS USED FOR LONG WAVE RUNUP PREDICTION (S. Grilli
Grilli, Stéphan T.
An Anisotropic Fluid-Solid Model of the Mouse Heart
A critical challenge in biomechanical simulations is the spatial discretization of complex fluid-solid geometries created from imaging. This is especially important when dealing with Lagrangian interfaces, as there must be at a minimum both geometric and topological compatibility between fluid and solid phases, with exact matching of the interfacial nodes being highly desirable. We have developed a solution to this problem and applied the approach to the creation of a 3D fluidsolid mesh of the mouse heart. First, a 50 micron isotropic MRI dataset of a perfusion-fixed mouse heart was segmented into blood, tissue, and background using a customized multimaterial connected fuzzy thresholding algorithm. Then, a multimaterial marching cubes algorithm was applied to produce two compatible isosurfaces, one for the blood-tissue boundary and one for the tissue-background boundary. A multimaterial smoothing algorithm that rigorously conserves volume for each phase simultaneously smoothed the isosurfaces. Next we applied novel automated meshing algorithms to generate anisotropic hybrid meshes with the number of layers and the desired element anisotropy for each material as the only input parameters. As the meshes are scale-invariant within a material and include boundary layer prisms, fluid-structure interaction computations would have a relative error equilibrated over the entire mesh. The resulting model is highly detailed mesh representation of the mouse heart, including features such as chordae and coronary vasculature, that is also maximally efficient to produce the best simulation results for the computational resources available
Carson, James P.; Kuprat, Andrew P.; Jiao, Xiangmin; del Pin, Facundo; Einstein, Daniel R.
Fluid flow near reservoir lakes inferred from the spatial and temporal analysis of the electric potential
, 2002. 1. Introduction [2] Detecting subsurface groundwater circulation using geophysical methods to result from the electrokinetic coupling associated with a vertical groundwater flow connecting a constant pore pressure source to the bottom of the lakes. Numerical modeling indicates that the spatial
Adolphs, Ralph
Three-dimensional Computational Fluid Dynamics (CFD) modeling of dry spent nuclear fuel storage canisters
One of the interim storage configurations being considered for aluminum-clad foreign research reactor fuel, such as the Material and Testing Reactor (MTR) design, is in a dry storage facility. To support design studies of storage options, a computational and experimental program was conducted at the Savannah River Site (SRS). The objective was to develop computational fluid dynamics (CFD) models which would be benchmarked using data obtained from a full scale heat transfer experiment conducted in the SRS Experimental Thermal Fluids Laboratory. The current work documents the CFD approach and presents comparison of results with experimental data. CFDS-FLOW3D (version 3.3) CFD code has been used to model the 3-dimensional convective velocity and temperature distributions within a single dry storage canister of MTR fuel elements. For the present analysis, the Boussinesq approximation was used for the consideration of buoyancy-driven natural convection. Comparison of the CFD code can be used to predict reasonably accurate flow and thermal behavior of a typical foreign research reactor fuel stored in a dry storage facility.
Lee, S.Y.
Thermodynamic Micellization Model of Asphaltene Precipitation from Petroleum Fluids
of diverse chemical nature consti- tute petroleum fluids. These include paraffinic, naphthenic, and aromatic
Firoozabadi, Abbas
A bulk-flow model of angled injection Lomakin bearings
A bulk-flow model for determination of the leakage and dynamic force characteristics of angled injection Lomakin bearings is presented. Zeroth- and first-order equations describe the equilibrium flow for a centered bearing and the perturbed flow...
Soulas, Thomas Antoine Theo
Unit physics performance of a mix model in Eulerian fluid computations
In this report, we evaluate the performance of a K-L drag-buoyancy mix model, described in a reference study by Dimonte-Tipton [1] hereafter denoted as [D-T]. The model was implemented in an Eulerian multi-material AMR code, and the results are discussed here for a series of unit physics tests. The tests were chosen to calibrate the model coefficients against empirical data, principally from RT (Rayleigh-Taylor) and RM (Richtmyer-Meshkov) experiments, and the present results are compared to experiments and to results reported in [D-T]. Results show the Eulerian implementation of the mix model agrees well with expectations for test problems in which there is no convective flow of the mass averaged fluid, i.e., in RT mix or in the decay of homogeneous isotropic turbulence (HIT). In RM shock-driven mix, the mix layer moves through the Eulerian computational grid, and there are differences with the previous results computed in a Lagrange frame [D-T]. The differences are attributed to the mass averaged fluid motion and examined in detail. Shock and re-shock mix are not well matched simultaneously. Results are also presented and discussed regarding model sensitivity to coefficient values and to initial conditions (IC), grid convergence, and the generation of atomically mixed volume fractions.
Vold, Erik [Los Alamos National Laboratory; Douglass, Rod [Los Alamos National Laboratory
Gamma-ray free-electron lasers: Quantum fluid model
A quantum fluid model is used to describe the interacion of a nondegenerate cold relativistic electron beam with an intense optical wiggler taking into account the beam space-charge potential and photon recoil effect. A nonlinear set of coupled equations are obtained and solved numerically. The numerical results shows that in the limit of plasma wave-breaking an ultra-high power radiation pulse are emitted at the$\\gamma$-ray wavelength range which can reach an output intensity near the Schwinger limit depending of the values of the FEL parameters such as detuning and input signal initial phase at the entrance of the interaction region.
Silva, H M
Determination of fluid viscosities from biconical annular geometries: Experimental and modeling studies
Knowledge of viscosity of flow streams is essential for the design and operation of production facilities, drilling operations and reservoir engineering calculations. The determination of the viscosity of a reservoir fluid at downhole conditions...
Rondon, Nolys Javier
Method and apparatus for balancing discharge fluid flow in drilling mud treatment units
A method of controlling fluid flow in the drilling mud treatment units of an oil/gas well drilling rig such as, for example, the shale shaker, desander, desilter, and mud cleaner portions thereof provides floating the inlet of an intake conduit at the supernatent liquid layer of the drilling rig reserve pit and providing a common distributor head for routing the supernatent liquid to the various solid control units. A pump is connected to the intake conduit and the header at the intake and discharge respectively. The pump transmits the reserve pit supernatent from the reserve pit to the header by pumping. There is provided one or more branch lines affixed to the header each discharging respectively into the drain of a drilling mud treatment unit associated with the drilling rig with the flow of reserve pit supernatent liquid keeping the various drains open. The drains are positioned to discharge back into the reserve pit. The method saves the use of fresh water for the purpose of keeping drains open by the use of the supernatent liquid.
Gay, C.J.
Magnetic fabrics and fluid flow directions in hydrothermal systems. A case study in the Chaillac BaFFe deposits
of anisotropy of magnetic susceptibility (AMS) to describe the mineralizing process in hydrothermal systems. BaMagnetic fabrics and fluid flow directions in hydrothermal systems. A case study in the Chaillac Ba hydrothermal textures and tectonic structures have been described in veins, sinters, and sandstone cemented
Nested Cartesian grid method in incompressible viscous fluid flow Yih-Ferng Peng a,*, Rajat Mittal b
Nested Cartesian grid method in incompressible viscous fluid flow Yih-Ferng Peng a,*, Rajat Mittal form 16 April 2010 Accepted 28 May 2010 Available online 8 June 2010 Keywords: Nested Cartesian grid procedure is focused by using a nested Cartesian grid formulation. The method is developed for simulating
Mittal, Rajat
Membrane filtration studies of inversely soluble model metalworking fluids
Model metalworking fluids, characterized by phase separation of functional components at elevated temperatures, were studied. Results of membrane filtration experiments with three oils of differing chemical nature confirm the feasibility of specific removal of finely dispersed contaminant oils without the simultaneous loss of active components from adequately formulated fluids. Prerequisites are that membrane materials and pore sizes be suitably chosen and that operating temperatures be kept below the cloud point of the least soluble component. The most suitable filter in the present study was a hydrophilic regenerated cellulose membrane with a NMWL of 100,000 dalton. Complete oil removal was attained if membrane pore sizes did not exceed 0.1 {micro}m. It was also found that intrinsically water-soluble boundary lubricants of the polyglycol ether type are retained by membranes in the presence of PPG-1800, which serves as a precipitation promoter above the cloud point. This is of considerable practical importance since it offers the possibility of designing water-soluble boundary lubrication and extreme pressure additives which are activated by the presence of an inversely soluble component above its cloud point. The latter compound also acts as the principal hydrodynamic lubricant of the present model formulations. The usefulness of a new analytical tool for the rapid acquisition and imaging of data pertinent to changes in molecular aggregation and phase conditions was demonstrated.
Misra, S.K.; Skoeld, R.O. [Chalmers Univ. of Technology, Gothenburg (Sweden)] [Chalmers Univ. of Technology, Gothenburg (Sweden)
A survey of air flow models for multizone structures
Air flow models are used to simulate the rates of incoming and outgoing air flows for a building with known leakage under given weather and shielding conditions. Additional information about the flow paths and air-mass flows inside the building can only by using multizone air flow models. In order to obtain more information on multizone air flow models, a literature review was performed in 1984. A second literature review and a questionnaire survey performed in 1989, revealed the existence of 50 multizone air flow models, all developed since 1966, two of which are still under development. All these programs use similar flow equations for crack flow but differ in the versatility to describe the full range of flow phenomena and the algorithm provided for solving the set of nonlinear equations. This literature review was found that newer models are able to describe and simulate the ventilation systems and interrelation of mechanical and natural ventilation. 27 refs., 2 figs., 1 tab.
Feustel, H.E.; Dieris, J.
Force-free swimming of a model helical flagellum in viscoelastic fluids
Force-free swimming of a model helical flagellum in viscoelastic fluids Bin Liua,1 , Thomas R. Powersa,b , and Kenneth S. Breuera a School of Engineering, Box D, Brown University, Providence, RI 02912 fluids. The fluids are highly viscous to replicate the low Reynolds number environment of microorgan
Thomases, Becca
Identification of fluid-flow paths in the Cerro Prieto geothermal field
A hydrogeologic model of the Cerro Prieto geothermal field has been developed based on geophysical and lithologic well logs, downhole temperature, and well completion data from about 90 deep wells. The hot brines seem to originate in the eastern part of the field, flowing in a westward direction and rising through gaps in the shaly layers which otherwise act as partial caprocks to the geothermal resource.
Halfman, S.E.; Lippmann, M.J.; Zelwer, R.; Howard, J.H.
A modeling approach for analysis of coupled multiphase fluid flow ...
tion of hazardous waste, geothermal energy extraction, ... and soil mechanics and can also handle coupled ... flux density for energy over all phases (J/(m2 s)).
Monitoring and Modeling Fluid Flow in a Developing Enhanced Geothermal...
Salak geothermal field in Indonesia. The ultimate goal is to characterize subsurface fracture system and reservoir permeability (possibly, their temporal evolution) using...
Seismicity; 2010 Geothermal Technology Program Peer Review Report Seismic Fracture Characterization Methods for Enhanced Geothermal Systems; 2010 Geothermal Technology...
Monitoring and Modeling Fluid Flow in a Developing EGS
field to better understand stress changes and permeability development during the fracture growth stage of an EGS development Question Why does seismicity appear to be...
Numerical modeling of fluid flow and time-lapse seismograms ...
which is mainly discharged into the atmosphere, increasing the atmosphere temperature. (greenhouse effect). � To minimize climate change impacts, geological.
Abstract. CO2 sequestration in the underground is a valid alternative approach for mitigat- ing the greenhouse effect. Nevertheless, very little is known about the
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc DocumentationP-Series to someone6Energy,MUSEUM DISPLAY STATUS4Tours SHARE Tours PublicCan We
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc DocumentationP-Series to someone6Energy,MUSEUM DISPLAY STATUS4Tours SHARE Tours PublicCan WeCan
A Mixed Finite Element Framework for Modeling Coupled Fluid Flow ...
such as recovery from compaction drive, waterflooding, surface subsidence, seal in- tegrity ...... and for rocks and concrete it is in the range of 0.4-0.6. ...... incorporate into the programs an automatic, self-adaptive, procedure which adjusts.
Birendra Jha
Imaging, Characterizing, and Modeling of Fracture Networks and Fluid Flow
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:YearRound-UpHeatMulti-Dimensionalthe U.S. Department-2023 Idaho4 AUDIT REPORTIlluminatedin EGS
Turbulent Flow and Transport Modeling by Long Waves and Currents
This dissertation presents models for turbulent flow and transport by currents and long waves in large domain. From the Navier-Stokes equations, a fully nonlinear depth-integrated equation model for weakly dispersive, turbulent and rotational flow...
Kim, Dae Hong
Numerical modeling of the elution peak profiles of retained solutes in supercritical fluid chromatography
In supercritical fluid chromatography (SFC), the significant expansion of the mobile phase along the column causes the formation of axial and radial gradients of temperature. Due to these gradients, the mobile phase density, its viscosity, its velocity, its diffusion coefficients, etc. are not constant throughout the column. This results in a nonuniform flow velocity distribution, itself causing a loss of column efficiency in certain cases, even at low flow rates, as they do in HPLC. At high flow rates, an important deformation of the elution profiles of the sample components may occur. The model previously used to account satisfactorily for the retention of an unsorbed solute in SFC is applied to the modeling of the elution peak profiles of retained compounds. The numerical solution of the combined heat and mass balance equations provides the temperature and the pressure profiles inside the column and values of the retention time and the band profiles of retained compounds that are in excellent agreement with independent experimental data for large value of mobile phase reduced density. At low reduced densities, the band profiles can strongly depend on the column axial distribution of porosity.
Kaczmarski, Krzysztof [University of Tennessee and Rzeszow University of Technology, Poland; Guiochon, Georges A [ORNL
The accuracy of numerical predictions for gas/liquid two-phase flows using Computational Multiphase Fluid Dynamics (CMFD) methods strongly depends on the formulation of models governing the interaction between the continuous liquid field and bubbles of different sizes. The purpose of this paper is to develop, test and validate a multifield model of adiabatic gas/liquid flows at intermediate gas concentrations (e.g., churn-turbulent flow regime), in which multiple-size bubbles are divided into a specified number of groups, each representing a prescribed range of sizes. The proposed modeling concept uses transport equations for the continuous liquid field and for each bubble field. The overall model has been implemented in the NPHASE-CMFD computer code. The results of NPHASE-CMFD simulations have been validated against the experimental data from the TOPFLOW test facility. Also, a parametric analysis on the effect of various modeling assumptions has been performed.
Elena A. Tselishcheva; Steven P. Antal; Michael Z. Podowski; Donna Post Guillen
Computational Fluid Dynamics Modeling of the John Day Dam Tailrace
US Army Corps of Engineers - Portland District required that a two-dimensional (2D) depth-averaged and a three-dimensional (3D) free-surface numerical models to be developed and validated for the John Day tailrace. These models were used to assess potential impact of a select group of structural and operational alternatives to tailrace flows aimed at improving fish survival at John Day Dam. The 2D model was used for the initial assessment of the alternatives in conjunction with a reduced-scale physical model of the John Day Project. A finer resolution 3D model was used to more accurately model the details of flow in the stilling basin and near-project tailrace hydraulics. Three-dimensional model results were used as input to the Pacific Northwest National Laboratory particle tracking software, and particle paths and times to pass a downstream cross section were used to assess the relative differences in travel times resulting from project operations and structural scenarios for multiple total river flows. Streamlines and neutrally-buoyant particles were seeded in all turbine and spill bays with flows. For a Total River of 250 kcfs running with the Fish Passage Plan spill pattern and a spillwall, the mean residence times for all particles were little changed; however the tails of the distribution were truncated for both spillway and powerhouse release points, and, for the powerhouse releases, reduced the residence time for 75% of the particles to pass a downstream cross section from 45.5 minutes to 41.3 minutes. For a total river of 125 kcfs configured with the operations from the Fish Passage Plan for the temporary spillway weirs and for a proposed spillwall, the neutrally-buoyant particle tracking data showed that the river with a spillwall in place had the overall mean residence time increase; however, the residence time for 75% of the powerhouse-released particles to pass a downstream cross section was reduced from 102.4 min to 89 minutes.
Rakowski, Cynthia L.; Perkins, William A.; Richmond, Marshall C.; Serkowski, John A.
A Lattice Boltzmann Fictitious Domain Method for Modeling Red Blood Cell Deformation and Multiple-Cell Hydrodynamic Interactions in Flow
To model red blood cell (RBC) deformation in flow, the recently developed LBM-DLM/FD method ([Shi and Lim, 2007)29], derived from the lattice Boltzmann method and the distributed Lagrange multiplier/fictitious domain methodthe fictitious domain method, is extended to employ the mesoscopic network model for simulations of red blood cell deformation. The flow is simulated by the lattice Boltzmann method with an external force, while the network model is used for modeling red blood cell deformation and the fluid-RBC interaction is enforced by the Lagrange multiplier. To validate parameters of the RBC network model, sThe stretching numerical tests on both coarse and fine meshes are performed and compared with the corresponding experimental data to validate the parameters of the RBC network model. In addition, RBC deformation in pipe flow and in shear flow is simulated, revealing the capacity of the current method for modeling RBC deformation in various flows.
Shi, Xing; Lin, Guang; Zou, Jianfeng; Fedosov, Dmitry A.
Traffic flow models and service rules for complex production systems
Traffic flow models and service rules for complex production systems C. Ringhofer Abstract We emphasis is given to the implementation of service rules for complex systems, involving multiple product flow type models for complex production systems. Traffic flow models represent, in some sense
Ringhofer, Christian
MECH 502: Fluid Mechanics Winter semester 2010
MECH 502: Fluid Mechanics Winter semester 2010 Instructor: I.A. Frigaard Times: Tuesdays week of semester. Location: CHBE 103 Synopsis: This course will focus primarily on fluid mechanics will be to look at fluid mechanics fundamentals, and at the mathematical modeling & analysis of simplified flow
Application of Multi-rate Flowing Fluid Electric ConductivityLogging Method to Well DH-2, Tono Site, Japan
The flowing fluid electric conductivity (FEC) logging method, wellbore fluid is replaced with de-ionized water, following which FEC profiles in the wellbore are measured at a series of times while the well is pumped at a constant rate. Locations were fluid enters the wellbore show peaks in the FEC logs, which may be analyzed to infer inflow strengths and salinities of permeable features intersected by the wellbore. In multi-rate flowing FEC logging, the flowing FEC logging method is repeated using two or more pumping rates, which enables the transmissivities and inherent pressure heads of these features to be estimated as well. We perform multi-rate FEC logging on a deep borehole in fractured granitic rock, using three different pumping rates. Results identify 19 hydraulically conducting fractures and indicate that transmissivity, pressure head, and salinity vary significantly among them. By using three pumping rates rather than the minimum number of two, we obtain an internal consistency check on the analysis that provides a measure of the uncertainty of the results. Good comparisons against static FEC profiles and against independent chemical, geological, and hydrogeological data have further enhanced confidence in the results of the multi-rate flowing FEC logging method.
Doughty, Christine; Takeuchi, Shinji; Amano, Kenji; Shimo, Michito; Tsang, Chin-Fu
Flow in Central High Energy Nuclear Collisions H. Stockera,theoretical models of high energy nuclear collisions andunder Contract High energy nuclear collisions offer a unique
Stocker, H.
Baroclinic flow and the Lorenz-84 model
The bifurcation diagram of a truncation to six degrees of freedom of the equations for quasi-geostrophic, baroclinic flow is investigated. Period doubling cascades and Shil'nikov bifurcations lead to chaos in this model. The low dimension of the chaotic attractor suggests the possibility to reduce the model to three degrees of freedom. In a physically comprehensible limit of the parameters this reduction is done explicitly. The bifurcation diagram of the reduced model in this limit is compared to the diagram of the six degrees of freedom model and agrees well. A numerical implementation of the graph transform is used to approximate the three dimensional invariant manifold away from the limit case. If the six dimensional model is reduced to a linearisation of the invariant manifold about the Hadley state, the Lorenz-84 model is found. Its parameters can then be calculated from the physical parameters of the quasi-geostrophic model. Bifurcation diagrams at physical and traditional parameter values are compared and routes to chaos in the Lorenz-84 model are described.
Lennaert van Veen
Physical Model Development and Benchmarking for MHD Flows in Blanket Design
An advanced simulation environment to model incompressible MHD flows relevant to blanket conditions in fusion reactors has been developed at HyPerComp in research collaboration with TEXCEL. The goals of this phase-II project are two-fold: The first is the incorporation of crucial physical phenomena such as induced magnetic field modeling, and extending the capabilities beyond fluid flow prediction to model heat transfer with natural convection and mass transfer including tritium transport and permeation. The second is the design of a sequence of benchmark tests to establish code competence for several classes of physical phenomena in isolation as well as in select (termed here as �canonical�,) combinations. No previous attempts to develop such a comprehensive MHD modeling capability exist in the literature, and this study represents essentially uncharted territory. During the course of this Phase-II project, a significant breakthrough was achieved in modeling liquid metal flows at high Hartmann numbers. We developed a unique mathematical technique to accurately compute the fluid flow in complex geometries at extremely high Hartmann numbers (10,000 and greater), thus extending the state of the art of liquid metal MHD modeling relevant to fusion reactors at the present time. These developments have been published in noted international journals. A sequence of theoretical and experimental results was used to verify and validate the results obtained. The code was applied to a complete DCLL module simulation study with promising results.
Ramakanth Munipalli; P.-Y.Huang; C.Chandler; C.Rowell; M.-J.Ni; N.Morley; S.Smolentsev; M.Abdou
Observing and modeling Earths energy flows
This article reviews, from the authors perspective, progress in observing and modeling energy flows in Earth's climate system. Emphasis is placed on the state of understanding of Earth's energy flows and their susceptibility to perturbations, with particular emphasis on the roles of clouds and aerosols. More accurate measurements of the total solar irradiance and the rate of change of ocean enthalpy help constrain individual components of the energy budget at the top of the atmosphere to within {+-}2 W m{sup -2}. The measurements demonstrate that Earth reflects substantially less solar radiation and emits more terrestrial radiation than was believed even a decade ago. Active remote sensing is helping to constrain the surface energy budget, but new estimates of downwelling surface irradiance that benefit from such methods are proving difficult to reconcile with existing precipitation climatologies. Overall, the energy budget at the surface is much more uncertain than at the top of the atmosphere. A decade of high-precision measurements of the energy budget at the top of the atmosphere is providing new opportunities to track Earth's energy flows on timescales ranging from days to years, and at very high spatial resolution. The measurements show that the principal limitation in the estimate of secular trends now lies in the natural variability of the Earth system itself. The forcing-feedback-response framework, which has developed to understand how changes in Earth's energy flows affect surface temperature, is reviewed in light of recent work that shows fast responses (adjustments) of the system are central to the definition of the effective forcing that results from a change in atmospheric composition. In many cases, the adjustment, rather than the characterization of the compositional perturbation (associated, for instance, with changing greenhouse gas concentrations, or aerosol burdens), limits accurate determination of the radiative forcing. Changes in clouds contribute importantly to this adjustment and thus contribute both to uncertainty in estimates of radiative forcing and to uncertainty in the response. Models are indispensable to calculation of the adjustment of the system to a compositional change but are known to be flawed in their representation of clouds. Advances in tracking Earth's energy flows and compositional changes on daily through decadal timescales are shown to provide both a critical and constructive framework for advancing model development and evaluation.
Stevens B.; Schwartz S.
Elliptic Flow from a Hybrid CGC, Full 3D Hydro and Hadronic Cascade Model
We investigate the robustness of the discovery of the perfect fluid through comparison of hydrodynamic calculations with the elliptic flow coefficient v_2 at midrapidity in Au+Au collisions at sqrt{s_{NN}}=200 GeV. Employing the Glauber model for initial entropy density distributions, the centrality dependence of v_2 is reasonably reproduced by using an ideal fluid description of the early QGP stage followed by a hadronic cascade in the late hadronic stage. On the other hand, initial conditions based on the Colour Glass Condensate model are found to generate larger elliptic flow due to larger initial eccentricity epsilon. We further predict v_2/epsilon at a fixed impact parameter as a function of collision energy sqrt{s_{NN}} up to the LHC energy.
Tetsufumi Hirano; Ulrich W. Heinz; Dmitri Kharzeev; Roy Lacey; Yasushi Nara
Flow characteristics in an irregular spillway model
River Authority. TABLE OF CONTENTS Page ACKNOWLEDGEMENT TABLE OF CONTENTS V1 LIST OF FIGURES LIST OF TABLES INTRODUCTION REVIEW OF LITERATURE Open Channel Flow Spillways Physical Modeling METHODS AND PROCEDURES 5 5 10 16 20 RESULTS... Test Test Test Test Test Test Test Test Test Test Test Test Test Test Test Test 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 ? PMF Test 27 27 29 29 32 35 38 43 43 49 49 52 56 63 63 65 65 DISCUSSION S...
Scott, Mary Charlene
Development of enhanced geothermal systems (EGS) will require creation of a reservoir of sufficient volume to enable commercial-scale heat transfer from the reservoir rocks to the working fluid. A key assumption associated with reservoir creation/stimulation is that sufficient rock volumes can be hydraulically fractured via both tensile and shear failure, and more importantly by reactivation of naturally existing fractures (by shearing), to create the reservoir. The advancement of EGS greatly depends on our understanding of the dynamics of the intimately coupled rock-fracture-fluid-heat system and our ability to reliably predict how reservoirs behave under stimulation and production. Reliable performance predictions of EGS reservoirs require accurate and robust modeling for strongly coupled thermal-hydrological-mechanical (THM) processes. Conventionally, these types of problems have been solved using operator-splitting methods, usually by coupling a subsurface flow and heat transport simulators with a solid mechanics simulator via input files. An alternative approach is to solve the system of nonlinear partial differential equations that govern multiphase fluid flow, heat transport, and rock mechanics simultaneously, using a fully coupled, fully implicit solution procedure, in which all solution variables (pressure, enthalpy, and rock displacement fields) are solved simultaneously. This paper describes numerical simulations used to investigate the poro- and thermal- elastic effects of working fluid injection and thermal energy extraction on the properties of the fractures and rock matrix of a hypothetical EGS reservoir, using a novel simulation software FALCON (Podgorney et al., 2011), a finite element based simulator solving fully coupled multiphase fluid flow, heat transport, rock deformation, and fracturing using a global implicit approach. Investigations are also conducted on how these poro- and thermal-elastic effects are related to fracture permeability evolution.
Robert Podgorney; Chuan Lu; Hai Huang
Investigation of Volume of Fluids (VOF) Method and System Models for Design of Microfluidic Ink Delivery Apparatus for Dip Pen Nanolithography (DPN)
Investigation of Volume of Fluids (VOF) Method and System Models for Design of Microfluidic Ink and manufacture of commercial microfluidic systems called "InkwellsTM". In this study VOF method was used sequence of flow in the different parts of the microfluidic network. Keywords: lab-on-chip, micro
Banerjee, Debjyoti
Fully Coupled Well Models for Fluid Injection and Production...
Wells provide a conduit for injecting greenhouse gases and producing reservoirs fluids, such as brines, natural gas, and crude oil, depending on the target reservoir. Well...
Potential Flow Modelling for Wind Turbines Shane Cline
Potential Flow Modelling for Wind Turbines by Shane Cline B.Sc., University of Toledo, 2003 M means, without the permission of the author. #12;ii Potential Flow Modelling for Wind Turbines by Shane potential flow methods are a promising alternative to mainstream wind turbine aerodynamics tools
Victoria, University of
Forebay Computational Fluid Dynamics Modeling for The Dalles Dam to Support Vortex Suppress Device Studies
A computational fluid dynamics (CFD) model was used in an investigation into the suppression of a surface vortex that forms and the south-most spilling bay at The Dalles Project. The CFD work complemented work at the prototype and the reduced-scale physical models. The CFD model was based on a model developed for other work in the forebay but had additional resolution added near the spillway. Vortex suppression devices (VSDs) were to placed between pier noses and/or in the bulkhead slot of the spillway bays. The simulations in this study showed that placing VSD structures or a combination of structures to suppress the vortex would still result in near-surface flows to be entrained in a vortex near the downstream spillwall. These results were supported by physical model and prototype studies. However, there was a consensus of the fish biologists at the physical model that the fish would most likely move north and if the fish went under the VSD it would immediately exit the forebay through the tainter gate and not get trapped between VSDs or the VSDs and the tainter gate if the VSDs were deep enough.
Rakowski, Cynthia L.; Richmond, Marshall C.; Serkowski, John A.
Stochastic and deterministic models for dense granular flow
Granular materials such as sand or gravel surround us everyday and yet remain poorly understood. In this thesis, two models are developed for dense granular flow, each capable of predicting flows with accuracy in multiple ...
Kamrin, Kenneth Norman
Hamiltonian structure of reduced fluid models for plasmas obtained from a kinetic description
We consider the Hamiltonian structure of reduced fluid models obtained from a kinetic description of collisionless plasmas by Vlasov-Maxwell equations. We investigate the possibility of finding Poisson subalgebras associated with fluid models starting from the Vlasov-Maxwell Poisson algebra. In this way, we show that the only possible Poisson subalgebra involves the moments of zeroth and first order of the Vlasov distribution, meaning the fluid density and the fluid velocity. We find that the bracket derived in [Phys. Rev. Lett. 93, 175002 (2004)] which involves moments of order 2 is not a Poisson bracket since it does not satisfy the Jacobi identity.
Lo�c De Guillebon; Cristel Chandre
Statistical Estimation of Fluid Flow Fields Johnny Chang David Edwards Yizhou Yu
their motion fields. 1 Introduction Dynamic fluids, such as rivers, ocean waves, moving clouds, smoke and fires (4) where is the kinematic viscosity of the fluid, is its den- sity and f is an external force scale. A good ex- ample is the changing surface geometry of a water surface. This is because the self
Yu, Yizhou
One-dimensional fluid diffusion induced by constant-rate flow injection: Theoretical analysis and application
is essential in the exploitation of natural fluid resources, such as water, steam, petroleum, and natural gas advantages of our method are the reliability of the testing method, its economy of time, and the flexibility wastes. [3] In general, the nature of fluids in reservoir rocks can be characterized in terms of quantity
Application of X-ray CT for investigating fluid flow and conformance control during CO2 injection in highly heterogeneous media
were performed using homogeneous and heterogeneous cores and a 4th generation X-Ray CT scanner was used to visualize heterogeneity and fluid flow in the core. Porosity and saturation measurements were made during the course of the experiment...
Chakravarthy, Deepak
Swirling structure for mixing two concentric fluid flows at nozzle outlet
A nozzle device is described for causing two fluids to mix together. In particular, a spray nozzle comprises two hollow, concentric housings, an inner housing and an outer housing. The inner housing has a channel formed therethrough for a first fluid. Its outer surface cooperates with the interior surface of the outer housing to define the second channel for a second fluid. The outer surface of the inner housing and the inner surface of the outer housing each carry a plurality of vanes that interleave but do not touch, each vane of one housing being between two vanes of the other housing. The vanes are curved and the inner surface of the outer housing and the outer surface of the inner housing converge to narrow the second channel. The shape of second channel results in a swirling, accelerating second fluid that will impact the first fluid just past the end of the nozzle where mixing will take place.
Mensink, D.L.
Determination of several variables affecting laboratory measurements of cross-linked fracture fluids
SHEAR RATE o) PSEUDOPLASTIC NEWTONIAN SHEAR RATE b) Figure 3 ? Fluid Flow Behavior shear rate. These fluids are also called shear-thinning fluids. The power law (Ostwald-dewaele) model is the most popular model used to describe the flow behavior...
Wilson, Matilda Jane
Unbounded dynamics in dissipative flows: R�ssler model
Transient chaos and unbounded dynamics are two outstanding phenomena that dominate in chaotic systems with large regions of positive and negative divergences. Here, we investigate the mechanism that leads the unbounded dynamics to be the dominant behavior in a dissipative flow. We describe in detail the particular case of boundary crisis related to the generation of unbounded dynamics. The mechanism of the creation of this crisis in flows is related to the existence of an unstable focus-node (or a saddle-focus) equilibrium point and the crossing of a chaotic invariant set of the system with the weak-(un)stable manifold of the equilibrium point. This behavior is illustrated in the well-known R�ssler model. The numerical analysis of the system combines different techniques as chaos indicators, the numerical computation of the bounded regions, and bifurcation analysis. For large values of the parameters, the system is studied by means of Fenichel's theory, providing formulas for computing the slow manifold which influences the evolution of the first stages of the orbit.
Barrio, Roberto, E-mail: firstname.lastname@example.com; Serrano, Sergio, E-mail: email@example.com [Computational Dynamics Group, Dpto. Matem�tica Aplicada and IUMA, Universidad de Zaragoza, E-50009 Zaragoza (Spain)] [Computational Dynamics Group, Dpto. Matem�tica Aplicada and IUMA, Universidad de Zaragoza, E-50009 Zaragoza (Spain); Blesa, Fernando, E-mail: firstname.lastname@example.com [Computational Dynamics Group, Dpto. F�sica Aplicada and IUMA, Universidad de Zaragoza, E-50009 Zaragoza (Spain)] [Computational Dynamics Group, Dpto. F�sica Aplicada and IUMA, Universidad de Zaragoza, E-50009 Zaragoza (Spain)
Numerical analysis of laminar fluid flow and heat transfer in a parallel plate channel with normally in-line positioned plates
NUMERICAL ANALYSIS OF LAMINAR FLUID FLOW AND HEAT TRANSFER IN A PARALLEL PLATE CHANNEL WITH NORMALLY IN-LINE POSITIONED PLATES A Thesis by JOHN GRADY iVICMATH Submitted to the Office of Graduate Studies of Texas AkM University in partial... fulfillment of the requirements for the degree of MASTER OF SCIENCE December 1991 Major Subject: Mechanical Engineering NUMERICAL ANALYSIS OF LAMINAR FLUID FLOW AND HEAT TRANSFER IN A PARALLEL PLATE CHANNEI WITH NORMALLY IN-LINE POSITIONED PLATES A...
McMath, John Grady
Binary fish passage models for uniform and nonuniform flows
Binary fish passage models are considered by many fisheries managers to be the best 21 available practice for culvert inventory assessments and for fishway and barrier design. 22 Misunderstandings between different binary passage modeling approaches often arise, 23 however, due to differences in terminology, application and presentation. In this paper 24 one-dimensional binary fish passage models are reviewed and refined to clarify their 25 origins and applications. For uniform flow, a simple exhaustion-threshold (ET) model 26 equation is derived that predicts the flow speed threshold in a fishway or velocity barrier 27 that causes exhaustion at a given maximum distance of ascent. Flow speeds at or above 28 the threshold predict failure to pass (exclusion). Flow speeds below the threshold predict 29 passage. The binary ET model is therefore intuitive and easily applied to predict passage 30 or exclusion. It is also shown to be consistent with the distance-maximizing model. The 31 ET model s limitation to uniform flow is addressed by deriving a passage model that 32 accounts for nonuniform flow conditions more commonly found in the field, including 33 backwater profiles and drawdown curves. Comparison of these models with 34 experimental observations of volitional passage for Gambusia affinis in uniform and 35 nonuniform flows indicates reasonable prediction of binary outcomes (passage or 36 exclusion) if the flow speed is not near the threshold flow velocity. More research is 37 needed on fish behavior, passage strategies under nonuniform flow regimes and 38 stochastic methods that account for individual differences in swimming performance at or 39 near the threshold flow speed. Future experiments should track and measure ground 40 speeds of ascending fish to test nonuniform flow passage strategies and to improve model 41 predictions. Stochastic models, such as Monte-Carlo techniques, that account for 42 different passage performance among individuals and allow prediction of the percentage 43 of fish passing would be particularly useful near flow speed thresholds where binary 44 passage models are clearly limited.
Neary, Vincent S [ORNL
Diffusion driven object propulsion in density stratified fluids
An experimental study was conducted in order to verify the appropriateness of a two dimensional model of the flow creating diffusion driven object propulsion in density stratified fluids. Initial flow field experiments ...
Lenahan, Conor (Conor P.)
Inviscid Limits for a Stochastically Forced Shell Model of Turbulent Flow
We establish the anomalous mean dissipation rate of energy in the inviscid limit for a stochastic shell model of turbulent fluid flow. The proof relies on viscosity independent bounds for stationary solutions and on establishing ergodic and mixing properties for the viscous model. The shell model is subject to a degenerate stochastic forcing in the sense that noise acts directly only through one wavenumber. We show that it is hypo-elliptic (in the sense of Hormander) and use this property to prove a gradient bound on the Markov semigroup.
Susan Friedlander; Nathan Glatt-Holtz; Vlad Vicol
Modeling multiphase flow for high viscosity liquids: a study of vertical/inclined zero net liquid flow
This experimental study investigates the effects of inclination angle and fluid viscosity on zero net liquid flow (ZNLF). Predicting liquid holdup under ZNLF conditions is necessary in several types of petroleum industry operations. These include...
Rodriguez, Jose Ramon
VOLUME 81, NUMBER 24 P H Y S I C A L R E V I E W L E T T E R S 14 DECEMBER 1998 Camassa-Holm Equations as a Closure Model for Turbulent Channel and Pipe Flow
-Holm Equations as a Closure Model for Turbulent Channel and Pipe Flow Shiyi Chen,1 Ciprian Foias,1,2 Darryl D of the incompressible Navier-Stokes fluid. This approximation is tested on turbulent channel and pipe flows with steady Poiseuille flow occurs when a fluid in a straight channel, or pipe, is driven by a constant upstream pressure
Holm, Darryl D.
Modeling of fluids and waves with analytics and numerics
Capillary instability (Plateau-Rayleigh instability) has been playing an important role in experimental work such as multimaterial fiber drawing and multilayer particle fabrication. Motivated by complex multi-fluid geometries ...
Liang, Xiangdong, Ph. D. Massachusetts Institute of Technology
Water Modeling of Steel Flow, Air Entrainment and Filtration
Water Modeling of Steel Flow, Air Entrainment and Filtration Christoph Beckermann Associate Beckermann, C., "Water Modeling of Steel Flow, Air Entrainment and Filtration," in Proceedings of the 46th, 1992. #12;Abstract This paper presents an analysis of water modeling of steel pouring to study (1) air
Beckermann, Christoph
Criterion for purely elastic Taylor-Couette instability in the flows of shear-banding fluids
In the past twenty years, shear-banding flows have been probed by various techniques, such as rheometry, velocimetry and flow birefringence. In micellar solutions, many of the data collected exhibit unexplained spatio-temporal ...
Fardin, M. A.
Airfoil Shape Optimization for Transonic Flows of BetheZel'dovichThompson Fluids
of gasdynamics : 1 a @a @ s (1) where is the fluid density, a is the sound speed, and s is the entropy of thermodynamic conditions above the liquid/vapor coexistence curve, such that the fundamental derivative
Interfacial exchange relations for two-fluid vapor-liquid flow : a simplified regime map approach
A simplified approach is described for selection of the constitutive relations for the inter-phase exchange terms in the two-fluid code, THERMIT. The approach used distinguishes between pre-CHF and post-CHF conditions. ...
Kelly, J. E.
Flow through porous media : from mixing of fluids to triggering of earthquakes
Enhanced oil recovery by displacing oil with solvents such as carbon dioxide requires development of miscibility between the two fluids to maximize the displacement efficiency. Prevention of inadvertent triggering of ...
Jha, Birendra, Ph. D. Massachusetts Institute of Technology. Department of Civil and Environmental Engineering
A Semi-Lagrangian approach for dilute non-collisional fluid-particle flows
sprays [3, 4, 30, 52], environmental studies on pollutant transport [28, 54, 55, 58, 65], the formation viscosity of the fluid, and d the mass per unit volume of the droplets (see [19] and the references therein
Goudon, Thierry
A Parallel Implementation of the TOUGH2 Software Package for Large Scale Multiphase Fluid and Heat Flow Simulations
with ¢¡¤£¦¥§ ¨¡© blocks in a Yucca Mountain nuclear waste site study. Keywords. Ground water flow, grid partitioning management for the evaluation of the Yucca Mountain site as a repository for nuclear wastes. In this context of developing a 3D flow model of the Yucca Mountain site, involving computational grids of to blocks
Elmroth, Erik
6 blocks in a Yucca Mountain nuclear waste site study. Keywords. Ground water flow, grid of Energy's civilian nuclear waste management for the evaluation of the Yucca Mountain site as a repository is currently in charge of developing a 3D flow model of the Yucca Mountain site, involving computational grids
Flow in geothermal wells: Part III. Calculation model for self-flowing well
The theoretical model described predicts the temperature, pressure, dynamic dryness fraction, and void fraction along the vertical channel of two-phase flow. The existing data from operating wells indicate good agreement with the model. (MHR)
Bilicki, Z.; Kestin, J.; Michaelides, E.E.
Interacting cosmic fluids in power-law Friedmann-Robertson-Walker cosmological models
We provide a detailed description for power--law scaling Friedmann-Robertson-Walker cosmological scenarios dominated by two interacting perfect fluid components during the expansion. As a consequence of the mutual interaction between the two fluids, neither component is conserved separately and the energy densities are proportional to $1/t^{2}$. It is shown that in flat FRW cosmological models there can exist interacting superpositions of two perfect fluids (each of them having a positive energy density) which accelerate the expansion of the universe. In this family there also exist flat power law cosmological scenarios where one of the fluids may have a ``cosmological constant" or "vacuum energy" equation of state ($p =-\\rho$) interacting with the other component; this scenario exactly mimics the behavior of the standard flat Friedmann solution for a single fluid with a barotropic equation of state. These possibilities of combining interacting perfect fluids do not exist for the non-interacting mixtures of two perfect cosmic fluids, where the general solution for the scale factor is not described by power--law expressions and has a more complicated behavior. In this study is considered also the associated single fluid model interpretation for the interaction between two fluids.
Mauricio Cataldo; Patricio Mella; Paul Minning; Joel Saavedra
USER�S GUIDE of TOUGH2-EGS-MP: A Massively Parallel Simulator with Coupled Geomechanics for Fluid and Heat Flow in Enhanced Geothermal Systems VERSION 1.0
TOUGH2-EGS-MP is a parallel numerical simulation program coupling geomechanics with fluid and heat flow in fractured and porous media, and is applicable for simulation of enhanced geothermal systems (EGS). TOUGH2-EGS-MP is based on the TOUGH2-MP code, the massively parallel version of TOUGH2. In TOUGH2-EGS-MP, the fully-coupled flow-geomechanics model is developed from linear elastic theory for thermo-poro-elastic systems and is formulated in terms of mean normal stress as well as pore pressure and temperature. Reservoir rock properties such as porosity and permeability depend on rock deformation, and the relationships between these two, obtained from poro-elasticity theories and empirical correlations, are incorporated into the simulation. This report provides the user with detailed information on the TOUGH2-EGS-MP mathematical model and instructions for using it for Thermal-Hydrological-Mechanical (THM) simulations. The mathematical model includes the fluid and heat flow equations, geomechanical equation, and discretization of those equations. In addition, the parallel aspects of the code, such as domain partitioning and communication between processors, are also included. Although TOUGH2-EGS-MP has the capability for simulating fluid and heat flows coupled with geomechanical effects, it is up to the user to select the specific coupling process, such as THM or only TH, in a simulation. There are several example problems illustrating applications of this program. These example problems are described in detail and their input data are presented. Their results demonstrate that this program can be used for field-scale geothermal reservoir simulation in porous and fractured media with fluid and heat flow coupled with geomechanical effects.
Xiong, Yi [Colorado School of Mines; Fakcharoenphol, Perapon [Colorado School of Mines; Wang, Shihao [Colorado School of Mines; Winterfeld, Philip H. [Colorado School of Mines; Zhang, Keni [Lawrence Berkeley National Laboratory; Wu, Yu-Shu [Colorado School of Mines
User's manual for the Sandia Waste-Isolation Flow and Transport model (SWIFT).
This report describes a three-dimensional finite-difference model (SWIFT) which is used to simulate flow and transport processes in geologic media. The model was developed for use by the Nuclear Regulatory Commission in the analysis of deep geologic nuclear waste-disposal facilities. This document, as indicated by the title, is a user's manual and is intended to facilitate the use of the SWIFT simulator. Mathematical equations, submodels, application notes, and a description of the program itself are given herein. In addition, a complete input data guide is given along with several appendices which are helpful in setting up a data-input deck. Computer code SWIFT (Sandia Waste Isolation, Flow and Transport Model) is a fully transient, three-dimensional model which solves the coupled equations for transport in geologic media. The processes considered are: (1) fluid flow; (2) heat transport; (3) dominant-species miscible displacement; and (4) trace-species miscible displacement. The first three processes are coupled via fluid density and viscosity. Together they provide the velocity field on which the fourth process depends.
Reeves, Mark; Cranwell, Robert M.
Continuum-kinetic-microscopic model of lung clearance due to core-annular fluid entrainment
The human lung is protected against aspirated infectious and toxic agents by a thin liquid layer lining the interior of the airways. This airway surface liquid is a bilayer composed of a viscoelastic mucus layer supported by a fluid film known as the periciliary liquid. The viscoelastic behavior of the mucus layer is principally due to long-chain polymers known as mucins. The airway surface liquid is cleared from the lung by ciliary transport, surface tension gradients, and airflow shear forces. This work presents a multiscale model of the effect of airflow shear forces, as exerted by tidal breathing and cough, upon clearance. The composition of the mucus layer is complex and variable in time. To avoid the restrictions imposed by adopting a viscoelastic flow model of limited validity, a multiscale computational model is introduced in which the continuum-level properties of the airway surface liquid are determined by microscopic simulation of long-chain polymers. A bridge between microscopic and continuum levels is constructed through a kinetic-level probability density function describing polymer chain configurations. The overall multiscale framework is especially suited to biological problems due to the flexibility afforded in specifying microscopic constituents, and examining the effects of various constituents upon overall mucus transport at the continuum scale.
Mitran, Sorin, E-mail: firstname.lastname@example.com
Transient Heat and Material Flow Modeling of Friction Stir Processing of Magnesium Alloy using Threaded Tool
A three-dimensional transient computational fluid dynamics (CFD) model was developed to investigate the material flow and heat transfer during friction stir processing (FSP) in an AZ31B magnesium alloy. The material was assumed to be a non-Newtonian viscoplastic fluid, and the Zener-Hollomon parameter was used to describe the dependence of material viscosity on temperature and strain rate. The material constants used in the constitutive equation were determined experimentally from compression tests of the AZ31B Mg alloy under a wide range of strain rates and temperatures. A dynamic mesh method, combining both Lagrangian and Eulerian formulations, was used to capture the material flow induced by the movement of the threaded tool pin. Massless inert particles were embedded in the simulation domain to track the detailed history of material flow. The actual FSP was also carried out on a wrought Mg plate where temperature profiles were recorded by embedding thermocouples. The predicted transient temperature history was found to be consistent with that measured during FSP. Finally, the influence of the thread on the simulated results of thermal history and material flow was studied by comparing two models: one with threaded pin and the other with smooth pin surface.
Yu, Zhenzhen [ORNL; Zhang, Wei [ORNL; Choo, Hahn [ORNL; Feng, Zhili [ORNL
Fluid-rock interactions in the Rhine Graben: A thermodynamic model of the hydrothermal alteration observed in deep drilling
Deep drilling at Soultz-sous-Forets, France, on the western flanks of the Rhine Graben, has penetrated Hercynian granite underlying Mesozoic sediments. Veins are present throughout the drilled granite, and there are flows of warm water localized in fractures within the granite. Detailed mineralogical study of core material from the research drillhole EPSI has been carried out in order to assess the alteration history of the Soultz granite, part of the crystalline basement of the Rhine Graben. The results of the study have been used, in conjunction with analyses of present-day fluids from deep drilling in the Rhine Graben reported in the literature, to model thermodynamically the alteration process, and in particular to evaluate if it is likely to be continuing today. Reaction-path calculations show that if deep basinal brines, such as are known from sediments of the central Rhine Graben, react with Hercynian granite, they will form different alteration assemblages depending on both the path that the fluid follows (e.g., descending through sediments or through granite) and the extent of preexisting alteration of the granite. The calculations suggest that fluid now sampled from granite in EPS-1 achieved its peak temperature, c. 200{degrees}C while within Permo-Triassic sandstone. The modeling also indicates that present-day fluids from the Rhine Graben system are capable of producing the vein quartz and possibly also the baryte veins, seen in the EPSI core. Much of the alteration present in the granite in the vicinity of veins and fractures may have been produced by a flow regime similar to that prevailing today. 48 refs., 15 figs., 4 tabs.
Komninou, A.; Yardley, B.W.D. [Univ. of Leeds (United Kingdom)] [Univ. of Leeds (United Kingdom)
Model for the spatio-temporal intermittency of the energy dissipation in turbulent flows
Modeling the intermittent behavior of turbulent energy dissipation processes both in space and time is often a relevant problem when dealing with phenomena occurring in high Reynolds number flows, especially in astrophysical and space fluids. In this paper, a dynamical model is proposed to describe the spatio-temporal intermittency of energy dissipation rate in a turbulent system. This is done by using a shell model to simulate the turbulent cascade and introducing some heuristic rules, partly inspired by the well known $p$-model, to construct a spatial structure of the energy dissipation rate. In order to validate the model and to study its spatially intermittency properties, a series of numerical simulations have been performed. These show that the level of spatial intermittency of the system can be simply tuned by varying a single parameter of the model and that scaling laws in agreement with those obtained from experiments on fully turbulent hydrodynamic flows can be recovered. It is finally suggested that the model could represent a useful tool to simulate the spatio-temporal intermittency of turbulent energy dissipation in those high Reynolds number astrophysical fluids where impulsive energy release processes can be associated to the dynamics of the turbulent cascade.
Fabio Lepreti; Vincenzo Carbone; Pierluigi Veltri
The effect of various mixers on the viscosity and flow properties of an oil well drilling fluid
of Texas in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE January, 1957 MaJor SubJect. Petroleum Englneerlng THE EFFECT OF VARIOUS MIXERS ON THE VISCOSITY AND FLOW PROPERTIES QF AN OIL WELL DRILLING FLUID A Thesis... on the 300 rpm Farm V-G Meter Reading 15 The Effect of Various Mixers on the 600 rpm Farm V-G Meter Reading 15 The Effect of Various Mixers on the Plastic Viscosity of a Bentonite Mud 16 Temperature Variation of the Drilling Mud Mixed in Variou...
Spannagel, Johnny Allen
ShowFlow: A practical interface for groundwater modeling
ShowFlow was created to provide a user-friendly, intuitive environment for researchers and students who use computer modeling software. What traditionally has been a workplace available only to those familiar with command-line based computer systems is now within reach of almost anyone interested in the subject of modeling. In the case of this edition of ShowFlow, the user can easily experiment with simulations using the steady state gaussian plume groundwater pollutant transport model SSGPLUME, though ShowFlow can be rewritten to provide a similar interface for any computer model. Included in this thesis is all the source code for both the ShowFlow application for Microsoft{reg sign} Windows{trademark} and the SSGPLUME model, a User's Guide, and a Developer's Guide for converting ShowFlow to run other model programs. 18 refs., 13 figs.
Tauxe, J.D.
Nonlinear elasto-plastic model for dense granular flow
This work proposes a model for granular deformation that predicts the stress and velocity profiles in well-developed dense granular flows. Recent models for granular elasticity (Jiang and Liu 2003) and rate-sensitive plastic flow (Jop et al. 2006) are reformulated and combined into one universal granular continuum law, capable of predicting flowing regions and stagnant zones simultaneously in any arbitrary 3D flow geometry. The unification is performed by justifying and implementing a Kroner-Lee elasto-plastic decomposition, with care taken to ensure certain continuum physical principles are necessarily upheld. The model is then numerically implemented in multiple geometries and results are compared to experiments and discrete simulations.
Ken Kamrin
Technologies Program Office Program Manager: Mr. Gurpreet Singh Petrodiesel vs. Biodiesel 2 Primary Breakup Inner Nozzle Flow Influence of Physical and Chemical properties of...
Use of Geophysical Techniques to Characterize Fluid Flow in a Geothermal Reservoir
Project objectives: Joint inversion of geophysical data for ground water flow imaging; Reduced the cost in geothermal exploration and monitoring; & Combined passive and active geophysical methods.
A correction function method to solve incompressible fluid flows to high accuracy with immersed geometries
Numerical simulations of incompressible viscous flows in realistic configurations are increasingly important in many scientific and engineering fields. In Aeronautics, for instance, relatively cheap numerical computations ...
Marques, Alexandre Noll
REYNOLDS STRESS MODEL IMPLEMENTATION FOR HYPERSONIC FLOW SIMULATIONS Arianna Bosco, PhD student, 52056 Aachen, Germany Abstract The simulation of hypersonic flows presents some difficulties due of the model is analyzed. 1 Introduction The aerodynamic design of hypersonic inlets is a criti- cal issue
A phenomenological model for the flow resistance over submerged vegetation
A phenomenological model for the flow resistance over submerged vegetation Alexandra G. Konings,1: Konings, A. G., G. G. Katul, and S. E. Thompson (2012), A phenomenological model for the flow resistance [2002]. In this paper, a phenomenological approach is used to describe the momentum transfer
Katul, Gabriel
NMR imaging techniques and applications in the flow behavior of fluids in porous media
proton magnetic resonance technique can be used to determine the oil saturation in the pores of a rock. The NMR system can produce images of the molecules under investigation because the signals recorded are obtained directly from fluids contained... in liquids as well. This should enable us to obtain additional information about the fluids in the rock '4. Spin-spin relaxation has a characteristic time T~. T~ is the time constant for the decay of the precessing R-Zo component of the magnetization...
Halimi, Hassan I
A Mechanical Fluid-Dynamical Model For Ground Movements At Campi...
Mechanical Fluid-Dynamical Model For Ground Movements At Campi Flegrei Caldera Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: A Mechanical...
Lattice discretization effects on the critical parameters of model nonpolar and polar fluids
Lattice discretization effects on the critical parameters of model nonpolar and polar fluids Sarvin Moghaddam Department of Chemical Engineering, University of Maryland, College Park, Maryland 20742 Athanassios Z. Panagiotopoulosa) Department of Chemical Engineering, Princeton University, Princeton, New
Numerical and analytical modeling of heat transfer between fluid and fractured rocks
Modeling of heat transfer between fluid and fractured rocks is of particular importance for energy extraction analysis in EGS, and therefore represents a critical component of EGS design and performance evaluation. In ...
Li, Wei, S.M. Massachusetts Institute of Technology
A next-generation modeling capability assesses wind turbine array fluid dynamics and aeroelastic simulations
A next-generation modeling capability assesses wind turbine array fluid dynamics and aeroelastic of multi-megawatt turbines requires a new generation of modeling capability to assess individual turbine. Key Result The work is generating several models, including actuator line models of several wind
Solyndra Facts vs. Fiction: Cash Flow Modeling
Questions have been raised about a quote selectively pulled from an Aug. 20, 2009 email to make it look like Solyndra would run out of cash by Sept. 2011. To be clear, the analysis addressed in that email did not refer to Solyndra�s corporate cash flow, but rather the cash flow for a subsidiary of Solyndra � the �Fab 2 Project Company.
A two-fluid model for relativistic heat conduction
Three years ago it was presented in these proceedings the relativistic dynamics of a multi-fluid system together with various applications to a set of topical problems [1]. In this talk, I will start from such dynamics and present a covariant formulation of relativistic thermodynamics which provides us with a causal constitutive equation for the propagation of heat in a relativistic setting.
L�pez-Monsalvo, C�sar S. [Instituto de Ciencias Nucleares, Universidad Nacional Aut�noma de M�xico (Mexico)
Vortical Inviscid Flows with Two-Way Solid-Fluid Coupling
, the net force acting on a solid immersed in an irrotational and inviscid flow is zero. For instance methods are used to accurately calculate forces in mechanical engineering applications such as airfoils [6, a sphere in an inviscid constant uniform flow would experience zero drag which is clearly incorrect. Our
Lee, WonSook
A Well-Balanced Scheme For Two-Fluid Flows In Variable Cross-Section ducts
, ) p = p(, s, ), h = h(, s, ). (21) Then in these variables the sound speed c satisfies c2 = p = h. (22 of a mixture of two compressible fluids (a gas (1) and a liquid (2), for instance) in a cross-section duct
Study of Laminar Flow Forced Convection Heat Transfer Behavior of a Phase Change Material Fluid
at the entrance of the tube. Results were also obtained for the phase change process under hydro dynamically and thermally fully developed conditions. In case of a smooth circular tube with phase change material (PCM) fluid, results of Nusselt number were obtained...
Ravi, Gurunarayana
Fusion Engineering and Design 82 (2007) 22172225 Integrated thermo-fluid analysis towards helium flow
Fusion Engineering and Design 82 (2007) 22172225 Integrated thermo-fluid analysis towards helium. Andob, I. Komadab a Fusion Engineering Sciences, Mechanical and Aerospace Eng. Department, University the ITER test blanket module (TBM) warrants the need of extensive computer aided engineering (CAE
LETTER TO THE EDITOR AC Electric-Field-Induced Fluid Flow in Microelectrodes
glass substrates. The electrodes were made from a series of metal layers: 10 nm Ti, 10 nm Pd, 100 nm Au relaxation time, with a reproducible pattern occurring close to and across the electrode surface. This paper reports measurements of the fluid velocity as a function of frequency and position across the electrode
Using a multiphase flow code to model the coupled effects of repository consolidation and multiphase brine and gas flow at the Waste Isolation Pilot Plant
Long-term repository assessment must consider the processes of (1) gas generation, (2) room closure and expansions due to salt creep, and (3) multiphase (brine and gas) fluid flow, as well as the complex coupling between these three processes. The mechanical creep closure code SANCHO was used to simulate the closure of a single, perfectly sealed disposal room filled with water and backfill. SANCHO uses constitutive models to describe salt creep, waste consolidation, and backfill consolidation, Five different gas-generation rate histories were simulated, differentiated by a rate multiplier, f, which ranged from 0.0 (no gas generation) to 1.0 (expected gas generation under brine-dominated conditions). The results of the SANCHO f-series simulations provide a relationship between gas generation, room closure, and room pressure for a perfectly sealed room. Several methods for coupling this relationship with multiphase fluid flow into and out of a room were examined. Two of the methods are described.
Freeze, G.A. [INTERA Inc., Albuquerque, NM (United States); Larson, K.W.; Davies, P.B.; Webb, S.W. [Sandia National Labs., Albuquerque, NM (United States)
Modeling Granular Materials as Compressible Non-Linear Fluids: Heat Transfer Boundary Value Problems
We discuss three boundary value problems in the flow and heat transfer analysis in flowing granular materials: (i) the flow down an inclined plane with radiation effects at the free surface; (ii) the natural convection flow between two heated vertical walls; (iii) the shearing motion between two horizontal flat plates with heat conduction. It is assumed that the material behaves like a continuum, similar to a compressible nonlinear fluid where the effects of density gradients are incorporated in the stress tensor. For a fully developed flow the equations are simplified to a system of three nonlinear ordinary differential equations. The equations are made dimensionless and a parametric study is performed where the effects of various dimensionless numbers representing the effects of heat conduction, viscous dissipation, radiation, and so forth are presented.
Massoudi, M.C.; Tran, P.X.
Properties of CO2-Rich Pore Fluids and Their Effect on Porosity...
More Documents & Publications Imaging, Characterizing, and Modeling of Fracture Networks and Fluid Flow in EGS Reservoirs An integrated experimental and numerical...
The overall objective of the project was to verify the applicability of the FCMOM approach to the kinetic equations describing the particle flow dynamics. For monodispersed systems the fundamental equation governing the particle flow dynamics is the Boltzmann equation. During the project, the FCMOM was successfully applied to several homogeneous and in-homogeneous problems in different flow regimes, demonstrating that the FCMOM has the potential to be used to solve efficiently the Boltzmann equation. However, some relevant issues still need to be resolved, i.e. the homogeneous cooling problem (inelastic particles cases) and the transition between different regimes. In this report, the results obtained in homogeneous conditions are discussed first. Then a discussion of the validation results for in-homogeneous conditions is provided. And finally, a discussion will be provided about the transition between different regimes. Alongside the work on development of FCMOM approach studies were undertaken in order to provide insights into anisotropy or particles kinetics in riser hydrodynamics. This report includes results of studies of multiphase flow with unequal granular temperatures and analysis of momentum re-distribution in risers due to particle-particle and fluid-particle interactions. The study of multiphase flow with unequal granular temperatures entailed both simulation and experimental studies of two particles sizes in a riser and, a brief discussion of what was accomplished will be provided. And finally, a discussion of the analysis done on momentum re-distribution of gas-particles flow in risers will be provided. In particular a discussion of the remaining work needed in order to improve accuracy and predictability of riser hydrodynamics based on two-fluid models and how they can be used to model segregation in risers.
Moses Bogere
Two fluid anisotropic dark energy models in a scale invariant theory
We have investigated some anisotropic dark energy models in a simple scale invariant theory of gravity. The anisotropic nature of the universe is considered through a spatially homogeneous and anisotropic Bianchi type $V$ space-time. The matter field is considered to be composed of two non interacting fluids namely the usual bulk viscous fluid and that of the dark energy fluid. Pressure anisotropy is considered along different spatial directions. From the constructed cosmological models, we found a dynamic pressure anisotropy which continues along with the cosmic expansion. The models are found to be mostly dominated by phantom behaviour. The presence of bulk viscous fluid does not affect substantially the general nature of the cosmic dynamics. The scale invariant theory of gravity is found to have a dominant role in the cosmic dynamics and help the de Sitter universe to exit from a catastrophic situation.
Tripathy, S K; Sahoo, P K
Data-flow graphs as a model of parallel complexity
A new model of parallel computation based on data-flow graphs is introduced, which is specifically oriented towards complexity theory. Data-flow graphs are capable of illustrating properties of synchronous, asynchronous, and nondeterministic computations. Sufficient conditions are derived for asynchronous data-flow graphs to be determinate, i.e., all possible computations are finite and yield the same result. For determinate graphs, it is shown that the synchronous computation is as fast as any asynchronous computation. An algorithm is presented that transforms a nondeterminate data-flow graphs into a synchronous determinate one. The basic data-flow graph idea is extended into a model with greater potential parallelism, called the Uniform Data Flow Graph Family (UDFGF) Model. It is proved that time and space for the UDFGF model are polynomially related to reversal and space for the Turing Machine model, in both the deterministic and nondeterministic cases. In addition to forming an abstract computational model, data-flow graphs are parallel programs for real multiprocessors. Given a data flow graph program and a multiprocessor, each node of the graph must be assigned to one of the processors. It is proved that this problem is intractable, and a practical algorithm to find approximate solutions for it is presented.
Campbell, M.L.
Thesis: Transient Modeling and Construc3on of a Fluid Based Electrocaloric Effect (ECE) Refrigera3on Cycle
Thesis: Transient Modeling and Construc3on of a Fluid Based Electrocaloric Effect (ECE) Refrigera3on Cycle Nathan Haggerty M.S. Student Mechanical · Demonstrate the feasibility of a fluid based electrocaloric refrigera3on cycle · ECE
A new analytic-adaptive model for EGS assessment, development...
Categorical Exclusion Determination Imaging, Characterizing, and Modeling of Fracture Networks and Fluid Flow in EGS Reservoirs Predicting Stimulation Response...
Shearing Flows in Liquid Crystal Models
The liquid crystal phase is a phase of matter between the solid and liquid phase whose flow is characterized by a velocity field and a director field which describes locally the orientation of the liquid crystal. In this ...
Dorn, Timothy
Formulation, Implementation and Validation of a Two-Fluid model in a Fuel Cell CFD Code
Water management is one of the main challenges in PEM Fuel Cells. While water is essential for membrane electrical conductivity, excess liquid water leads to ooding of catalyst layers. Despite the fact that accurate prediction of two-phase transport is key for optimal water management, understanding of the two-phase transport in fuel cells is relatively poor. Wang et. al. [1], [2] have studied the two-phase transport in the channel and diffusion layer separately using a multiphase mixture model. The model fails to accurately predict saturation values for high humidity inlet streams. Nguyen et. al. [3] developed a two-dimensional, two-phase, isothermal, isobaric, steady state model of the catalyst and gas diffusion layers. The model neglects any liquid in the channel. Djilali et. al. [4] developed a three-dimensional two-phase multicomponent model. The model is an improvement over previous models, but neglects drag between the liquid and the gas phases in the channel. In this work, we present a comprehensive two- fluid model relevant to fuel cells. Models for two-phase transport through Channel, Gas Diffusion Layer (GDL) and Channel-GDL interface, are discussed. In the channel, the gas and liquid pressures are assumed to be same. The surface tension effects in the channel are incorporated using the continuum surface force (CSF) model. The force at the surface is expressed as a volumetric body force and added as a source to the momentum equation. In the GDL, the gas and liquid are assumed to be at different pressures. The difference in the pressures (capillary pressure) is calculated using an empirical correlations. At the Channel-GDL interface, the wall adhesion affects need to be taken into account. SIMPLE-type methods recast the continuity equation into a pressure-correction equation, the solution of which then provides corrections for velocities and pressures. However, in the two-fluid model, the presence of two phasic continuity equations gives more freedom and more complications. A general approach would be to form a mixture continuity equation by linearly combining the phasic continuity equations using appropriate weighting factors. Analogous to mixture equation for pressure correction, a difference equation is used for the volume/phase fraction by taking the difference between the phasic continuity equations. The relative advantages of the above mentioned algorithmic variants for computing pressure correction and volume fractions are discussed and quantitatively assessed. Preliminary model validation is done for each component of the fuel cell. The two-phase transport in the channel is validated using empirical correlations. Transport in the GDL is validated against results obtained from LBM and VOF simulation techniques. The Channel-GDL interface transport will be validated against experiment and empirical correlation of droplet detachment at the interface. References [1] Y. Wang S. Basu and C.Y. Wang. Modeling two-phase flow in pem fuel cell channels. J. Power Sources, 179:603{617, 2008. [2] P. K. Sinha and C. Y. Wang. Liquid water transport in a mixed-wet gas diffusion layer of a polymer electrolyte fuel cell. Chem. Eng. Sci., 63:1081-1091, 2008. [3] Guangyu Lin and Trung Van Nguyen. A two-dimensional two-phase model of a pem fuel cell. J. Electrochem. Soc., 153(2):A372{A382, 2006. [4] T. Berning and N. Djilali. A 3d, multiphase, multicomponent model of the cathode and anode of a pem fuel cell. J. Electrochem. Soc., 150(12):A1589{A1598, 2003.
Kunal Jain, Vernon Cole, Sanjiv Kumar and N. Vaidya
Bypass Flow Study
The purpose of the fluid dynamics experiments in the MIR (Matched Index of-Refraction) flow system at Idaho National Laboratory (INL) is to develop benchmark databases for the assessment of Computational Fluid Dynamics (CFD) solutions of the momentum equations, scalar mixing, and turbulence models for the flow ratios between coolant channels and bypass gaps in the interstitial regions of typical prismatic standard fuel element (SFE) or upper reflector block geometries of typical Modular High-temperature Gas-cooled Reactors (MHTGR) in the limiting case of negligible buoyancy and constant fluid properties. The experiments use Particle Image Velocimetry (PIV) to measure the velocity fields that will populate the bypass flow study database.
Richard Schultz
Mathematical Model Analysis for Hg Flow
Properties (25 C ) Density 13.546 kg/L Sound Speed 1451 m/s Viscosity 1.526E-3 kg/sm Dynamic Viscosity 1Mechanism of Jet Breakup & Atomization R.D. Reitz and F.V. Bracco, Mechanism of atomization of a liquid jet,Phys. Fluids, Vol.25, No.10,Oct.1982 Environment Liquid Properties Viscosity Density Jet Breakup & Atomization
McDonald, Kirk
Scalar field inflation and Shan-Chen fluid models
A scalar field equivalent to a non-ideal "dark energy fluid" obeying a Shan-Chen-like equation of state is used as the background source of a flat Friedmann-Robertson-Walker cosmological spacetime to describe the inflationary epoch of our universe. Within the slow-roll approximation, a number of interesting features are presented, including the possibility to fulfill current observational constraints as well as a graceful exit mechanism from the inflationary epoch.
Donato Bini; Andrea Geralico; Daniele Gregoris; Sauro Succi
Molecular modelling and simulation of the surface tension of real quadrupolar fluids
Molecular modelling and simulation of the surface tension of fluids with force fields is discussed. 29 real fluids are studied, including nitrogen, oxygen, carbon dioxide, carbon monoxide, fluorine, chlorine, bromine, iodine, ethane, ethylene, acetylene, propyne, propylene, propadiene, carbon disulfide, sulfur hexafluoride, and many refrigerants. The fluids are represented by two-centre Lennard-Jones plus point quadrupole models from the literature. These models were adjusted only to experimental data of the vapour pressure and saturated liquid density so that the results for the surface tension are predictions. The deviations between the predictions and experimental data for the surface tension are of the order of 20 percent. The surface tension is usually overestimated by the models. For further improvements, data on the surface tension can be included in the model development. A suitable strategy for this is multi-criteria optimization based on Pareto sets. This is demonstrated using the model for carbon dioxide as an example.
Stephan Werth; Katrin St�bener; Peter Klein; Karl-Heinz K�fer; Martin Horsch; Hans Hasse
Molecular modelling and simulation of the surface tension of fluids with force fields is discussed. 29 real fluids are studied, including nitrogen, oxygen, carbon dioxide, carbon monoxide, fluorine, chlorine, bromine, iodine, ethane, ethylene, acetylene, propyne, propylene, propadiene, carbon disulfide, sulfur hexafluoride, and many refrigerants. The fluids are represented by two-centre Lennard-Jones plus point quadrupole models from the literature. These models were adjusted only to experimental data of the vapour pressure and saturated liquid density so that the results for the surface tension are predictions. The deviations between the predictions and experimental data for the surface tension are of the order of 20 percent. The surface tension is usually overestimated by the models. For further improvements, data on the surface tension can be included in the model development. A suitable strategy for this is multi-criteria optimization based on Pareto sets. This is demonstrated using the model for carbon d...
Werth, Stephan; Klein, Peter; K�fer, Karl-Heinz; Horsch, Martin; Hasse, Hans
On the Fundamental Unsteady Fluid Dynamics of Shock-Induced Flows through Ducts
Unsteady shock wave propagation through ducts has many applications, ranging from blast wave shelter design to advanced high-speed propulsion systems. The research objective of this study was improved fundamental understanding of the transient flow...
Mendoza, Nicole Renee
Review of fluid flow and convective heat transfer within rotating disk cavities
-00975626,version1-8Apr2014 Author manuscript, published in "International Journal of Thermal Sciences 67 based on and r. Rej Jet Reynolds number based on W and D. ReU Cross-flow Reynolds number Ro Rossby
Fluid Flow In The Resurgent Dome Of Long Valley Caldera- Implications...
caldera was cooled to normal thermal conditions by vigorous hydrothermal activity in the past, and that a present-day hot water flow system is responsible for local hot anomalies,...
Multiphase flow and Encapsulation simulations using the moment of fluid method 1
, spray cooling, icing, combustion and agricultural irrigation. The instability of the interface, mass exist for the accurate and effi- cient computation of multiphase flows. First, the density and viscosity
Sussman, Mark
Under consideration for publication in J. Fluid Mech. 1 Nonlinear free surface flows past a semi-
- infinite flat plate in water of finite depth M. M A L E E W O N G 1 AND R. H. J. G R I M S H A W2 1 ??) We consider the steady free surface two-dimensional flow past a semi-infinite flat plate in water (draft) of the depressed plate. For small d and subcritical flows, we may use the linearized problem
The role of homology in fluid vortices I: non-relativistic flow
The methods of singular and de Rham homology and cohomology are reviewed to the extent that they are applicable to the structure and motion of vortices. In particular, they are first applied to the concept of integral invariants. After a brief review of the elements of fluid mechanics, when expressed in the language of exterior differential forms and homology theory, the basic laws of vortex theory are shown to be statements that are rooted in the homology theory of integral invariants.
D. H. Delphenich
Elevated thermal maturation in Pennsylvanian rocks, Cherokee basin, southeastern Kansas: Importance of regional fluid flow
Thermal history of sedimentary basins is commonly assumed to be dominated by burial heating. Marked contrast between reconstructed burial temperatures and other temperature determinations would suggest alternative processes. In the Cherokee basin of southeastern Kansas, reconstruction of burial and thermal history indicates that basal Pennsylvanian strata were not buried more than 1.8 km, and should have reached only about 90C. However, the study of Pennsylvanian rocks of the Cherokee basin indicates that higher temperatures were reached and that the pattern of thermal maturation is inconsistent with simple burial heating. Regional pattern of vitrinite reflectance reveals several warm spots' where thermal maturation is elevated above the regional background. Primary fluid inclusions in late Ca-Mg-Fe carbonate cements yield homogenization-temperature modes or petrographically consistent populations ranging from 100 to 150C. These data suggest that the samples experienced at least those temperatures, hence fluid inclusions closely agree with vitrinite and Rock-Eval. Elevated temperatures, warm spots, confined thermal spikes, a low R{sub m} gradient argue against simple burial heating. These observations are consistent with regional invasion of warm fluids, probably from the Ouachita-Arkoma system, and their subsequent upward migration into Pennsylvanian strata through faults and fractures. Petroleum exploration should consider the possibility of regionally elevated thermal maturation levels with even more elevated local maxima. Consequences may include local generation of hydrocarbons or local changes in diagenetic patterns.
Wojcik, K.M.; Goldstein, R.H.; Walton, A.W. (Univ. of Kansas, Lawrence (United States)); Barker, C.E. (Geological Survey, Denver, CO (United States))
The primary purpose of the tank mixing and sampling demonstration program is to mitigate the technical risks associated with the ability of the Hanford tank farm delivery and celtification systems to measure and deliver a uniformly mixed high-level waste (HLW) feed to the Waste Treatment and Immobilization Plant (WTP) Uniform feed to the WTP is a requirement of 24590-WTP-ICD-MG-01-019, ICD-19 - Interface Control Document for Waste Feed, although the exact definition of uniform is evolving in this context. Computational Fluid Dynamics (CFD) modeling has been used to assist in evaluating scaleup issues, study operational parameters, and predict mixing performance at full-scale.
Multiparticle imaging technique for two-phase fluid flows using pulsed laser speckle velocimetry. Final report, September 1988--November 1992
A Novel Hyperbolization Procedure for The Two-Phase Six-Equation Flow Model
We introduce a novel approach for the hyperbolization of the well-known two-phase six equation flow model. The six-equation model has been frequently used in many two-phase flow applications such as bubbly fluid flows in nuclear reactors. One major drawback of this model is that it can be arbitrarily non-hyperbolic resulting in difficulties such as numerical instability issues. Non-hyperbolic behavior can be associated with complex eigenvalues that correspond to characteristic matrix of the system. Complex eigenvalues are often due to certain flow parameter choices such as the definition of inter-facial pressure terms. In our method, we prevent the characteristic matrix receiving complex eigenvalues by fine tuning the inter-facial pressure terms with an iterative procedure. In this way, the characteristic matrix possesses all real eigenvalues meaning that the characteristic wave speeds are all real therefore the overall two-phase flowmodel becomes hyperbolic. The main advantage of this is that one can apply less diffusive highly accurate high resolution numerical schemes that often rely on explicit calculations of real eigenvalues. We note that existing non-hyperbolic models are discretized mainly based on low order highly dissipative numerical techniques in order to avoid stability issues.
Samet Y. Kadioglu; Robert Nourgaliev; Nam Dinh
Macroscopic limit of a one-dimensional model for aging fluids
We study a one-dimensional equation arising in the multiscale modeling of some non-Newtonian fluids. At a given shear rate, the equation provides the instantaneous mesoscopic response of the fluid, allowing to compute the corresponding stress. In a simple setting, we study the well-posedness of the equation and next the long-time behavior of its solution. In the limit of a response of the fluid much faster than the time variations of the ambient shear rate, we derive some equivalent macroscopic differential equations that relate the shear rate and the stress. Our analytical conclusions are confronted to some numerical experiments. The latter quantitatively confirm our derivations.
David Benoit; Claude Le Bris; Tony Leli�vre
Generating expansion model incorporating compact DC power flow equations
This paper presents a compact method of incorporating the spatial dimension into the generation expansion problem. Compact DC power flow equations are used to provide real-power flow coordination equations. Using these equations the marginal contribution of a generator to th total system loss is formulated as a function of that generator`s output. Incorporating these flow equations directly into the MIP formulation of the generator expansion problem results in a model that captures a generator`s true net marginal cost, one that includes both the cost of generation and the cost of transport. This method contrasts with other methods that iterate between a generator expansion model and an optimal power flow model. The proposed model is very compact and has very good convergence performance. A case study with data from Kenya is used to provide a practical application to the model.
Nderitu, D.G.; Sparrow, F.T.; Yu, Z. [Purdue Inst. for Interdisciplinary Engineering Studies, West Lafayette, IN (United States)
Periodic Exponential Shear of Complex Fluids
We define a class of flows with exponential kinematics termed Periodic Exponential Shear (PES) flow which involve periodic exponential stretching of fluid elements along with their rotation. We exhibit analytical and numerical results for PES flow by using the Oldroyd-B model for viscoelastic fluids. We calculate the growth in the shear and the normal stresses analytically as well as demonstrate that repeated application of the flow leads to stable oscillatory shear and normal stresses. We define a material function applicable to a periodic, unsteady shear flow and show numerically that this material function exhibits deformation-rate thickening behavior for viscoelastic fluids subject to PES flow. We demonstrate the feasibility of PES flow by presenting preliminary experimental results from a controlled-strain rate rheometer, using a Newtonian mineral oil.
Chirag Kalelkar; Gareth McKinley
Three-dimensional computer modeling of particulate flow around dust monitors
SOLA-DM is a three-dimensional finite-difference computer code designed to model the dynamics of an incompressible fluid and the transport of discrete particulate material around obstacles impervious to flow. The numerical methods used in this code are described. SOLA-DM was used to predict the particle flux sampled by the 10-mm Dorr-Oliver Cyclone and MINIRAM dust monitors. Various geometric and dynamic variations of monitor and airflow combinations were tested. The code predictions are shown in computer-generated graphic plots.
Nichols, B.D.; Gregory, W.S.
Modeling of material and energy flow in an EBCHR casting system
A numerical and experimental analysis is made of fluid flow and heat transfer in a continuous casting system with an electron-beam energy source. For a cylindrical ingot confined in a water-cooled crucible, a two-dimensional, steady-state model is developed which includes the effects of free convection in the pool and conduction in the two-phase and solid regions. A modified Galerkin finite element method is used to solve for the flow and temperature fields simultaneously with the upper and lower boundaries of the pool. The calculation grid deforms along vertical spines as these phase boundaries move. Heat flows are measured in a steady-state experiment involving a short ingot and no pouring. Heat transfer coefficients representing contact resistance are determined, and measured heat flows are compared with model values. Flow and temperature fields along with solidification-zone boundaries are calculated for the experimental case and a case in which the ingot cooling is improved.
Westerberg, K.W. [Aspen Technology, Inc., Cambridge, MA (United States); McClelland, M.A. [Lawrence Livermore National Lab., CA (United States)
Modeling and Algorithmic Approaches to Constitutively-Complex, Micro-structured Fluids
The team for this Project made significant progress on modeling and algorithmic approaches to hydrodynamics of fluids with complex microstructure. Our advances are broken down into modeling and algorithmic approaches. In experiments a driven magnetic bead in a complex fluid accelerates out of the Stokes regime and settles into another apparent linear response regime. The modeling explains the take-off as a deformation of entanglements, and the longtime behavior is a nonlinear, far-from-equilibrium property. Furthermore, the model has predictive value, as we can tune microstructural properties relative to the magnetic force applied to the bead to exhibit all possible behaviors. Wave-theoretic probes of complex fluids have been extended in two significant directions, to small volumes and the nonlinear regime. Heterogeneous stress and strain features that lie beyond experimental capability were studied. It was shown that nonlinear penetration of boundary stress in confined viscoelastic fluids is not monotone, indicating the possibility of interlacing layers of linear and nonlinear behavior, and thus layers of variable viscosity. Models, algorithms, and codes were developed and simulations performed leading to phase diagrams of nanorod dispersion hydrodynamics in parallel shear cells and confined cavities representative of film and membrane processing conditions. Hydrodynamic codes for polymeric fluids are extended to include coupling between microscopic and macroscopic models, and to the strongly nonlinear regime.
Forest, Mark Gregory [University of North Carolina at Chapel Hill] [University of North Carolina at Chapel Hill
Perturbative analysis of sheared flow Kelvin-Helmholtz instability in a weakly relativistic magnetized electron fluid
In the interaction of intense lasers with matter/plasma, energetic electrons having relativistic energies get created. These energetic electrons can often have sheared flow profiles as they propagate through the plasma medium. In an earlier study [Phys. Plasmas 17, 022101 (2010)], it was shown that a relativistic sheared electron flow modifies the growth rate and threshold condition of the conventional Kelvin-Helmholtz instability. A perturbative analytic treatment for the case of weakly relativistic regime has been provided here. It provides good agreement with the numerical results obtained earlier.
Sundar, Sita; Das, Amita; Kaw, Predhiman [Institute for Plasma Research, Bhat, Gandhinagar-382428 (India)
Submarine landslide flows simulation through centrifuge modelling
) ........ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Figure 2.7: Failure at Helsinki Harbour , Finland in 1936 (after Andresen and Bjerrum, 1967... ) ......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 Figure 2.18: Energy conversion for debris flows (modified after Iverson, 1997) .......................................................................................... 50 Figure 2.19: Schematic cross-section defini ng H...
Gue, Chang Shin
Modelling macroeconomic flows related to large ensembles
, including, say, oil prices, interest rates, etc; dynamics of shares markets are governed by information are illustrated by flows of a liquid between interconnected reservoirs, where the heights of different reservoirs is changing with time, and movement of the liquid between the reservoirs is governed by gravity, see Figure 1
Schellekens, Michel P.
A Two Pressure Numerical Model of Two Fluid Mixing \\Lambda
by comparison to the incompressible limit. For the purpose of this comparison, we present a newly obtained ana, for example in pipeline flow and the performance of inertial confinement fusion reactors; it is important behav ior of a multifluid mixture without direct simulation of all its microscopic details. From
New York at Stoney Brook, State University of
A turbulence model for buoyant flows based on vorticity generation.
A turbulence model for buoyant flows has been developed in the context of a k-{var_epsilon} turbulence modeling approach. A production term is added to the turbulent kinetic energy equation based on dimensional reasoning using an appropriate time scale for buoyancy-induced turbulence taken from the vorticity conservation equation. The resulting turbulence model is calibrated against far field helium-air spread rate data, and validated with near source, strongly buoyant helium plume data sets. This model is more numerically stable and gives better predictions over a much broader range of mesh densities than the standard k-{var_epsilon} model for these strongly buoyant flows.
Domino, Stefan Paul; Nicolette, Vernon F.; O'Hern, Timothy John; Tieszen, Sheldon R.; Black, Amalia Rebecca
A Novel Approach For the Simulation of Multiple Flow Mechanisms and Porosities in Shale Gas Reservoirs
The state of the art of modeling fluid flow in shale gas reservoirs is dominated by dual porosity models that divide the reservoirs into matrix blocks that significantly contribute to fluid storage and fracture networks which principally control...
Yan, Bicheng
Modeling and design of semi-solid flow batteries
A three-dimensional dynamic model of the recently introduced semi-solid flow battery system is developed and applied to address issues with important design and operation implications. Because of the high viscosity of ...
Brunini, Victor Eric
Two-fluid flowing equilibria of compact plasmas Loren C. Steinhauer
or presence of a j�?B force. The force-free class may have significant flows. Spheromaks are in this class-force-free class is energetically favorable. This sheds light on the FRC-spheromak bifurcation observed- perimentally only in certain arrangements reversed-field pinch, spheromak and then only in the central ``core
Washington at Seattle, University of
Slip Flow Fluid-Structure-Interaction J. van Rij, T. Harman, T. Ameel*
per unit mass E Young's modulus of elasticity, ( )KGGK 39 + f force per unit volume FD drag force Fo Fourier number, 2 Dt G shear modulus of elasticity * Corresponding author. Tel.: +1-801-585-9730; fax: +1 moment of inertia K bulk modulus of elasticity rsK momentum exchange coefficient slip rsK slip flow
Utah, University of
Project objective: A New Geothermal Well Imaging Tool. 1.To develop a robust and easily deployable DTPS for monitoring in geothermal wells; and 2. Develop the associated analysis methodology for flow imaging; and?when possible by wellbore conditions?to determine in situthermal conductivity and basal heat flux.
Numerical simulation of flow of shear-thinning fluids in corrugated channels
is subjected to a periodic increase and decrease in cross-section area. Such conditions are frequently observed in the flow of blood through blood vessels, movement of lubricating oils through the ground during the oil extraction process, in the process...
Aiyalur Shankaran, Rohit
Different approximations of shallow fluid flow over an obstacle B. T. Nadiga and L. G. Margolin
sets of shallow water equations, representing different levels of approximation are considered the dispersive shallow water DSW solutions and those of the highly simplified, hyperbolic shallow water SW; it is only when the flows are entirely subcritical or entirely supercritical and when the obstacles are very
Nadiga, Balasubramanya T. "Balu"
Thermal Expansion Models of Viscous Fluids Based on Limits of Free Energy
Thermal Expansion Models of Viscous Fluids Based on Limits of Free Energy S.E. Bechtel Department March 25, 2002 Abstract Many viscous uid ows are mechanically incompressible, yet thermally expand associated with sound waves. The Boussi- nesq model for laboratory-scale, buoyancy-driven thermal convection
Aluffi, Paolo
Circular hydraulic jump in generalized-Newtonian fluids
We carry out an analytical study of laminar circular hydraulic jumps, in generalized-Newtonian fluids obeying the two-parametric power-law model of Ostwald-de Waele. Under the boundary-layer approximation we obtained exact expressions determining the flow, an implicit relation for the jump radius is derived. Corresponding results for Newtonian fluids can be retrieved as a limiting case for the flow behavior index n=1, predictions are made for fluids deviating from Newtonian behavior.
Rai, Ashutosh; Poria, Swarup
Simulations for Complex Fluid Flow Problems from Berkeley Lab's Center for Computational Sciences and Engineering (CCSE)
DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]
The Center for Computational Sciences and Engineering (CCSE) develops and applies advanced computational methodologies to solve large-scale scientific and engineering problems arising in the Department of Energy (DOE) mission areas involving energy, environmental, and industrial technology. The primary focus is in the application of structured-grid finite difference methods on adaptive grid hierarchies for compressible, incompressible, and low Mach number flows. The diverse range of scientific applications that drive the research typically involve a large range of spatial and temporal scales (e.g. turbulent reacting flows) and require the use of extremely large computing hardware, such as the 153,000-core computer, Hopper, at NERSC. The CCSE approach to these problems centers on the development and application of advanced algorithms that exploit known separations in scale; for many of the application areas this results in algorithms are several orders of magnitude more efficient than traditional simulation approaches.
E-Print Network 3.0 - air flow models Sample Search Results
Institute of Aeronautics and Astronautics Numerical Modeling of Doorway Flow Summary: software. The problem that was modeled is that of a flow from an air curtain mounted...
Isomorphic classical molecular dynamics model for an excess electronin a supercritical fluid
Ring polymer molecular dynamics (RPMD) is used to directly simulate the dynamics of an excess electron in a supercritical fluid over a broad range of densities. The accuracy of the RPMD model is tested against numerically exact path integral statistics through the use of analytical continuation techniques. At low fluid densities, the RPMD model substantially underestimates the contribution of delocalized states to the dynamics of the excess electron. However, with increasing solvent density, the RPMD model improves, nearly satisfying analytical continuation constraints at densities approaching those of typical liquids. In the high density regime, quantum dispersion substantially decreases the self-diffusion of the solvated electron. In this regime where the dynamics of the electron is strongly coupled to the dynamics of the atoms in the fluid, trajectories that can reveal diffusive motion of the electron are long in comparison to {beta}{h_bar}.
Miller III, Thomas F.
2D Thin-Film Flow of a Non-Newtonian Fluid Between Elastic Boundaries
.3.1 Power-law or Ostwald de Waele model ........................................................ 8 1.3.2 Ellis model .................................................................................................... 9 1.3.3 Carreau-Yasuda model... in different regimes of shear rates. The following constitutive models are relevant to this thesis. These do not consider the viscoelastic nature of polymeric liquids, which is outside the scope of this study. 8 1.3.1 Power-law or Ostwald de Waele...
Karri, Sunil
Isotropic singularities in shear-free perfect fluid cosmologies
We investigate barotropic perfect fluid cosmologies which admit an isotropic singularity. From the General Vorticity Result of Scott, it is known that these cosmologies must be irrotational. In this paper we prove, using two different methods, that if we make the additional assumption that the perfect fluid is shear-free, then the fluid flow must be geodesic. This then implies that the only shear-free, barotropic, perfect fluid cosmologies which admit an isotropic singularity are the FRW models.
Geoffery Ericksson; Susan M. Scott
Materials Science and Engineering B 117 (2005) 5361 Finite element analysis-based design of a fluid-flow control nano-valve
of a fluid-flow control nano-valve M. Grujicica,, G. Caoa, B. Pandurangana, W.N. Royb a Department A finite element method-based procedure is developed for the design of molecularly functionalized nano-size devices. The procedure is aimed at the single-walled carbon nano-tubes (SWCNTs) used in the construction
Grujicic, Mica
Extinction properties of single-walled carbon nanotubes: Two-fluid model
The extinction spectra of a single-walled carbon nanotube are investigated, within the framework of the vector wave function method in conjunction with the hydrodynamic model. Both polarizations of the incident plane wave (TE and TM with respect to the x-z plane) are treated. Electronic excitations on the nanotube surface are modeled by an infinitesimally thin layer of a two-dimensional electron gas represented by two interacting fluids, which takes into account the different nature of the ? and ? electrons. Numerical results show that strong interaction between the fluids gives rise to the splitting of the extinction spectra into two peaks in quantitative agreement with the ? and ? + ? plasmon energies.
Moradi, Afshin, E-mail: email@example.com [Department of Basic Sciences, Kermanshah University of Technology, Kermanshah, Iran and Department of Nano Science, Institute for Studies in Theoretical Physics and Mathematics (IPM), Tehran (Iran, Islamic Republic of)] [Department of Basic Sciences, Kermanshah University of Technology, Kermanshah, Iran and Department of Nano Science, Institute for Studies in Theoretical Physics and Mathematics (IPM), Tehran (Iran, Islamic Republic of)
Ion boundary conditions in semi-infinite fluid models of electron beam-plasma interaction
The modified Bohm criterion is derived for the plasma consisting of the monoenergetic electron beam and thermal electrons. This criterion allows us to define the accurate ion boundary conditions for semi-infinite collisionless fluid models of electron beam�plasma interaction. In the absence of electron beam, these boundary conditions give the classical sheath parameters. When the monoenergetic electron beam propagates through the plasma, the fluid model with proposed boundary conditions gives the results, which are in qualitative agreement with the results obtained earlier in M. Sharifian and B. Shokri, Phys. Plasmas 14, 093503 (2007). However, dynamics and parameters of the plasma sheath are different.
Levko, Dmitry [LAPLACE (Laboratoire Plasma et Conversion d'Energie), Universite de Toulouse, UPS, INPT Toulouse, 118 route de Narbonne, F-31062 Toulouse cedex 9 (France)
Fluid dynamics of rivulet flow between plates W. Drenckhan, H. Ritacco, A. Saint-Jalmes, A. Saugey, P. McGuinness, A. van der Net, D. Langevin, and D.
spaced, vertical glass plates. Such a "rivulet" is bounded by two liquid/solid and two mobile liquid/gas interfaces, posing fluid dynamic problems of direct relevance to local fluid flow in liquid foams/liquid or liquid/gas interfaces, as found in foams and emulsions, which respond to flow by adjusting their shape
CFD evaluation of pipeline gas stratification at low fluid flow due to temperature effects
variance in chord averaged velocities is apparent at these conditions. CFD analysis was performed. Low flow velocities of 0.1524 m/sec, 0.3048 m/sec and 0.6096 m/sec and temperature differences of 5.5 o K, 13.8 o K and 27.7 o K were considered. When... with gas velocity below 0.6096 m/sec. v DEDICATION To my family for their love and support. vi ACKNOWLEDGMENTS I would like to express my gratitude to Dr. Gerald Morrison for his valuable guidance and support. I...
Brar, Pardeep Singh
Equilibrium and volumetric data and model development of coal fluids
The long term goal of our efforts is to develop accurate predictive methods for description of equilibrium phase properties for a variety of types of mixtures and operating conditions. The specific objectives of the work specified herein include: (1) development of an experimental facility having the capability to provide data on equilibrium phase compositions (solubilities) and liquid densities, and doing so with greater accuracy and speed than our previous facility, (2) measurement of equilibrium phase properties for systematically-selected mixtures-specifically those containing important solute gases (such as hydrogen, carbon monoxide, methane, ethane, carbonyl sulfide, ammonia) in a series of heavy paraffinic, naphthenic and aromatic solvents (e.g., n-decane, n-eicosane, n-octacosane, n-hexatriacontane, cyclohexane, Decalin, perhydrophenanthrene, perhydropyrene, benzene, naphthalene, phenanthrene, pyrene), (3) testing/development of correlation frameworks for representing the phase behavior of fluids of the type encountered in coal conversion processes, and (4) generalization of parameters in the correlation frameworks to enable accurate predictions for systems of the type studied, permitting predictions to be made for systems and conditions other than those for which experimental data are available.
Robinson, R.L. Jr.; Gasem, K.A.M.; Park, J.
SHORT-TUBE SUBCRITICAL FLOW Enerag Division
#12;SHORT-TUBE SUBCRITICAL FLOW Y. C. Mei Enerag Division Oak Ridge National Laboratory Oak Ridge-tube subcritical flow. For short tubes used as refrigerant expansion devices, the orifice model is found inadequate-TUBE SUBCRITICAL FLOW INTRODUCTION Much theoretical and experimental work regarding short tube fluid flow has
Oak Ridge National Laboratory
A Numerical Algorithm for Single Phase Fluid Flow in Elastic Porous ...
Tong Sun. David P. Yale. Abstract. In this paper we consider an integrated model for ... blem has been built based on a finite element object library that we.
Fuzzy modelling of power system optimal load flow
In this paper, a fuzzy model for power system operation is presented. Uncertainties in loads and generations are modeled as fuzzy numbers. System behavior under known (while uncertain) injections is dealt with by a DC fuzzy power flow model. System optimal (while uncertain) operation is calculated with linear programming procedures where the problem nature and structure allows some efficient techniques such as Dantzig Wolfe decomposition and dual simplex to be used. Among the results, one obtains a fuzzy cost value for system operation and possibility distributions for branch power flows and power generations. Some risk analysis is possible, as system robustness and exposure indices can be derived and hedging policies can be investigated.
Miranda, V.; Saraiva, J.T. (FEUP, DEEC, Faculdade de Engenharia da Univ. do Porto, INESC, Inst. de Engenharia de Sistemas e Computadores, Lg de Mompilher 4000 Porto (PT))
A distributed converging overland flow model: 1. Mathematical solutions
MODEL The kinematic wave equations of continuity and momentum for a converging section are [Singh, 1974] 889 890 SHERMAN AND SINGH: FLOW MODELING, 1 X Fig. 1. Geometry of converging overland flow model. Oh O(uh) uh Ot q- Ox - q(x, t) q- L -- x (3...)' Q = uh = a(x,t)h n (4) where L is the length of the converging section (Figure 1). For a specified rainfall duration T, q(x, t) = 0 when t > T. We assume that n > 1. Eliminating u in (3) and (4), .we get Oh q_ na(x t)h \\"- Oh Ot ' Ox a(x, t...
Sherman, Bernard; Singh, Vijay P.
Phenomenological model for ordered onions under shear flow
We propose a phenomenological model for the multi-lamellar vesicles (onions) formation induced by shear flow. In a nonionic surfactant (C$_{12}$E$_4$) system, onion phases under a fixed shear flow within a certain range show the order-disorder transition accompanied with a size jump by changing temperature. Our model can simulate ordered and disordered onion phases with different onion sizes. We show numerical results of the onion formation simulated by the model and also discuss what factors in this system are critical to cause the transition between these two different onion phases.
Kenta Odagiri; Kazue Kudo
Cost and Performance Model for Redox Flow Batteries
A cost model was developed for all vanadium and iron-vanadium redox flow batteries. Electrochemical performance modeling was done to estimate stack performance at various power densities as a function of state of charge. This was supplemented with a shunt current model and a pumping loss model to estimate actual system efficiency. The operating parameters such as power density, flow rates and design parameters such as electrode aspect ratio, electrolyte flow channel dimensions were adjusted to maximize efficiency and minimize capital costs. Detailed cost estimates were obtained from various vendors to calculate cost estimates for present, realistic and optimistic scenarios. The main drivers for cost reduction for various chemistries were identified as a function of the energy to power ratio of the storage system. Levelized cost analysis further guided suitability of various chemistries for different applications.
Viswanathan, Vilayanur V.; Crawford, Aladsair J.; Stephenson, David E.; Kim, Soowhan; Wang, Wei; Li, Bin; Coffey, Greg W.; Thomsen, Edwin C.; Graff, Gordon L.; Balducci, Patrick J.; Kintner-Meyer, Michael CW; Sprenkle, Vincent L.
Wetting and free surface flow modeling for potting and encapsulation.
As part of an effort to reduce costs and improve quality control in encapsulation and potting processes the Technology Initiative Project ''Defect Free Manufacturing and Assembly'' has completed a computational modeling study of flows representative of those seen in these processes. Flow solutions are obtained using a coupled, finite-element-based, numerical method based on the GOMA/ARIA suite of Sandia flow solvers. The evolution of the free surface is solved with an advanced level set algorithm. This approach incorporates novel methods for representing surface tension and wetting forces that affect the evolution of the free surface. In addition, two commercially available codes, ProCAST and MOLDFLOW, are also used on geometries representing encapsulation processes at the Kansas City Plant. Visual observations of the flow in several geometries are recorded in the laboratory and compared to the models. Wetting properties for the materials in these experiments are measured using a unique flowthrough goniometer.
Brooks, Carlton, F.; Brooks, Michael J. (Los Alamos National Laboratory, Los Alamos, NM); Graham, Alan Lyman (Los Alamos National Laboratory, Los Alamos, NM); Noble, David F. (David Frederick) (.; )); Notz, Patrick K.; Hopkins, Matthew Morgan; Castaneda, Jaime N.; Mahoney, Leo James (Kansas City Plant, Kansas City, MO); Baer, Thomas A.; Berchtold, Kathryn (Los Alamos National Laboratory, Los Alamos, NM); Adolf, Douglas Brian; Wilkes, Edward Dean; Rao, Rekha Ranjana; Givler, Richard C.; Sun, Amy Cha-Tien; Cote, Raymond O.; Mondy, Lisa Ann; Grillet, Anne Mary; Kraynik, Andrew Michael
Fluid Heat Storage Systems in the Ground. Extraction ofof the storage aquifer lies 40 m below the ground surface,water storage. The influence of regional ground water flow
Doughty, Christine
Modeling of three-dimensional viscoelastic flows with free surfaces using a finite element method
A framework and code have been developed to simulate fiber and film processes; the code can handle three-dimensional, isothermal, incompressible, creeping flow of a Giesekus fluid with free surfaces at infinite capillary ...
Adrian, David Joseph
155: Numerical Models of Groundwater Flow and Transport
155: Numerical Models of Groundwater Flow and Transport EKKEHARD HOLZBECHER1 AND SHAUL SOREK2 1. #12;2402 GROUNDWATER Calibration as a task cannot be separated from the other tasks. Inverse modeling of the Negev, J. Blaustein Institutes for Desert Research, Sede Boker, Israel The article gives an introduction
Sorek, Shaul
Numerical Simulation of the Flow of a Power Law Fluid in an Elbow Bend
of shear ? is the power law index Hence the effective viscosity for a power law model is given by, ???? = ? ? ??? (??1) This is also known as the Ostwald-de Waele power law model and it has gained importance because of its simplicity. But, the main...
Kanakamedala, Karthik
Modeling and Algorithmic Approaches to Constitutively-Complex, Microstructured Fluids
We present a new multiscale model for complex uids based on three scales: microscopic, kinetic, and continuum. We choose the microscopic level as Kramers' bead-rod model for polymers, which we describe as a system of stochastic di#11;erential equations with an implicit constraint formulation. The associated Fokker-Planck equation is then derived, and adiabatic elimination removes the fast momentum coordinates. Approached in this way, the kinetic level reduces to a dispersive drift equation. The continuum level is modeled with a #12;nite volume Godunov-projection algorithm. We demonstrate computation of viscoelastic stress divergence using this multiscale approach.
Miller, Gregory H.; Forest, Gregory
Numerical modeling of multiphase plumes: a comparative study between two-fluid and mixed-fluid integral models
-field effects of a multiphase plume of liquid CO2 droplets in ocean water finds potential in estimating the environmental risks involved due to deep-ocean sequestration of greenhouse gases like carbon dioxide, which is one of the proposed alternatives (Liro... for the diffuser orifice diameter, air-flow rate and the number of such ports necessary to dissolve a measured quantity of air in a given time of operation will also be studied. 3.3. Case 3: CO2 Sequestration in the Ocean Sequestration of carbon dioxide and other...
Bhaumik, Tirtharaj
A numerical study of steady fluid flow in the entry region of a straight circular tube
region. The Basic Equations The flow under i nves ti gati on is governed by the Navier-Stokes equations p ? = F - . + uv Du Dt x ax p ? = F - @uv v, Dv a A 2 Dt y ay (2) Dw= F ma+ Dt w as and the continuity equation "u av aw + ? = p ay... + w D a a a a Ut = at ax ay as and 2 a2 a2 a2 ax2 ay2 as2 Expressed in cylindrical form, the previous equations become 2 P = Fr M + & v V r e D Ve 2aV Dt r " ar r2ae DVe V Ve 2aV V p + ? = Fe - ~a + u & Ve + r - e Dt r rae (2a) F -22+ pv V...
Crain, John Kee
Two dimensional, two fluid model for sodium boiling in LMFBR fuel assemblies
A two dimensional numerical model for the simulation of sodium boiling transient was developed using the two fluid set of conservation equations. A semiimplicit numerical differencing scheme capable of handling the problems associated with the ill-posedness implied by the complex characteristic roots of the two fluid problems was used, which took advantage of the dumping effect of the exchange terms. Of particular interest in the development of the model was the identification of the numerical problems caused by the strong disparity between the axial and radial dimensions of fuel assemblies. A solution to this problem was found which uses the particular geometry of fuel assemblies to accelerate the convergence of the iterative technique used in the model. Three sodium boiling experiments were simulated with the model, with good agreement between the experimental results and the model predictions.
Granziera, M.R.; Kazimi, M.S.
Investigation of combustive flows and dynamic meshing in computational fluid dynamics
of methane mass fraction contour plots using combustion model A. : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 70 21 Series of carbon monoxide mass fraction contour plots using com- bustion model A... in the domain. The unknowns are the dependent variables of the transport equations that must be solved. For example, if the transport equation is the species balance equation for carbon monoxide then the species mass fraction is the dependent variable...
Chambers, Steven B.
Characterizing Flow in Oil Reservoir Rock Using Smooth Particle Hydrodynamics
In this paper, a 3D Smooth Particle Hydrodynamics (SPH) simulator for modeling grain scale fluid flow in porous rock is presented. The versatility of the SPH method has driven its use in increasingly complex areas of flow ...
Holmes, David W.
Derivation and Implementation of Hybrid Fluid/Kinetic Model for Fusion Plasmas
This is a final report for Dr. Eric Held�s Junior Faculty in Plasmas Physics grant entitled, �Derivation and Implementation of Hybrid Fluid/Kinetic Model for Fusion Plasmas�. Progress over the three years and six months of this project included work on analytical and numerical fronts.
Held, E. D.
Experimental Validation of a Computational Fluid Dynamics Model for IAQ applications in Ice Rink Arenas
1 Experimental Validation of a Computational Fluid Dynamics Model for IAQ applications in Ice Rink, USA, Fax: 617-432-4122, Abstract Many ice rink arenas have ice resurfacing equipment that uses fossil temperature distributions in ice rinks. The numerical results agree reasonably with the corresponding
Towards a high order Fourier-SEM solver of fluid models in tokamaks
and energy expressed for both ions and elec- trons and on the assumption of quasi-neutrality of the plasma fluid (ions and electrons) numerical model. 1.1 Introduction The production of energy by fusion of light gradient and curvature effects. The ITER device is presently under construction in Cadarache (France) [17
Pasquetti, Richard
Numerical Modeling of Hydro-acoustic Waves In Weakly Compressible Fluid Ali Abdolali1,2
Numerical Modeling of Hydro-acoustic Waves In Weakly Compressible Fluid Ali Abdolali1,2 , James T of Civil Engineering, University of Roma Tre Low-frequency hydro-acoustic waves are precursors of tsunamis. Detection of hydro-acoustic waves generated due to the water column compression triggered by sudden seabed
Kirby, James T.
Control of surface gravity waves by variable fluid injection in a model of a copper
Control of surface gravity waves by variable fluid injection in a model of a copper converter splashing appears in copper converters when air is injected into the molten matte in order to carry out to the opposite extreme to where the nozzle injection is placed. Key words: Copper converter, gravity waves
Osses, Axel
Cavitation induced by explosion in an ideal fluid model Christophe Josserand*
Cavitation induced by explosion in an ideal fluid model Christophe Josserand* The James Franck a cavitation bubble for large enough energy. This gives a consistent view for rebound bubbles in superfluid.55.Bx, 67.55.Fa, 64.70.Fx I. INTRODUCTION Cavitation is a physical process involving such aspects
Fluid computation of the performanceenergy trade-off in large scale Markov models
total energy consumption should be chosen. H priority job SLA: 6.5s 90% L priority job SLA: 8s 80Fluid computation of the performanceenergy trade-off in large scale Markov models Anton Stefanek to deal with is that of running costs such as energy consumption versus the availability and re- sponse
Imperial College, London
Numerical modeling of an all vanadium redox flow battery.
We develop a capability to simulate reduction-oxidation (redox) flow batteries in the Sierra Multi-Mechanics code base. Specifically, we focus on all-vanadium redox flow batteries; however, the capability is general in implementation and could be adopted to other chemistries. The electrochemical and porous flow models follow those developed in the recent publication by [28]. We review the model implemented in this work and its assumptions, and we show several verification cases including a binary electrolyte, and a battery half-cell. Then, we compare our model implementation with the experimental results shown in [28], with good agreement seen. Next, a sensitivity study is conducted for the major model parameters, which is beneficial in targeting specific features of the redox flow cell for improvement. Lastly, we simulate a three-dimensional version of the flow cell to determine the impact of plenum channels on the performance of the cell. Such channels are frequently seen in experimental designs where the current collector plates are borrowed from fuel cell designs. These designs use a serpentine channel etched into a solid collector plate.
Clausen, Jonathan R.; Brunini, Victor E.; Moffat, Harry K.; Martinez, Mario J.
An Integrated Modeling Analysis of Unsaturated Flow Patterns in Fractured Rock
study, heat flow simulations use a 3-D thermal model grid (model grid, which is used for gas flow and ambient heat-flowgrid showing a smaller model domain, used for modeling gas and heat
Wu, Yu-Shu; Lu, Guoping; Zhang, Keni; Pan, Lehua; Bodvarsson, Gudmundur S.
Modelling Inter-Industry Material Flows
............................................................................................ 4 3.1.2. Life-cycle Analysis. The development of energy-materials-economic models arose out of the need for tools to aid the development, capable of representing complex systems and interactions in a comprehensive and concise way. However
One- and two-dimensional Stirling machine simulation using experimentally generated reversing flow turbuulence models
The activities described in this report do not constitute a continuum but rather a series of linked smaller investigations in the general area of one- and two-dimensional Stirling machine simulation. The initial impetus for these investigations was the development and construction of the Mechanical Engineering Test Rig (METR) under a grant awarded by NASA to Dr. Terry Simon at the Department of Mechanical Engineering, University of Minnesota. The purpose of the METR is to provide experimental data on oscillating turbulent flows in Stirling machine working fluid flow path components (heater, cooler, regenerator, etc.) with particular emphasis on laminar/turbulent flow transitions. Hence, the initial goals for the grant awarded by NASA were, broadly, to provide computer simulation backup for the design of the METR and to analyze the results produced. This was envisaged in two phases: First, to apply an existing one-dimensional Stirling machine simulation code to the METR and second, to adapt a two-dimensional fluid mechanics code which had been developed for simulating high Rayleigh number buoyant cavity flows to the METR. The key aspect of this latter component was the development of an appropriate turbulence model suitable for generalized application to Stirling simulation. A final-step was then to apply the two-dimensional code to an existing Stirling machine for which adequate experimental data exist. The work described herein was carried out over a period of three years on a part-time basis. Forty percent of the first year`s funding was provided as a match to the NASA funds by the Underground Space Center, University of Minnesota, which also made its computing facilities available to the project at no charge.
Goldberg, L.F. [Univ. of Minnesota, Minneapolis, MN (United States)
3rd International symposium on fluid flow measurement effects of acoustic noise on orifice meters
It is known that in-pipe acoustic noise can cause errors in orifice plate metering. The international metering community voted this topic as the highest priority for further research during a {open_quotes}working{close_quotes} held at N.T.I.S. in 1983. Most published work to date has been concerned with periodic, low frequency noise or pulsations, as encountered on reciprocating compressor installations where errors or their side effects may be readily noticed. Many orifice metering locations are, however, subject to high frequency noise emanating from control valves and centrifugal compressors. High frequency in-pipe noise is seldom suspected as a source of metering error and consequently it is a neglected topic. Square root error, which stems form the non-linear flow-differential pressure relationship of an orifice plate, has been well researched for low frequencies but the work has not been extended to high frequencies. To investigate this topic, high pressure studies at the British Gas Bishop Auckland Test Facility were carried out with a noise source (a pressure drop across a ball valve) and a 600 mm 0.4 {beta} orifice meter. These studies identified the effect of high frequency acoustic noise on orifice plate accuracy.
Norman, R.; Graham, P.; Drew, W.A. [Engineering Research Station, Newcastle Upon Tyne (United Kingdom)
Fundamentals of Engineering (FE) Exam Fluid Mechanics Review
Fundamentals of Engineering (FE) Exam Fluid Mechanics Review Steven Burian Civil & Environmental Engineering March 22, 2013 #12;Morning (Fluid Mechanics) A. Flow measurement B. Fluid properties C. Fluid, and compressors K. Non-Newtonian flow L. Flow through packed beds Fluids and FE #12;#12;#12;Fluids § Fluids
Provancher, William
Processes, mechanisms, parameters, and modeling approaches for partially saturated flow in soil and rock media; Yucca Mountain Site Characterization Project
This report discusses conceptual models and mathematical equations, analyzes distributions and correlations among hydrological parameters of soils and tuff, introduces new path integration approaches, and outlines scaling procedures to model potential-driven fluid flow in heterogeneous media. To properly model the transition from fracture-dominated flow under saturated conditions to matrix-dominated flow under partially saturated conditions, characteristic curves and permeability functions for fractures and matrix need to be improved and validated. Couplings from two-phase flow, heat transfer, solute transport, and rock deformation to liquid flow are also important. For stochastic modeling of alternating units of welded and nonwelded tuff or formations bounded by fault zones, correlations and constraints on average values of saturated permeability and air entry scaling factor between different units need to be imposed to avoid unlikely combinations of parameters and predictions. Large-scale simulations require efficient and verifiable numerical algorithms. New path integration approaches based on postulates of minimum work and mass conservation to solve flow geometry and potential distribution simultaneously are introduced. This verifiable integral approach, together with fractal scaling procedures to generate statistical realizations with parameter distribution, correlation, and scaling taken into account, can be used to quantify uncertainties and generate the cumulative distribution function for groundwater travel times.
Wang, J.S.Y.; Narasimhan, T.N. [Lawrence Berkeley Lab., CA (United States)
An investigation of a model of the flow pattern transition mechanism in relation to the identification of annular flow of R134a in a vertical tube using various void fraction models and flow regime maps
In the present study, new experimental data are presented for literature on the prediction of film thickness and identification of flow regime during the co-current downward condensation in a vertical smooth copper tube having an inner diameter of 8.1 mm and a length of 500 mm. R134a and water are used as working fluids in the tube side and annular side of a double tube heat exchanger, respectively. Condensation experiments are done at mass fluxes of 300 and 515 kg m{sup -2} s{sup -1}. The condensing temperatures are between 40 and 50 C; heat fluxes are between 12.65 and 66.61 kW m{sup -2}. The average experimental heat transfer coefficient of the refrigerant HFC-134a is calculated by applying an energy balance based on the energy transferred from the test section. A mathematical model by Barnea et al. based on the momentum balance of liquid and vapor phases is used to determine the condensation film thickness of R134a. The comparative film thickness values are determined indirectly using relevant measured data together with various void fraction models and correlations reported in the open literature. The effects of heat flux, mass flux, and condensation temperature on the film thickness and condensation heat transfer coefficient are also discussed for the laminar and turbulent flow conditions. There is a good agreement between the film thickness results obtained from the theoretical model and those obtained from six of 35 void fraction models in the high mass flux region of R134a. In spite of their different valid conditions, six well-known flow regime maps from the literature are found to be pred