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Note: This page contains sample records for the topic "fluid flow simulation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
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1

Fluid Flow Simulation in Fractured Reservoirs  

E-Print Network [OSTI]

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 ...

Sarkar, Sudipta

2002-01-01T23:59:59.000Z

2

MATHEMATICAL MODELING AND SIMULATION FOR FLUID FLOW IN POROUS MEDIA  

E-Print Network [OSTI]

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.

3

Numerical simulation of flow separation control by oscillatory fluid injection  

E-Print Network [OSTI]

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

2005-08-29T23:59:59.000Z

4

The simulation of free surface flows with Computational Fluid Dynamics B. Godderidge1  

E-Print Network [OSTI]

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

5

Numerical simulation of fluid flow in porous/fractured media  

SciTech Connect (OSTI)

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.

1981-01-01T23:59:59.000Z

6

Multiscale Modeling and Simulation of Fluid Flows in Inelastic Media  

E-Print Network [OSTI]

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

7

Multiscale Simulation Framework for Coupled Fluid Flow and Mechanical Deformation  

SciTech Connect (OSTI)

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

2014-11-14T23:59:59.000Z

8

Mathematical Modeling and Simulation for Applications of Fluid Flow in Porous Media \\Lambda  

E-Print Network [OSTI]

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

Ewing, Richard E.

9

3D MHD Free Surface Fluid Flow Simulation Based on Magnetic-Field Induction Equations  

E-Print Network [OSTI]

1 3D MHD Free Surface Fluid Flow Simulation Based on Magnetic-Field Induction Equations H.L. HUANG Huang@fusion.ucla.edu 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

10

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

2004-01-01T23:59:59.000Z

11

TOUGH Simulations of the Updegraff's Set of Fluid and Heat Flow Problems  

SciTech Connect (OSTI)

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.

1992-11-01T23:59:59.000Z

12

TOUGH2: A general-purpose numerical simulator for multiphase fluid and heat flow  

SciTech Connect (OSTI)

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.

1991-05-01T23:59:59.000Z

13

Fast and Informative Flow Simulations in a Building by Using Fast Fluid Dynamics Model on Graphics Processing Unit  

E-Print Network [OSTI]

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"

14

Modeling fluid flow through single fracture using experimental, stochastic, and simulation approaches  

E-Print Network [OSTI]

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

2004-09-30T23:59:59.000Z

15

A splitting method for numerical simulation of free surface flows of incompressible fluids with surface tension  

E-Print Network [OSTI]

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.

16

Theoretical and Numerical Simulation of Non-Newtonian Fluid Flow in Propped Fractures  

E-Print Network [OSTI]

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

2013-12-10T23:59:59.000Z

17

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

2014-08-06T23:59:59.000Z

18

Status of the TOUGH-FLAC simulator and recent applications related to coupled fluid flow and crustal deformations  

SciTech Connect (OSTI)

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.

2010-06-01T23:59:59.000Z

19

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.

20

Computational fluid dynamics simulation of the air/suppressant flow in an uncluttered F18 engine nacelle  

SciTech Connect (OSTI)

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.

1997-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "fluid flow simulation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

A Robust Four-Fluid Transient Flow Simulator as an Analysis and Decision Making Tool for Dynamic Kill Operation  

E-Print Network [OSTI]

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

2013-04-24T23:59:59.000Z

22

FRACSTIM/I: A Fully Coupled Fluid Flow/Heat Transport and Geomechanica...  

Broader source: Energy.gov (indexed) [DOE]

FRACSTIMI: A Fully Coupled Fluid FlowHeat Transport and Geomechanical DeformationFracture Generation Simulator FRACSTIMI: A Fully Coupled Fluid FlowHeat Transport and...

23

Multiphase flow and Encapsulation simulations using the moment of fluid method 1  

E-Print Network [OSTI]

, 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

24

PROBABILISTIC SIMULATION OF SUBSURFACE FLUID FLOW: A STUDY USING A NUMERICAL SCHEME  

SciTech Connect (OSTI)

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

1980-03-01T23:59:59.000Z

25

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.

1993-11-30T23:59:59.000Z

26

Fluid flow monitoring device  

DOE Patents [OSTI]

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)

1993-01-01T23:59:59.000Z

27

Numerical simulation of flow of shear-thinning fluids in corrugated channels  

E-Print Network [OSTI]

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

2009-05-15T23:59:59.000Z

28

Numerical simulation of flow of shear-thinning fluids in corrugated channels  

E-Print Network [OSTI]

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

2008-10-10T23:59:59.000Z

29

Multiscale Simulations for Polymeric Flow  

E-Print Network [OSTI]

Multiscale simulation methods have been developed based on the local stress sampling strategy and applied to three flow problems with different difficulty levels: (a) general flow problems of simple fluids, (b) parallel (one-dimensional) flow problems of polymeric liquids, and (c) general (two- or three-dimensional) flow problems of polymeric liquids. In our multiscale methods, the local stress of each fluid element is calculated directly by performing microscopic or mesoscopic simulations according to the local flow quantities instead of using any constitutive relations. For simple fluids (a), such as the Lenard-Jones liquid, a multiscale method combining MD and CFD simulations is developed based on the local equilibrium assumption without memories of the flow history. (b), the multiscale method is extended to take into account the memory effects that arise in hydrodynamic stress due to the slow relaxation of polymer-chain conformations. The memory of polymer dynamics on each fluid element is thus resolved by performing MD simulations in which cells are fixed at the mesh nodes of the CFD simulations.For general (two- or three-dimensional) flow problems of polymeric liquids (c), it is necessary to trace the history of microscopic information such as polymer-chain conformation, which carries the memories of past flow history, along the streamline of each fluid element. A Lagrangian-based CFD is thus implemented to correctly advect the polymer-chain conformation consistently with the flow. On each fluid element, coarse-grained polymer simulations are carried out to consider the dynamics of entangled polymer chains that show extremely slow relaxation compared to microscopic time scales.

Takahiro Murashima; Takashi Taniguchi; Ryoichi Yamamoto; Shugo Yasuda

2011-01-06T23:59:59.000Z

30

High-Performance Reactive Fluid Flow Simulations Using Adaptive Mesh Refinement on Thousands of Processors  

E-Print Network [OSTI]

Thermonuclear Flashes at the University of Chicago. FLASH is a modular, adaptive mesh, parallel simulation code to thermonuclear reactions in supernovae and novae. The FLASH code was designed to study thermonuclear flashes Thermonuclear Flashes, The University of Chicago, Chicago, IL 60637 2 Center for Applied Scientific Computing

Rhoads, James

31

Insertable fluid flow passage bridgepiece and method  

DOE Patents [OSTI]

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)

2000-01-01T23:59:59.000Z

32

Simulating Fluids Exhibiting Microstructure  

E-Print Network [OSTI]

... fluids containing elastic particles, and polymer fluids, all exhibit non-trivial macroscopic behavior due to interactions occurring on micro/mesoscopic scales.

33

Non-Newtonian fluid flow  

E-Print Network [OSTI]

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

1963-01-01T23:59:59.000Z

34

Fluid Gravity Engineering Rocket motor flow analysis  

E-Print Network [OSTI]

Fluid Gravity Engineering Capability · Rocket motor flow analysis -Internal (performance) -External young scientists/engineers Fluid Gravity Engineering Ltd #12;

Anand, Mahesh

35

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.

36

SEISMIC MONITORING OF CARBON DIOXIDE FLUID FLOW  

E-Print Network [OSTI]

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

37

Finite element simulation of electrorheological fluids  

E-Print Network [OSTI]

Electrorheological (ER) fluids change their flow properties dramatically when an electric field is applied. These fluids are usually composed of dispersions of polarizable particles in an insulating base fluid or composed ...

Rhyou, Chanryeol, 1973-

2005-01-01T23:59:59.000Z

38

DEVELOPMENT OF PIV TECHNIQUE UNDER MAGNETIC FIELDS AND MEASUREMENT OF TURBULENT PIPE FLOW OF FLIBE SIMULANT FLUID  

E-Print Network [OSTI]

sufficiently large heat transfer using high Prandtl number fluid coolant, high turbulence is required, and the heat transfer characteristics of low Prandtl number fluids are con heat transfer (low film temperature drop) to cool first wall structures. In order to obtain

Abdou, Mohamed

39

Process for retarding fluid flow  

SciTech Connect (OSTI)

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.

1989-01-10T23:59:59.000Z

40

Friction-Induced Fluid Heating in Nanoscale Helium Flows  

SciTech Connect (OSTI)

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)

2010-05-21T23:59:59.000Z

Note: This page contains sample records for the topic "fluid flow simulation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

SEISMIC MONITORING OF CARBON DIOXIDE FLUID FLOW  

E-Print Network [OSTI]

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.

santos

42

A Parallel Implementation of the TOUGH2 Software Package for Large Scale Multiphase Fluid and Heat Flow Simulations  

E-Print Network [OSTI]

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

43

A Parallel Implementation of the TOUGH2 Software Package for Large Scale Multiphase Fluid and Heat Flow Simulations  

E-Print Network [OSTI]

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

Elmroth, Erik

44

FRACSTIM/I: A Fully Coupled Fluid Flow/Heat Transport and Geomechanica...  

Broader source: Energy.gov (indexed) [DOE]

FRACSTIMI: A Fully Coupled Fluid FlowHeat Transport and Geomechanical DeformationFracture Generation Simulator aka FALCON: Fracturing and Liquid CONservation Robert K....

45

USERS GUIDE of TOUGH2-EGS-MP: A Massively Parallel Simulator with Coupled Geomechanics for Fluid and Heat Flow in Enhanced Geothermal Systems VERSION 1.0  

SciTech Connect (OSTI)

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

2013-12-01T23:59:59.000Z

46

Low Speed Virtual Wind Tunnel Simulation For Educational Studies In Introducing Computational Fluid Dynamics And Flow Visualization  

E-Print Network [OSTI]

............................................................................................................... 25 3.2.4. Starting FlowLab ...................................................................................................................... 26 3.2.5. Geometry Settings... OF THE PROGRAMMING....................................................................... 52 v List of Figures FIGURE 2.1 ? COST AND TIME RELATIONSHIP WITH RESPECT TO CFD AND WIND TUNNELS............................. 5 FIGURE 2.2 - BOEING 777 DESIGN...

Yang, Cher-Chiang

2008-05-05T23:59:59.000Z

47

Simulation of fluid flow mechanisms in high permeability zones (Super-K) in a giant naturally fractured carbonate reservoir  

E-Print Network [OSTI]

and fractures were treated as two systems. Reservoir management practices and decisions should be very carefully reviewed and executed in this dual continuum reservoir based on the results of this work. Studying this dual media flow behavior is vital for better...

Abu-Hassoun, Amer H.

2009-05-15T23:59:59.000Z

48

FRACSTIM/I: A Fully Coupled Fluid Flow/Heat Transport and Geomechanical Deformation/Fracture Generation Simulator  

Broader source: Energy.gov [DOE]

This research will develop a fully coupled, fully implicit approach for EGS stimulation and reservoir simulation. Solve all governing equations simultaneously in fully implicit way. Enable massively parallel performance and scalability. Apply state of the art nonlinear PDE solvers: Jacobian Free Newton Krylov (JFNK) method.

49

Application of Neutron Imaging and Scattering to Fluid Flow and...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

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...

50

Fracture Network and Fluid Flow Imaging for EGS Applications...  

Broader source: Energy.gov (indexed) [DOE]

Fracture Network and Fluid Flow Imaging for EGS Applications from Multi-Dimensional Electrical Resistivity Structure Fracture Network and Fluid Flow Imaging for EGS Applications...

51

FLUID MECHANICS AND HEAT TRANSFER OF ELECTRON FLOW IN SEMICONDUCTORS  

E-Print Network [OSTI]

= 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

52

Fluid flow control with transformation media  

E-Print Network [OSTI]

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

2011-01-01T23:59:59.000Z

53

Directed flow fluid rinse trough  

DOE Patents [OSTI]

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)

1996-01-01T23:59:59.000Z

54

Directed flow fluid rinse trough  

DOE Patents [OSTI]

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.

1996-07-02T23:59:59.000Z

55

The incorporation of bubbles into a computer graphics fluid simulation  

E-Print Network [OSTI]

We present methods for incorporating bubbles into a photorealistc fluid simulation. Previous methods of fluid simulation in computer graphics do not include bubbles. Our system automatically creates bubbles, which are simulated on top of the fluid...

Greenwood, Shannon Thomas

2005-08-29T23:59:59.000Z

56

Method and apparatus for controlling fluid flow  

DOE Patents [OSTI]

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.

1980-06-27T23:59:59.000Z

57

Newtonian fluid flow through Microfabricated Hyperbolic Contractions  

E-Print Network [OSTI]

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

58

Momentum spectra, anisotropic flow, and ideal fluids  

E-Print Network [OSTI]

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

2006-07-28T23:59:59.000Z

59

Separation of particles from gaseous fluid flows  

SciTech Connect (OSTI)

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.

1980-12-16T23:59:59.000Z

60

Visually simulating realistic fluid motion  

E-Print Network [OSTI]

's second law of motion and Conservation of Mass, which leads to the continuity equation. Newton's second law states that the total force F, acting on an element equals mass m times the element's acceleration a. In the case of fluids we do not consider...

Naithani, Priyanka

2002-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "fluid flow simulation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Ultrasonic fluid flow measurement method and apparatus  

DOE Patents [OSTI]

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)

1993-01-01T23:59:59.000Z

62

Ultrasonic fluid flow measurement method and apparatus  

DOE Patents [OSTI]

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.

1993-10-12T23:59:59.000Z

63

Numerical simulation of the fluid flow and heat transfer processes during scavenging in a two-stroke engine under steady-state conditions  

SciTech Connect (OSTI)

A numerical simulation of the scavenging process in a two-stroke flat-piston model engine has been developed. Air enters the cylinder circumferentially, inducting a three-dimensional turbulent swirling flow. The problem was modeled as a steady-state axisymmetric flow through a cylinder with uniform wall temperature. The steady-state regime was simulated by assuming the piston head fixed at the bottom dead center. The calculation was performed employing the {kappa}-{epsilon} model of turbulence. A comparison of the results obtained for the flow field with available experimental data showed very good agreement, and a comparison with an available numerical solution revealed superior results. The effects of the Reynolds number, inlet port angles, and engine geometry on the flow and in-cylinder heat transfer characteristics were investigated. The Nusselt number substantially increases with larger Reynolds numbers and a smaller bore-to-stroke ratio. It is shown that the positioning of the exhaust value(s) is the main parameter to control the scavenging process.

Castro Gouveia, M. de; Reis Parise, J.A. dos; Nieckele, A.O. (Pontificia Univ. Catolica, Rio de Janeiro (Brazil))

1992-05-01T23:59:59.000Z

64

MODELING COUPLED FLUID FLOW AND GEOMECHANICAL AND GEOPHYSICAL PHENOMENA WITHIN  

E-Print Network [OSTI]

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

65

Computational fluid dynamics assessment: Volume 1, Computer simulations of the METC (Morgantown Energy Technology Center) entrained-flow gasifier: Final report  

SciTech Connect (OSTI)

An assessment of the theoretical and numerical aspects of the computer code, PCGC-2, is made; and the results of the application of this code to the Morgantown Energy Technology Center (METC) advanced gasification facility entrained-flow reactor, ''the gasifier,'' are presented. PCGC-2 is a code suitable for simulating pulverized coal combustion or gasification under axisymmetric (two-dimensional) flow conditions. The governing equations for the gas and particulate phase have been reviewed. The numerical procedure and the related programming difficulties have been elucidated. A single-particle model similar to the one used in PCGC-2 has been developed, programmed, and applied to some simple situations in order to gain insight to the physics of coal particle heat-up, devolatilization, and char oxidation processes. PCGC-2 was applied to the METC entrained-flow gasifier to study numerically the flash pyrolysis of coal, and gasification of coal with steam or carbon dioxide. The results from the simulations are compared with measurements. The gas and particle residence times, particle temperature, and mass component history were also calculated and the results were analyzed. The results provide useful information for understanding the fundamentals of coal gasification and for assessment of experimental results performed using the reactor considered. 69 refs., 35 figs., 23 tabs.

Celik, I.; Chattree, M.

1988-07-01T23:59:59.000Z

66

Three-Dimensional Characteristics of Post-CHF Behaviour Within a Rod Bundle for Loss-of-Flow Simulation: Experimental and Three-Fluid Porous Media Numerical Analyses  

SciTech Connect (OSTI)

The investigation of three-dimensional transient propagations of dry-out fronts within a nuclear fuel rod bundle is performed, based on experimental and numerical simulations. The spreading of Critical Heat Flux (CHF) fronts across a bundle, caused by sudden decrease of coolant mass flow rate followed by delayed gradual decrease of power generation is predicted, and the locus of dry patches is shown. Simultaneous occurrence of CHF and re-wet multi-fronts in here-analysed flow transient has not been detected so obvious as in power transient, previously analysed. Due to a possible building of a vapour zone, the CHF front spatial propagation has to be carefully analysed in transient conditions. (authors)

Stosic, Zoran V. [Framatome ANP GmbH, PO Box 3220, Erlangen, 91050 (Germany); Stevanovic, Vladimir D. [University of Belgrade, Kraljice Marije 16, 11000 Belgrade, Serbia and Montenegro (Yugoslavia); Tadashi Iguchi [Japan Atomic Energy Research Institute, Tokai-mura 319-1195 (Japan)

2002-07-01T23:59:59.000Z

67

Supercritical Fluid Extraction- Process Simulation and Design  

E-Print Network [OSTI]

SIMULATION P-1 SFE FEED PUMP SUPERCRITICAL FLUID EXTRACTOR (SFE) 2 T-1 10 7 .r D-2 SFE BOnoMS FLASH 9 222 The extract is decanted and fed to the fractionator to recover solvent carbon dioxide overhead and waterlIPA/carbon dioxide out...

Martin, C. L.; Seibert, A. F.

68

Geomechanical Simulation of Fluid-Driven Fractures  

SciTech Connect (OSTI)

The project supported graduate students working on experimental and numerical modeling of rock fracture, with the following objectives: (a) perform laboratory testing of fluid-saturated rock; (b) develop predictive models for simulation of fracture; and (c) establish educational frameworks for geologic sequestration issues related to rock fracture. These objectives were achieved through (i) using a novel apparatus to produce faulting in a fluid-saturated rock; (ii) modeling fracture with a boundary element method; and (iii) developing curricula for training geoengineers in experimental mechanics, numerical modeling of fracture, and poroelasticity.

Makhnenko, R.; Nikolskiy, D.; Mogilevskaya, S.; Labuz, J.

2012-11-30T23:59:59.000Z

69

Simulation of Biological Flow and Transport in Complex Geometries using Embedded Boundary /  

E-Print Network [OSTI]

Simulation of Biological Flow and Transport in Complex Geometries using Embedded Boundary / Volume for modeling polymer fluids in irregular microscale geometries that enables long-time simulation of validation the constitutive behavior of polymer fluids. Complex flow environment geometries are represented on Cartesian grids

70

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...

71

Use of Geophysical Techniques to Characterize Fluid Flow in a...  

Broader source: Energy.gov (indexed) [DOE]

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...

72

Fracture Network and Fluid Flow Imaging for EGS Applications...  

Broader source: Energy.gov (indexed) [DOE]

Fracture Network and Fluid Flow Imaging for EGS Applications from Multi-Dimensional Electrical Resistivity Structure Principal Investigator: Philip E. Wannamaker University of Utah...

73

Fracture Network and Fluid Flow Imaging for EGS Applications...  

Broader source: Energy.gov (indexed) [DOE]

Network and Fluid Flow Imaging for EGS Applications from Multi-Dimensional Electrical Resistivity Structure Principal Investigator: Philip E. Wannamaker University of Utah Energy &...

74

Use of Geophysical Techniques to Characterize Fluid Flow in a...  

Broader source: Energy.gov (indexed) [DOE]

and test combined geophysical techniques to characterize fluid flow, in relation to fracture orientations and fault distributions in a geothermal system. Average Overall Score:...

75

Dispersed Fluid Flow in Fractured Reservoirs- an Analysis of...  

Open Energy Info (EERE)

correlations. Downhole measurements of the tracer response exiting from discrete fracture zones permit further characterization of reservoir fluid flow behavior. Tracer...

76

1. Introduction Fluid flow in continuous casting of steel is of great inter-  

E-Print Network [OSTI]

-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.

77

Journal of Fluids and Structures 24 (2008) 250269 Numerical and experimental study of expiratory flow  

E-Print Network [OSTI]

, 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

2008-01-01T23:59:59.000Z

78

Device for deriving energy from a flow of fluid  

SciTech Connect (OSTI)

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.

1982-12-07T23:59:59.000Z

79

Statistical mechanical theory for steady-state systems. III. Heat flow in a Lennard-Jones fluid  

E-Print Network [OSTI]

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

80

Advanced tomographic flow diagnostics for opaque multiphase fluids  

SciTech Connect (OSTI)

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.

1997-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "fluid flow simulation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Method and apparatus for chemically altering fluids in continuous flow  

DOE Patents [OSTI]

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)

1993-01-01T23:59:59.000Z

82

Method and apparatus for chemically altering fluids in continuous flow  

DOE Patents [OSTI]

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.

1993-10-19T23:59:59.000Z

83

Computational Fluid Dynamics Simulation of Fluidized Bed Polymerization Reactors  

SciTech Connect (OSTI)

Fluidized beds (FB) reactors are widely used in the polymerization industry due to their superior heat- and mass-transfer characteristics. Nevertheless, problems associated with local overheating of polymer particles and excessive agglomeration leading to FB reactors defluidization still persist and limit the range of operating temperatures that can be safely achieved in plant-scale reactors. Many people have been worked on the modeling of FB polymerization reactors, and quite a few models are available in the open literature, such as the well-mixed model developed by McAuley, Talbot, and Harris (1994), the constant bubble size model (Choi and Ray, 1985) and the heterogeneous three phase model (Fernandes and Lona, 2002). Most these research works focus on the kinetic aspects, but from industrial viewpoint, the behavior of FB reactors should be modeled by considering the particle and fluid dynamics in the reactor. Computational fluid dynamics (CFD) is a powerful tool for understanding the effect of fluid dynamics on chemical reactor performance. For single-phase flows, CFD models for turbulent reacting flows are now well understood and routinely applied to investigate complex flows with detailed chemistry. For multiphase flows, the state-of-the-art in CFD models is changing rapidly and it is now possible to predict reasonably well the flow characteristics of gas-solid FB reactors with mono-dispersed, non-cohesive solids. This thesis is organized into seven chapters. In Chapter 2, an overview of fluidized bed polymerization reactors is given, and a simplified two-site kinetic mechanism are discussed. Some basic theories used in our work are given in detail in Chapter 3. First, the governing equations and other constitutive equations for the multi-fluid model are summarized, and the kinetic theory for describing the solid stress tensor is discussed. The detailed derivation of DQMOM for the population balance equation is given as the second section. In this section, monovariate population balance, bivariate population balance, aggregation and breakage equation and DQMOM-Multi-Fluid model are described. In the last section of Chapter 3, numerical methods involved in the multi-fluid model and time-splitting method are presented. Chapter 4 is based on a paper about application of DQMOM to polydisperse gas-solid fluidized beds. Results for a constant aggregation and breakage kernel and a kernel developed from kinetic theory are shown. The effect of the aggregation success factor and the fragment distribution function are investigated. Chapter 5 shows the work on validation of mixing and segregation phenomena in gas-solid fluidized beds with a binary mixture or a continuous size distribution. The simulation results are compared with available experiment data and discrete-particle simulation. Chapter 6 presents the project with Univation Technologies on CFD simulation of a Polyethylene pilot-scale FB reactor, The fluid dynamics, mass/heat transfer and particle size distribution are investigated through CFD simulation and validated with available experimental data. The conclusions of this study and future work are discussed in Chapter 7.

Rong Fan

2006-08-09T23:59:59.000Z

84

Shear-slip analysis in multiphase fluid-flow reservoir engineering ap plications using TOUGH-FLAC  

E-Print Network [OSTI]

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

2008-01-01T23:59:59.000Z

85

Imaging Fluid Flow in Geothermal Wells Using Distributed Thermal Perturbation Sensing  

E-Print Network [OSTI]

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.

2011-01-01T23:59:59.000Z

86

On fluid flow in a heterogeneous medium under nonisothermal conditions  

SciTech Connect (OSTI)

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

2010-11-01T23:59:59.000Z

87

Numerical simulation of the air flow field in a laboratory fume hood using the CFD-ACE(TM) computational fluid dynamics code  

E-Print Network [OSTI]

realized information on the hood entry losses and other design parameters that are of interest to the users, designers and owners of fume hoods. After the specification of the problem and generation of the mesh, the modeled hood was simulated using CFD...

D'Sousa, Cedric Benedict

1997-01-01T23:59:59.000Z

88

Feedback regulated induction heater for a flowing fluid  

DOE Patents [OSTI]

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.

1984-06-13T23:59:59.000Z

89

Feedback regulated induction heater for a flowing fluid  

DOE Patents [OSTI]

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)

1985-01-01T23:59:59.000Z

90

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...

91

Investigation of Swirling Flow in Rod Bundle Subchannels Using Computational Fluid Dynamics  

SciTech Connect (OSTI)

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)

2006-07-01T23:59:59.000Z

92

Advanced computational simulation of flow phenomena associated with orifice meters  

SciTech Connect (OSTI)

This paper presents and discusses results from a series of computational fluid dynamics (CFD) simulations of fluid flow phenomena associated with orifice meters. These simulations were performed using a new, state-of-the-art CFD code developed at Southwest Research Institute. This code is based on new techniques designed to take advantage of parallel computers to increase computational performance and fidelity of simulation results. This algorithm uses a domain decomposition strategy to create grid systems for very complex geometries composed of simpler geometric subregions, allowing for the accurate representation of the fluid flow domain. The domain decomposition technique maps naturally to parallel computer architectures. Here, the concept of message-passing is used to create a parallel algorithm, using the Parallel Virtual Machine (PVM) library. This code is then used to simulate the flow through an orifice meter run consisting of an orifice with a beta ratio of 0.5 and air flowing at a Reynolds number of 91,100. The work discussed in this paper is but the first step in developing a Virtual Metering Research Facility to support research, analysis, and formulation of new standards for metering.

Freitas, C.J. [Southwest Research Inst., San Antonio, TX (United States)

1995-12-31T23:59:59.000Z

93

On the acceleration potential in perfect fluid flow  

E-Print Network [OSTI]

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

1960-01-01T23:59:59.000Z

94

CIRQ: Qualitative fluid flow modelling for aerospace FMEA applications Neal Snooke  

E-Print Network [OSTI]

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

95

Numerical simulation of electrokinetically driven micro flows  

E-Print Network [OSTI]

Spectral element based numerical solvers are developed to simulate electrokinetically driven flows for micro-fluidic applications. Based on these numerical solvers, basic phenomena and devices for electrokinetic applications in micro and nano flows...

Hahm, Jungyoon

2005-11-01T23:59:59.000Z

96

Phenomenology and simulations of active fluids  

E-Print Network [OSTI]

Active fluids are an interesting new class of non-equilibrium systems in physics. In such fluids, the system is forced out of equilibrium by the individual active particles - in contrast to driven systems where the system ...

Tjhung, Elsen

2013-11-28T23:59:59.000Z

97

System and method measuring fluid flow in a conduit  

DOE Patents [OSTI]

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)

1999-01-01T23:59:59.000Z

98

Flows of Incompressible Newtonian and Generalized Newtonian Fluids over a Circular Cylinder  

E-Print Network [OSTI]

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

2012-05-31T23:59:59.000Z

99

Calculation of unsteady turbulent flow around obstacles using the large eddy simulation turbulence model  

E-Print Network [OSTI]

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

2002-01-01T23:59:59.000Z

100

PAPER B3: PHYSICS OF FLUID FLOWS Hilary Term 2010  

E-Print Network [OSTI]

,...) · 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.

Note: This page contains sample records for the topic "fluid flow simulation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

The Flow of Newtonian Fluids in Axisymmetric Corrugated Tubes  

E-Print Network [OSTI]

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.

Taha Sochi

2010-06-08T23:59:59.000Z

102

Phase-field simulations of viscous fingering in shear-thinning fluids  

E-Print Network [OSTI]

A phase-field model for the Hele-Shaw flow of non-Newtonian fluids is developed. It extends a previous model for Newtonian fluids to a wide range of shear-dependent fluids. The model is applied to perform simulations of viscous fingering in shear- thinning fluids, and it is found to be capable of describing the complete crossover from the Newtonian regime at low shear rate to the strongly shear-thinning regime at high shear rate. The width selection of a single steady-state finger is studied in detail for a 2-plateaux shear-thinning law (Carreau law) in both its weakly and strongly shear-thinning limits, and the results are related to previous analyses. In the strongly shear-thinning regime a rescaling is found for power-law (Ostwald-de-Waehle) fluids that allows for a direct comparison between simulations and experiments without any adjustable parameters, and good agreement is obtained.

Sebastien Nguyen; Roger Folch; Vijay K. Verma; Herv Henry; Mathis Plapp

2009-12-01T23:59:59.000Z

103

Characterization of fracture networks for fluid flow analysis  

SciTech Connect (OSTI)

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.

1989-06-01T23:59:59.000Z

104

Criteria for shear banding in time-dependent flows of complex fluids  

E-Print Network [OSTI]

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

2013-01-21T23:59:59.000Z

105

Numeric Simulation of Heat Transfer and Electrokinetic Flow in an Electroosmosis-Based  

E-Print Network [OSTI]

Numeric Simulation of Heat Transfer and Electrokinetic Flow in an Electroosmosis-Based Continuous is dedicated to under- standing the fluid flow and heat transfer mechanisms occurring in continuous flow PCR are discussed in detail. The importance of each heat transfer mechanism for different situations is also

Le Roy, Robert J.

106

MPSalsa 3D Simulations of Chemically Reacting Flows  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

Many important scientific and engineering applications require a detailed analysis of complex systems with coupled fluid flow, thermal energy transfer, mass transfer and nonequilibrium chemical reactions. Currently, computer simulations of these complex reacting flow problems are limited to idealized systems in one or two spatial dimensions when coupled with a detailed, fundamental chemistry model. The goal of our research is to develop, analyze and implement advanced MP numerical algorithms that will allow high resolution 3D simulations with an equal emphasis on fluid flow and chemical kinetics modeling. In our research, we focus on the development of new, fully coupled, implicit solution strategies that are based on robust MP iterative solution methods (copied from http://www.cs.sandia.gov/CRF/MPSalsa/). These simulations are needed for scientific and technical areas such as: combustion research for transportation, atmospheric chemistry modeling for pollution studies, chemically reacting flow models for analysis and control of manufacturing processes, surface catalytic reactors for methane to methanol conversion and chemical vapor deposition (CVD) process modeling for production of advanced semiconductor materials (http://www.cs.sandia.gov/CRF/MPSalsa/).

This project website provides six QuickTime videos of these simulations, along with a small image gallery and slideshow animations. A list of related publications and conference presentations is also made available.

107

Multiphase fluid flow and time lapse seismics  

E-Print Network [OSTI]

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...

santos

108

Electromagnetic Radiations as a Fluid Flow  

E-Print Network [OSTI]

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

2009-11-25T23:59:59.000Z

109

Notes 10. A thermohydrodynamic bulk-flow model for fluid film bearings  

E-Print Network [OSTI]

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

2009-01-01T23:59:59.000Z

110

Flow of fractal fluid in pipes: Non-integer dimensional space Vasily E. Tarasov  

E-Print Network [OSTI]

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.

111

Two-Phase Fluid-Solid Flow Name of Supervisor: Dr D. Harris  

E-Print Network [OSTI]

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

112

Measurement Of The Fluid Flow Load On A Globe Valve Stem Under Various Cavitation  

E-Print Network [OSTI]

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

Paris-Sud XI, Université de

113

Production of Natural Gas and Fluid Flow in Tight Sand Reservoirs  

SciTech Connect (OSTI)

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

2006-06-30T23:59:59.000Z

114

Robust processing of optical flow of fluids Ashish Doshi and Adrian G. Bors, Senior Member, IEEE  

E-Print Network [OSTI]

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

115

Molecular dynamics simulations of oscillatory Couette flows with slip boundary conditions  

E-Print Network [OSTI]

The effect of interfacial slip on steady-state and time-periodic flows of monatomic liquids is investigated using non-equilibrium molecular dynamics simulations. The fluid phase is confined between atomically smooth rigid walls, and the fluid flows are induced by moving one of the walls. In steady shear flows, the slip length increases almost linearly with shear rate. We found that the velocity profiles in oscillatory flows are well described by the Stokes flow solution with the slip length that depends on the local shear rate. Interestingly, the rate dependence of the slip length obtained in steady shear flows is recovered when the slip length in oscillatory flows is plotted as a function of the local shear rate magnitude. For both types of flows, the friction coefficient at the liquid-solid interface correlates well with the structure of the first fluid layer near the solid wall.

Nikolai V. Priezjev

2012-08-27T23:59:59.000Z

116

Radiation Modeling In Fluid Flow Iain D. Boyd  

E-Print Network [OSTI]

· 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

117

Assembly flow simulation of a radar  

SciTech Connect (OSTI)

A discrete event simulation model has been developed to predict the assembly flow time of a new radar product. The simulation was the key tool employed to identify flow constraints. The radar, production facility, and equipment complement were designed, arranged, and selected to provide the most manufacturable assembly possible. A goal was to reduce the assembly and testing cycle time from twenty-six weeks to six weeks. A computer software simulation package (SLAM II) was utilized as the foundation a for simulating the assembly flow time. FORTRAN subroutines were incorporated into the software to deal with unique flow circumstances that were not accommodated by the software. Detailed information relating to the assembly operations was provided by a team selected from the engineering, manufacturing management, inspection, and production assembly staff. The simulation verified that it would be possible to achieve the cycle time goal of six weeks. Equipment and manpower constraints were identified during the simulation process and adjusted as required to achieve the flow with a given monthly production requirement. The simulation is being maintained as a planning tool to be used to identify constraints in the event that monthly output is increased. ``What-if`` studies have been conducted to identify the cost of reducing constraints caused by increases in output requirement.

Rutherford, W.C.; Biggs, P.M.

1993-10-01T23:59:59.000Z

118

Noninvasive Characterization Of A Flowing Multiphase Fluid Using Ultrasonic Interferometry  

DOE Patents [OSTI]

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)

2005-05-10T23:59:59.000Z

119

Noninvasive characterization of a flowing multiphase fluid using ultrasonic interferometry  

DOE Patents [OSTI]

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.

2003-11-11T23:59:59.000Z

120

Noninvasive characterization of a flowing multiphase fluid using ultrasonic interferometry  

DOE Patents [OSTI]

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)

2007-06-12T23:59:59.000Z

Note: This page contains sample records for the topic "fluid flow simulation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Device and method for measuring multi-phase fluid flow in a conduit using an elbow flow meter  

DOE Patents [OSTI]

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)

1997-01-01T23:59:59.000Z

122

Device and method for measuring multi-phase fluid flow in a conduit using an elbow flow meter  

DOE Patents [OSTI]

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.

1997-06-24T23:59:59.000Z

123

Particle-fluid-structure interaction for debris flow impact on flexible barriers  

E-Print Network [OSTI]

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

2014-09-29T23:59:59.000Z

124

Preserving the Volume of Fluid Using Multi-phase Flow Approach Roman Durikovic  

E-Print Network [OSTI]

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

125

FLUID FLOW MODELING OF RESIN TRANSFER MOLDING FOR COMPOSITE MATERIAL WIND TURBINE BLADE STRUCTURES  

E-Print Network [OSTI]

FLUID FLOW MODELING OF RESIN TRANSFER MOLDING FOR COMPOSITE MATERIAL WIND TURBINE BLADE STRUCTURES.............................................................................................................7 Composite Materials...................................................................................................7 Material Properties

126

Implicit Large Eddy Simulation of Cavitation in Micro Channel Flows  

E-Print Network [OSTI]

We present a numerical method for Large Eddy Simulations (LES) of compressible two-phase flows. The method is validated for the flow in a micro channel with a step-like restriction. This setup is representative for typical cavitating multi-phase flows in fuel injectors and follows an experimental study of Iben et al., 2010. While a diesel-like test fuel was used in the experiment, we solve the compressible Navier-Stokes equations with a barotropic equation of state for water and vapor and a simple phase-change model based on equilibrium assumptions. Our LES resolve all wave dynamics in the compressible fluid and the turbulence production in shear layers.

Hickel, S; Schmidt, S J

2014-01-01T23:59:59.000Z

127

Heat transfer to a fluid flowing in an annulus  

E-Print Network [OSTI]

. 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

2012-06-07T23:59:59.000Z

128

Numerical Simulation of Bubble Formation in Co-Flowing Mercury  

SciTech Connect (OSTI)

In this work, we present computational fluid dynamics (CFD) simulations of helium bubble formation and detachment at a submerged needle in stagnant and co-flowing mercury. Since mercury is opaque, visualization of internal gas bubbles was done with proton radiography (pRad) at the Los Alamos Neutron Science Center (LANSCE2). The acoustic waves emitted at the time of detachment and during subsequent oscillations of the bubble were recorded with a microphone. The Volume of Fluid (VOF) model was used to simulate the unsteady two-phase flow of gas injection in mercury. The VOF model is validated by comparing detailed bubble sizes and shapes at various stages of the bubble growth and detachment, with the experimental measurements at different gas flow rates and mercury velocities. The experimental and computational results show a two-stage bubble formation. The first stage involves growing bubble around the needle, and the second follows as the buoyancy overcomes wall adhesion. The comparison of predicted and measured bubble sizes and shapes at various stages of the bubble growth and detachment is in good agreement.

Abdou, Ashraf A [ORNL; Wendel, Mark W [ORNL; Felde, David K [ORNL; Riemer, Bernie [ORNL

2008-01-01T23:59:59.000Z

129

Reducing or stopping the uncontrolled flow of fluid such as oil from a well  

DOE Patents [OSTI]

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

2014-02-18T23:59:59.000Z

130

High-Fidelity Simulation of Complex Suspension Flow for Practical...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

to develop a fundamental framework to understand important physical mechanisms that control the flow of such complex fluid systems. Results from this study will advance the...

131

Nested Cartesian grid method in incompressible viscous fluid flow Yih-Ferng Peng a,*, Rajat Mittal b  

E-Print Network [OSTI]

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

132

Flowing Liquid Crystal Simulating the Schwarzschild Metric  

E-Print Network [OSTI]

We show how to simulate the equatorial section of the Schwarzschild metric through a flowing liquid crystal in its nematic phase. Inside a liquid crystal in the nematic phase, a traveling light ray feels an effective metric, whose properties are linked to perpendicular and parallel refractive indexes, $n_o$ e $n_e$ respectively, of the rod-like molecule of the liquid crystal. As these indexes depend on the scalar order parameter of the liquid crystal, the Beris-Edwards hydrodynamic theory is used to connect the order parameter with the velocity of a liquid crystal flow at each point. This way we calculate a radial velocity profile that simulates the equatorial section of the Schwarzschild metric, in the region outside of Schwarzschild's radius, in the nematic phase of the liquid crystal. In our model, the higher flow velocity can be of the order of some meters per second.

Erms R. Pereira; Fernando Moraes

2010-11-21T23:59:59.000Z

133

Water and Mercury Pipe Flow Simulation in FLUENTSimulation in FLUENT  

E-Print Network [OSTI]

Water and Mercury Pipe Flow Simulation in FLUENTSimulation in FLUENT Yan Zhan, Foluso Ladeinde Stony Brook University thSep.21th , 2010 #12;OutlineOutline · Straight Pipe flowStraight Pipe flow · Curved pipe flow #12;OutlineOutline · Straight Pipe flowStraight Pipe flow · Curved pipe flow #12

McDonald, Kirk

134

Influence of formation clays on the flow of aqueous fluids  

SciTech Connect (OSTI)

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.

1981-01-01T23:59:59.000Z

135

Mesoscale Simulations of Particulate Flows with Parallel Distributed Lagrange Multiplier Technique  

SciTech Connect (OSTI)

Fluid particulate flows are common phenomena in nature and industry. Modeling of such flows at micro and macro levels as well establishing relationships between these approaches are needed to understand properties of the particulate matter. We propose a computational technique based on the direct numerical simulation of the particulate flows. The numerical method is based on the distributed Lagrange multiplier technique following the ideas of Glowinski et al. (1999). Each particle is explicitly resolved on an Eulerian grid as a separate domain, using solid volume fractions. The fluid equations are solved through the entire computational domain, however, Lagrange multiplier constrains are applied inside the particle domain such that the fluid within any volume associated with a solid particle moves as an incompressible rigid body. Mutual forces for the fluid-particle interactions are internal to the system. Particles interact with the fluid via fluid dynamic equations, resulting in implicit fluid-rigid-body coupling relations that produce realistic fluid flow around the particles (i.e., no-slip boundary conditions). The particle-particle interactions are implemented using explicit force-displacement interactions for frictional inelastic particles similar to the DEM method of Cundall et al. (1979) with some modifications using a volume of an overlapping region as an input to the contact forces. The method is flexible enough to handle arbitrary particle shapes and size distributions. A parallel implementation of the method is based on the SAMRAI (Structured Adaptive Mesh Refinement Application Infrastructure) library, which allows handling of large amounts of rigid particles and enables local grid refinement. Accuracy and convergence of the presented method has been tested against known solutions for a falling sphere as well as by examining fluid flows through stationary particle beds (periodic and cubic packing). To evaluate code performance and validate particle contact physics algorithm, we performed simulations of a representative experiment conducted at the University of California at Berkley for pebble flow through a narrow opening.

Kanarska, Y

2010-03-24T23:59:59.000Z

136

Monte Carlo Simulations of the two-dimensional dipolar fluid  

E-Print Network [OSTI]

We study a two-dimensional fluid of dipolar hard disks by Monte Carlo simulations in a square with periodic boundary conditions and on the surface of a sphere. The theory of the dielectric constant and the asymptotic behaviour of the equilibrium pair correlation function in the fluid phase is derived for both geometries. After having established the equivalence of the two methods we study the stability of the liquid phase in the canonical ensemble. We give evidence of a phase made of living polymers at low temperatures and provide a tentative phase diagram.

Caillol, Jean-Michel

2015-01-01T23:59:59.000Z

137

Nonlinear dynamics of magnetohydrodynamic flows of heavy fluid over an arbitrary surface  

E-Print Network [OSTI]

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

138

Abrupt contraction flow of magnetorheological fluids , M.T. Lpez-Lpez1,2  

E-Print Network [OSTI]

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

Boyer, Edmond

139

Simulation of Flow and Transport at the Micro (Pore) Scale  

SciTech Connect (OSTI)

An important problem in porous media involves the ability of micron and submicron-sized biological particles such as viruses or bacteria to move in groundwater systems through geologic media characterized by rock or mixed gravel, clay and sand materials. Current simulation capabilities require properly upscaled (continuum) models of colloidal filtration and adsorption to augment existing theories of fluid flow and chemical transport. Practical models typically address flow and transport behavior in aquifers over distances of 1 to 10 km where, for example, fluid momentum balance is governed by the simple Darcy's Law as a function of a pressure gradient, elevation gradient and a medium-dependent permeability parameter. In addition to fluid advection, there are multiple transport processes occurring in these systems including diffusion, dispersion and chemical interactions with solids or other aqueous chemical species. Particle transport is typically modeled in the same way as dissolved species, except that additional loss terms are incorporated to model particle filtration (physical interception), adsorption (chemical interception) and inactivation. Proper resolution of these processes at the porous medium continuum scale constitutes an important closure problem in subsurface science. We present a new simulation capability based on enabling technologies developed for microfluidics applications to model transport of colloidal-sized particles at the microscale, with relevance to the pore scale in geophysical subsurface systems. Particulate is represented by a bead-rod polymer model and is fully-coupled to a Newtonian solvent described by Navier-Stokes. Finite differences are used to discretize the interior of the domain; a Cartesian grid embedded boundary/volume-of-fluid method is used near boundaries and interfaces. This approach to complex geometry is amenable to direct simulation on grids obtained from surface extractions of tomographic image data. Short-range interactions are included in the particle model. This capability has been previously demonstrated on polymer flow in spatially-resolved packed bed (3D) and post array (2D) systems. We also discuss the advantages of this approach for the development of high-resolution adaptive algorithms for multiscale continuum-particle and mesoscale coarse-grained molecular dynamics models.

Trebotich, D; Miller, G H

2007-04-05T23:59:59.000Z

140

A Finite-Difference Numerical Method for Onsager's Pancake Approximation for Fluid Flow in a Gas Centrifuge  

SciTech Connect (OSTI)

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

2007-11-12T23:59:59.000Z

Note: This page contains sample records for the topic "fluid flow simulation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Hydrostatic bearings for a turbine fluid flow metering device  

DOE Patents [OSTI]

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.

1982-05-04T23:59:59.000Z

142

Hydrostatic bearings for a turbine fluid flow metering device  

DOE Patents [OSTI]

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)

1982-01-01T23:59:59.000Z

143

Microscale Fluid Flow Induced by Thermoviscous Expansion Along a Traveling Wave Franz M. Weinert,1  

E-Print Network [OSTI]

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

144

J. Non-Newtonian Fluid Mech. 136 (2006) 157166 A LagrangianEulerian approach for the numerical simulation of  

E-Print Network [OSTI]

CB3 0WA, UK b University of Cambridge, BP Institute & Engineering Department, Madingley Road, Cambridge CB3 0EZ, UK Received 17 January 2006; received in revised form 11 April 2006; accepted 11 April of view. Rasmussen and Hassager [1,2] simulate creeping flows of viscoelastic fluids described

Hinch, John

145

The Properties of Confined Water and Fluid Flow at the Nanoscale  

SciTech Connect (OSTI)

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

2009-03-09T23:59:59.000Z

146

Prolonged effect of fluid flow stress on the proliferative activity of mesothelial cells after abrupt discontinuation of fluid streaming  

SciTech Connect (OSTI)

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: aokis@cc.saga-u.ac.jp [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)

2011-12-16T23:59:59.000Z

147

Thermal Storage and Advanced Heat Transfer Fluids (Fact Sheet)  

SciTech Connect (OSTI)

Fact sheet describing NREL CSP Program capabilities in the area of thermal storage and advanced heat transfer fluids: measuring thermophysical properties, measuring fluid flow and heat transfer, and simulating flow of thermal energy and fluid.

Not Available

2010-08-01T23:59:59.000Z

148

Hydrostatic bearings for a turbine fluid flow metering device  

DOE Patents [OSTI]

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.

Fincke, J.R.

1980-05-02T23:59:59.000Z

149

Fluid breakup during simultaneous two-phase flow through a three-dimensional porous medium  

E-Print Network [OSTI]

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

2014-06-26T23:59:59.000Z

150

Wave-induced fluid flow in random porous media: Attenuation and ...  

E-Print Network [OSTI]

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-.

2005-04-20T23:59:59.000Z

151

Stress and Fluid-Flow Interaction for the Coso Geothermal Field...  

Open Energy Info (EERE)

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...

152

Adaptive LES Methodology for Turbulent Flow Simulations  

SciTech Connect (OSTI)

Although turbulent flows are common in the world around us, a solution to the fundamental equations that govern turbulence still eludes the scientific community. Turbulence has often been called one of the last unsolved problem in classical physics, yet it is clear that the need to accurately predict the effect of turbulent flows impacts virtually every field of science and engineering. As an example, a critical step in making modern computational tools useful in designing aircraft is to be able to accurately predict the lift, drag, and other aerodynamic characteristics in numerical simulations in a reasonable amount of time. Simulations that take months to years to complete are much less useful to the design cycle. Much work has been done toward this goal (Lee-Rausch et al. 2003, Jameson 2003) and as cost effective accurate tools for simulating turbulent flows evolve, we will all benefit from new scientific and engineering breakthroughs. The problem of simulating high Reynolds number (Re) turbulent flows of engineering and scientific interest would have been solved with the advent of Direct Numerical Simulation (DNS) techniques if unlimited computing power, memory, and time could be applied to each particular problem. Yet, given the current and near future computational resources that exist and a reasonable limit on the amount of time an engineer or scientist can wait for a result, the DNS technique will not be useful for more than 'unit' problems for the foreseeable future (Moin & Kim 1997, Jimenez & Moin 1991). The high computational cost for the DNS of three dimensional turbulent flows results from the fact that they have eddies of significant energy in a range of scales from the characteristic length scale of the flow all the way down to the Kolmogorov length scale. The actual cost of doing a three dimensional DNS scales as Re{sup 9/4} due to the large disparity in scales that need to be fully resolved. State-of-the-art DNS calculations of isotropic turbulence have recently been completed at the Japanese Earth Simulator (Yokokawa et al. 2002, Kaneda et al. 2003) using a resolution of 40963 (approximately 10{sup 11}) grid points with a Taylor-scale Reynolds number of 1217 (Re {approx} 10{sup 6}). Impressive as these calculations are, performed on one of the world's fastest super computers, more brute computational power would be needed to simulate the flow over the fuselage of a commercial aircraft at cruising speed. Such a calculation would require on the order of 10{sup 16} grid points and would have a Reynolds number in the range of 108. Such a calculation would take several thousand years to simulate one minute of flight time on today's fastest super computers (Moin & Kim 1997). Even using state-of-the-art zonal approaches, which allow DNS calculations that resolve the necessary range of scales within predefined 'zones' in the flow domain, this calculation would take far too long for the result to be of engineering interest when it is finally obtained. Since computing power, memory, and time are all scarce resources, the problem of simulating turbulent flows has become one of how to abstract or simplify the complexity of the physics represented in the full Navier-Stokes (NS) equations in such a way that the 'important' physics of the problem is captured at a lower cost. To do this, a portion of the modes of the turbulent flow field needs to be approximated by a low order model that is cheaper than the full NS calculation. This model can then be used along with a numerical simulation of the 'important' modes of the problem that cannot be well represented by the model. The decision of what part of the physics to model and what kind of model to use has to be based on what physical properties are considered 'important' for the problem. It should be noted that 'nothing is free', so any use of a low order model will by definition lose some information about the original flow.

Oleg V. Vasilyev

2008-06-12T23:59:59.000Z

153

System and method for bidirectional flow and controlling fluid flow in a conduit  

DOE Patents [OSTI]

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)

1999-01-01T23:59:59.000Z

154

System and method for bidirectional flow and controlling fluid flow in a conduit  

DOE Patents [OSTI]

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.

1999-03-23T23:59:59.000Z

155

CFD simulation of neutral ABL flows Xiaodong Zhang  

E-Print Network [OSTI]

Title: CFD simulation of neutral ABL flows Division: Aero-elastic Design ­ Wind Energy Division Risø flow field over different terrains employing Fluent 6.3 software. How accurate the simulation could.5 Comparison and conclusion 22 3.6 Closure 24 4 CFD Simulation of the Askervein Hill 24 4.1 Simulation

156

Closures for Course-Grid Simulation of Fluidized Gas-Particle Flows  

SciTech Connect (OSTI)

Gas-particle flows in fluidized beds and riser reactors are inherently unstable, and they manifest fluctuations over a wide range of length and time scales. Two-fluid models for such flows reveal unstable modes whose length scale is as small as ten particle diameters. Yet, because of limited computational resources, gas-particle flows in large fluidized beds are invariably simulated by solving discretized versions of the two-fluid model equations over a coarse spatial grid. Such coarse-grid simulations do not resolve the small-scale spatial structures which are known to affect the macroscale flow structures both qualitatively and quantitatively. Thus there is a need to develop filtered two-fluid models which are suitable for coarse-grid simulations and capturing the effect of the small-scale structures through closures in terms of the filtered variables. The overall objective of the project is to develop validated closures for filtered two-fluid models for gas-particle flows, with the transport gasifier as a primary, motivating example. In this project, highly resolved three-dimensional simulations of a kinetic theory based two-fluid model for gas-particle flows have been performed and the statistical information on structures in the 100-1000 particle diameters length scale has been extracted. Based on these results, closures for filtered two-fluid models have been constructed. The filtered model equations and closures have been validated against experimental data and the results obtained in highly resolved simulations of gas-particle flows. The proposed project enables more accurate simulations of not only the transport gasifier, but also many other non-reacting and reacting gas-particle flows in a variety of chemical reactors. The results of this study are in the form of closures which can readily be incorporated into existing multi-phase flow codes such as MFIX (www.mfix.org). Therefore, the benefits of this study can be realized quickly. The training provided by this project has prepared a PhD student to enter research and development careers in DOE laboratories or chemicals/energy-related industries.

Sankaran Sundaresan

2010-02-14T23:59:59.000Z

157

Nanoscale Pore Imaging and Pore Scale Fluid Flow Modeling in Chalk  

SciTech Connect (OSTI)

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

2004-08-19T23:59:59.000Z

158

DOE Fundamentals Handbook: Thermodynamics, Heat Transfer, and Fluid Flow, Volume 2  

SciTech Connect (OSTI)

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

1992-06-01T23:59:59.000Z

159

DOE Fundamentals Handbook: Thermodynamics, Heat Transfer, and Fluid Flow, Volume 1  

SciTech Connect (OSTI)

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

1992-06-01T23:59:59.000Z

160

DOE Fundamentals Handbook: Thermodynamics, Heat Transfer, and Fluid Flow, Volume 3  

SciTech Connect (OSTI)

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

1992-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "fluid flow simulation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Relation Between Flow Enhancement Factor and Structure for Core-Softened Fluids Inside Nanotubes  

E-Print Network [OSTI]

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.

162

Numerical modeling of heat transfer and fluid flow in rotor-stator cavities with throughflow  

E-Print Network [OSTI]

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

163

Global weak solutions to magnetic fluid flows with nonlinear Maxwell-Cattaneo heat transfer law  

E-Print Network [OSTI]

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

Boyer, Edmond

164

Using Euler-Lagrange Variational Principle to Obtain Flow Relations for Generalized Newtonian Fluids  

E-Print Network [OSTI]

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

2013-01-13T23:59:59.000Z

165

NUMERICAL STUDY OF FLUID FLOW AND HEAT TRANSFER OVER A SERIES OF IN-LINE NONCIRCULAR  

E-Print Network [OSTI]

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.

166

The effects of topology upon fluid-flow and heat-transfer within cellular copper structures  

E-Print Network [OSTI]

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

167

Pulsatile flow of a chemically-reacting non-linear fluid  

E-Print Network [OSTI]

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

2007-09-17T23:59:59.000Z

168

Development of one-dimensional computational fluid dynamics code 'GFLOW' for groundwater flow and contaminant transport analysis  

SciTech Connect (OSTI)

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)

2012-07-01T23:59:59.000Z

169

Subcritical finite-amplitude solutions in plane Couette flow of visco-elastic fluids  

E-Print Network [OSTI]

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

2004-11-10T23:59:59.000Z

170

Production of Natural Gas and Fluid Flow in Tight Sand Reservoirs  

SciTech Connect (OSTI)

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

2005-06-30T23:59:59.000Z

171

Magnetic fluid flow phenomena in DC and rotating magnetic fields  

E-Print Network [OSTI]

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-

2004-01-01T23:59:59.000Z

172

Time-lapse seismic monitoring of subsurface fluid flow  

E-Print Network [OSTI]

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.

2004-09-30T23:59:59.000Z

173

Computational fluid dynamics modeling of two-phase flow in a BWR fuel assembly. Final CRADA Report.  

SciTech Connect (OSTI)

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

2009-10-13T23:59:59.000Z

174

High Fidelity Simulation of Complex Suspension Flow for Practical...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

A visualization of the flow of concrete, a complex suspension A visualization of the flow of concrete, a complex suspension. In this snapshot of the simulation, the stress on each...

175

An overview of instability and fingering during immiscible fluid flow in porous and fractured media  

SciTech Connect (OSTI)

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

1995-04-01T23:59:59.000Z

176

Statistical Error in Particle Simulations of Low Mach Number Flows  

E-Print Network [OSTI]

We present predictions for the statistical error due to finite sampling in the presence of thermal fluctuations in molecular simulation algorithms. Expressions for the fluid velocity, density and temperature are derived ...

Hadjiconstantinou, Nicolas G.

177

Dynamic dielectric response of electrorheological fluids in drag and pressure flow  

E-Print Network [OSTI]

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. Horvth; I. Szalai

2014-12-30T23:59:59.000Z

178

Sediment Transport in Shallow Subcritical Flow Disturbed by Simulated Rainfall  

E-Print Network [OSTI]

TR-14 1968 Sediment Transport in Shallow Subcritical Flow Disturbed by Simulated Rainfall J.L. Machemehl Texas Water Resources Institute Texas A&M University ...

Machemehl, J. L.

179

GPU accelerated flow solver for direct numerical simulation of turbulent flows  

SciTech Connect (OSTI)

Graphical processing units (GPUs), characterized by significant computing performance, are nowadays very appealing for the solution of computationally demanding tasks in a wide variety of scientific applications. However, to run on GPUs, existing codes need to be ported and optimized, a procedure which is not yet standardized and may require non trivial efforts, even to high-performance computing specialists. In the present paper we accurately describe the porting to CUDA (Compute Unified Device Architecture) of a finite-difference compressible NavierStokes solver, suitable for direct numerical simulation (DNS) of turbulent flows. Porting and validation processes are illustrated in detail, with emphasis on computational strategies and techniques that can be applied to overcome typical bottlenecks arising from the porting of common computational fluid dynamics solvers. We demonstrate that a careful optimization work is crucial to get the highest performance from GPU accelerators. The results show that the overall speedup of one NVIDIA Tesla S2070 GPU is approximately 22 compared with one AMD Opteron 2352 Barcelona chip and 11 compared with one Intel Xeon X5650 Westmere core. The potential of GPU devices in the simulation of unsteady three-dimensional turbulent flows is proved by performing a DNS of a spatially evolving compressible mixing layer.

Salvadore, Francesco [CASPUR via dei Tizii 6/b, 00185 Rome (Italy)] [CASPUR via dei Tizii 6/b, 00185 Rome (Italy); Bernardini, Matteo, E-mail: matteo.bernardini@uniroma1.it [Department of Mechanical and Aerospace Engineering, University of Rome La Sapienza via Eudossiana 18, 00184 Rome (Italy)] [Department of Mechanical and Aerospace Engineering, University of Rome La Sapienza via Eudossiana 18, 00184 Rome (Italy); Botti, Michela [CASPUR via dei Tizii 6/b, 00185 Rome (Italy)] [CASPUR via dei Tizii 6/b, 00185 Rome (Italy)

2013-02-15T23:59:59.000Z

180

2.13 HEAT TRANSFER & FLUID FLOW IN MICROCHANNELS 2.13.7-1 Molecular dynamics methods in  

E-Print Network [OSTI]

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

Note: This page contains sample records for the topic "fluid flow simulation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Numerical Simulation of Flow Field Inside a Squeeze Film Damper and the Study of the Effect of Cavitation on the Pressure Distribution  

E-Print Network [OSTI]

of SFDs can be expensive and time consuming. The current work simulates the flow field inside the dynamically deforming annular gap of a SFD using the commercial computational fluid dynamics (CFD) code Fluent and compares the results to the experimental...

Khandare, Milind Nandkumar

2012-02-14T23:59:59.000Z

182

Method and apparatus for measuring the mass flow rate of a fluid  

DOE Patents [OSTI]

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)

2002-01-01T23:59:59.000Z

183

Direct numerical simulation of turbulent reacting flows  

SciTech Connect (OSTI)

The development of turbulent combustion models that reflect some of the most important characteristics of turbulent reacting flows requires knowledge about the behavior of key quantities in well defined combustion regimes. In turbulent flames, the coupling between the turbulence and the chemistry is so strong in certain regimes that is is very difficult to isolate the role played by one individual phenomenon. Direct numerical simulation (DNS) is an extremely useful tool to study in detail the turbulence-chemistry interactions in certain well defined regimes. Globally, non-premixed flames are controlled by two limiting cases: the fast chemistry limit, where the turbulent fluctuations. In between these two limits, finite-rate chemical effects are important and the turbulence interacts strongly with the chemical processes. This regime is important because industrial burners operate in regimes in which, locally the flame undergoes extinction, or is at least in some nonequilibrium condition. Furthermore, these nonequilibrium conditions strongly influence the production of pollutants. To quantify the finite-rate chemistry effect, direct numerical simulations are performed to study the interaction between an initially laminar non-premixed flame and a three-dimensional field of homogeneous isotropic decaying turbulence. Emphasis is placed on the dynamics of extinction and on transient effects on the fine scale mixing process. Differential molecular diffusion among species is also examined with this approach, both for nonreacting and reacting situations. To address the problem of large-scale mixing and to examine the effects of mean shear, efforts are underway to perform large eddy simulations of round three-dimensional jets.

Chen, J.H. [Sandia National Laboratories, Livermore, CA (United States)

1993-12-01T23:59:59.000Z

184

MOLECULAR SIMULATION OF PHASE EQUILIBRIA FOR COMPLEX FLUIDS  

SciTech Connect (OSTI)

The general area of this project was the development and application of novel molecular simulation methods for prediction of thermodynamic and structural properties of complex polymeric, surfactant and ionic fluids. Over this project period, we have made considerable progress in developing novel algorithms to meet the computational challenges presented by the strong or long-range interactions in these systems and have generated data for well-defined mod-els that can be used to test theories and compare to experimental data. Overall, 42 archival papers and many invited and contributed presentations and lectures have been based on work supported by this project. 6 PhD, 1 M.S. and 2 postdoctoral students have been associated with this work, as listed in the body of the report.

Athanassios Z. Panagiotopoulos

2009-09-09T23:59:59.000Z

185

Dispersion of swimming algae in laminar and turbulent channel flows: theory and simulations  

E-Print Network [OSTI]

Algal swimming is often biased by environmental cues, e.g. gravitational and viscous torques drive cells towards downwelling fluid (gyrotaxis). In view of biotechnological applications, it is important to understand how such biased swimming affects cell dispersion in a flow. Here, we study the dispersion of gyrotactic swimming algae in laminar and turbulent channel flows. By direct numerical simulation (DNS) of cell motion within upwelling and downwelling channel flows, we evaluate time-dependent measures of dispersion for increasing values of the flow Peclet (Reynolds) numbers, Pe (Re). Furthermore, we derive an analytical `swimming Taylor-Aris dispersion' theory, using flow-dependent transport parameters given by existing microscopic models. In the laminar regime, DNS results and analytical predictions compare very well, providing the first confirmation that cells' response to flow is best described by the generalized-Taylor-dispersion microscopic model. We predict that cells drift along a channel faster th...

Croze, O A; Ahmed, M; Bees, M A; Brandt, L

2012-01-01T23:59:59.000Z

186

Enhanced Geothermal Systems Research and Development: Models of Subsurface Chemical Processes Affecting Fluid Flow  

SciTech Connect (OSTI)

Successful exploitation of the vast amount of heat stored beneath the earths surface in hydrothermal and fluid-limited, low permeability geothermal resources would greatly expand the Nations 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 < 350C) 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 < 350C). Aluminum is the third most abundant element in the earths crust; and, as a constituent of aluminosilicate minerals, it is found in two thirds of the minerals in the earths 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 300C. 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.

2008-05-29T23:59:59.000Z

187

Modeling Fluid Flow in Natural Systems, Model Validation and...  

Broader source: Energy.gov (indexed) [DOE]

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...

188

REYNOLDS STRESS MODEL IMPLEMENTATION FOR HYPERSONIC FLOW SIMULATIONS  

E-Print Network [OSTI]

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

189

MULTITARGET ERROR ESTIMATION AND ADAPTIVITY IN AERODYNAMIC FLOW SIMULATIONS  

E-Print Network [OSTI]

MULTI­TARGET ERROR ESTIMATION AND ADAPTIVITY IN AERODYNAMIC FLOW SIMULATIONS RALF HARTMANN # Abstract. Important quantities in aerodynamic flow simulations are the aerodynamic force coe subject classifications. 65N12,65N15,65N30 1. Introduction. In aerodynamic computations like compressible

Hartmann, Ralf

190

MULTITARGET ERROR ESTIMATION AND ADAPTIVITY IN AERODYNAMIC FLOW SIMULATIONS  

E-Print Network [OSTI]

MULTITARGET ERROR ESTIMATION AND ADAPTIVITY IN AERODYNAMIC FLOW SIMULATIONS RALF HARTMANN Abstract. Important quantities in aerodynamic flow simulations are the aerodynamic force coefficients including Navier-Stokes equations AMS subject classifications. 65N12,65N15,65N30 1. Introduction. In aerodynamic

Hartmann, Ralf

191

6. Fluid mechanics: fluid statics; fluid dynamics  

E-Print Network [OSTI]

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

192

Fluid Flow and Infiltration in Structured Fibrous Porous Media  

SciTech Connect (OSTI)

Present the results of an extensive computational investigation of flow through structured fibrous media.

Papathanasiou, Thanasis D.

2006-08-09T23:59:59.000Z

193

The stability of viscoelastic fluids in complex flows : the role of shear and extensional rheology  

E-Print Network [OSTI]

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-

2001-01-01T23:59:59.000Z

194

Analysis of multiphase fluid flows via high speed and synthetic aperture three dimensional imaging  

E-Print Network [OSTI]

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

2012-01-01T23:59:59.000Z

195

IN SITU STRESS, FRACTURE AND FLUID FLOW ANALYSIS-EAST FLANK OF...  

Open Energy Info (EERE)

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,...

196

IN SITU STRESS, FRACTURE, AND FLUID FLOW ANALYSIS IN WELL 38C...  

Open Energy Info (EERE)

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...

197

In situ stress, fracture, and fluid flow analysis in Well 38C...  

Open Energy Info (EERE)

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...

198

Permeability of illite-bearing shale: 2. Influence of fluid chemistry on flow and functionally  

E-Print Network [OSTI]

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

199

Tritium flow through a non-symmetrical source. Simulation of gas flow through an injection hole  

E-Print Network [OSTI]

Tritium flow through a non-symmetrical source. Simulation of gas flow through an injection hole of source in injection rarefaction parameter µ0 viscosity of tritium at T0 Pa s 2 #12;Ll = 5074.5 Lr = 5007

Sharipov, Felix

200

An implicit centered finite-difference simulation for free surface flows in a rocking tank  

E-Print Network [OSTI]

include the liquid movement in closed containers such as tank trucks on highways and railroads, liquid fuel tanks in space vehicles' and contained liquid cargo in oceangoing vessels. Interest in this particular fluid phenomenon has grown consider...AN IMPLICIT CENTERED FINITE-DIFFERENCE SIMULATION FOR FREE SURFACE FLOWS IN A ROCKING TANK A Thesis by WILLIAM EDWARD JOBST Submitted to the Graduate College of Texas A8M University in partial fulfillment of the requirement for the degree...

Jobst, William Edward

1982-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "fluid flow simulation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Computational Fluid Dynamics Modeling of a Lithium/Thionyl Chloride Battery with Electrolyte Flow  

E-Print Network [OSTI]

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

202

American Institute of Aeronautics and Astronautics Three-dimensional Plasma and Fluid Flow Structures inside a  

E-Print Network [OSTI]

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

203

Cartesian Cut Cell Two-Fluid Solver for Hydraulic Flow Problems  

E-Print Network [OSTI]

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

204

FLOW OF A FLUID THROUGH A POROUS SOLID DUE TO HIGH PRESSURE GRADIENTS  

E-Print Network [OSTI]

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

205

High Resolution Wave Propagation Schemes for Two-Fluid Plasma Simulations  

E-Print Network [OSTI]

High Resolution Wave Propagation Schemes for Two-Fluid Plasma Simulations Ammar H. Hakim Information and Learning, 300 North Zeeb Road, Ann Arbor, MI 48106-1346, 1-800-521-0600, to whom the author Abstract High Resolution Wave Propagation Schemes for Two-Fluid Plasma Simulations Ammar H. Hakim Chair

Shumlak, Uri

206

Large-eddy simulation of multiphase flows in complex combustors  

E-Print Network [OSTI]

Large-eddy simulation of multiphase flows in complex combustors S. V. Apte1 , K. Mahesh2 , F. Ham1 to accurately predict reacting multi-phase flows in practical combustors involving complex physical phenomena-turbine combustor geometries to evaluate the predictions made for multiphase, turbulent flow. 1 Introduction

Mahesh, Krishnan

207

Bluff Body Flow Simulation Using a Vortex Element Method  

SciTech Connect (OSTI)

Heavy ground vehicles, especially those involved in long-haul freight transportation, consume a significant part of our nation's energy supply. it is therefore of utmost importance to improve their efficiency, both to reduce emissions and to decrease reliance on imported oil. At highway speeds, more than half of the power consumed by a typical semi truck goes into overcoming aerodynamic drag, a fraction which increases with speed and crosswind. Thanks to better tools and increased awareness, recent years have seen substantial aerodynamic improvements by the truck industry, such as tractor/trailer height matching, radiator area reduction, and swept fairings. However, there remains substantial room for improvement as understanding of turbulent fluid dynamics grows. The group's research effort focused on vortex particle methods, a novel approach for computational fluid dynamics (CFD). Where common CFD methods solve or model the Navier-Stokes equations on a grid which stretches from the truck surface outward, vortex particle methods solve the vorticity equation on a Lagrangian basis of smooth particles and do not require a grid. They worked to advance the state of the art in vortex particle methods, improving their ability to handle the complicated, high Reynolds number flow around heavy vehicles. Specific challenges that they have addressed include finding strategies to accurate capture vorticity generation and resultant forces at the truck wall, handling the aerodynamics of spinning bodies such as tires, application of the method to the GTS model, computation time reduction through improved integration methods, a closest point transform for particle method in complex geometrics, and work on large eddy simulation (LES) turbulence modeling.

Anthony Leonard; Phillippe Chatelain; Michael Rebel

2004-09-30T23:59:59.000Z

208

Monitoring and Modeling Fluid Flow in a Developing EGS Reservoir  

Broader source: Energy.gov [DOE]

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.

209

Multiphase flow and control of fluid path in microsystems  

E-Print Network [OSTI]

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

2005-01-01T23:59:59.000Z

210

TOUGH2: A general-purpose numerical simulator for multiphase nonisothermal flows  

SciTech Connect (OSTI)

Numerical simulators for multiphase fluid and heat flows in permeable media have been under development at Lawrence Berkeley Laboratory for more than 10 yr. Real geofluids contain noncondensible gases and dissolved solids in addition to water, and the desire to model such `compositional` systems led to the development of a flexible multicomponent, multiphase simulation architecture known as MULKOM. The design of MULKOM was based on the recognition that the mass-and energy-balance equations for multiphase fluid and heat flows in multicomponent systems have the same mathematical form, regardless of the number and nature of fluid components and phases present. Application of MULKOM to different fluid mixtures, such as water and air, or water, oil, and gas, is possible by means of appropriate `equation-of-state` (EOS) modules, which provide all thermophysical and transport parameters of the fluid mixture and the permeable medium as a function of a suitable set of primary thermodynamic variables. Investigations of thermal and hydrologic effects from emplacement of heat-generating nuclear wastes into partially water-saturated formations prompted the development and release of a specialized version of MULKOM for nonisothermal flow of water and air, named TOUGH. TOUGH is an acronym for `transport of unsaturated groundwater and heat` and is also an allusion to the tuff formations at Yucca Mountain, Nevada. The TOUGH2 code is intended to supersede TOUGH. It offers all the capabilities of TOUGH and includes a considerably more general subset of MULKOM modules with added capabilities. The paper briefly describes the simulation methodology and user features.

Pruess, K. [Lawrence Berkeley Lab., CA (United States)

1991-06-01T23:59:59.000Z

211

A correction function method to solve incompressible fluid flows to high accuracy with immersed geometries  

E-Print Network [OSTI]

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

2012-01-01T23:59:59.000Z

212

Flow and heat transfer of a third grade fluid past an exponentially stretching sheet with  

E-Print Network [OSTI]

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

Paris-Sud XI, Université de

213

SUBCRITICAL INSTABILITIES IN PLANE COUETTE FLOW OF VISCO-ELASTIC FLUIDS  

E-Print Network [OSTI]

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

214

Parameter estimation from flowing fluid temperature logging data in unsaturated fractured rock using multiphase inverse modeling  

SciTech Connect (OSTI)

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.

2009-01-15T23:59:59.000Z

215

Numerical simulation of the flow field and the lifting forces in the bristle tip region of a brush seal  

E-Print Network [OSTI]

The complicated fluid flow at the tip of a typical bristle within a brush seal is simulated. A numerical model is developed to compute the three-dimensional details in the bristle tip region. Experimental and numerical leakage data are correlated...

Phung, Anh Ngoc

1995-01-01T23:59:59.000Z

216

Role of viscoelasticity and non-linear rheology in flows of complex fluids at high deformation rates  

E-Print Network [OSTI]

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)

2013-01-01T23:59:59.000Z

217

Grid adaptation for functional outputs of compressible flow simulations  

E-Print Network [OSTI]

An error correction and grid adaptive method is presented for improving the accuracy of functional outputs of compressible flow simulations. The procedure is based on an adjoint formulation in which the estimated error in ...

Venditti, David Anthony, 1973-

2002-01-01T23:59:59.000Z

218

Dissolution rates of uranium compounds in simulated lung fluid  

SciTech Connect (OSTI)

Maximum dissolution rates of uranium into simulated lung fluid from a variety of materials were measured at 37/sup 0/in the where f/sub i/ is in order to estimate clearance rates from the deep lung. A batch procedure was utilized in which samples containing as little as 10 ..mu..g of natural uranium could be tested. The materials included: products of uranium mining, milling and refining operations, coal fly ash, an environmental sample from a site exposed to multiple uranium sources, and purified samples of (NH/sub 4/)/sub 2/U/sub 2/O/sub 7/ U/sub 3/O/sub 8/, UO/sub 2/, and UF/sub 4/. Dissolution of uranium from several materials indicated the presence of more than one type of uranium compound; but in all cases, the fraction F of uranium remaining undissolved at any time t could be represented by the sum of up to three terms in the series: F = ..sigma../sub i/f/sub i/ exp (-0.693t/UPSILON/sub i/), where f/sub i/ is the initial fraction of component i with dissolution half-time epsilon/sub i/. Values of epsilon/sub i/ varied from 0.01 day to several thousand days depending on the physical and chemical form of the uranium. Dissolution occurred predominantly by formation of the (UO/sub 2/(CO/sub 3/)/sub 3/)/sup 4 -/ ion; and as a result, tetravalent uranium compounds dissolved slowly. Dissolution rates of size-separated yellow-cake aerosols were found to be more closely correlated with specific surface area than with aerodynamic diameter.

Kalkwarf, D.R.

1981-01-01T23:59:59.000Z

219

Fluid dynamics of dilatant fluid  

E-Print Network [OSTI]

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

2011-12-20T23:59:59.000Z

220

Multiscale CFD simulations of entrained flow gasification  

E-Print Network [OSTI]

The design of entrained flow gasifiers and their operation has largely been an experience based enterprise. Most, if not all, industrial scale gasifiers were designed before it was practical to apply CFD models. Moreover, ...

Kumar, Mayank, Ph. D. Massachusetts Institute of Technology

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "fluid flow simulation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Simulation of Coupled Processes of Flow, Transport, and Storage of CO2 in Saline Aquifers  

SciTech Connect (OSTI)

This report is the final scientific one for the award DE- FE0000988 entitled Simulation of Coupled Processes of Flow, Transport, and Storage of CO2 in Saline Aquifers. The work has been divided into six tasks. In task, Development of a Three-Phase Non-Isothermal CO2 Flow Module, we developed a fluid property module for brine-CO2 mixtures designed to handle all possible phase combinations of aqueous phase, sub-critical liquid and gaseous CO2, supercritical CO2, and solid salt. The thermodynamic and thermophysical properties of brine-CO2 mixtures (density, viscosity, and specific enthalpy of fluid phases; partitioning of mass components among the different phases) use the same correlations as an earlier fluid property module that does not distinguish between gaseous and liquid CO2-rich phases. We verified the fluid property module using two leakage scenarios, one that involves CO2 migration up a blind fault and subsequent accumulation in a secondary parasitic reservoir at shallower depth, and another investigating leakage of CO2 from a deep storage reservoir along a vertical fault zone. In task, Development of a Rock Mechanical Module, we developed a massively parallel reservoir simulator for modeling THM processes in porous media brine aquifers. We derived, from the fundamental equations describing deformation of porous elastic media, a momentum conservation equation relating mean stress, pressure, and temperature, and incorporated it alongside the mass and energy conservation equations from the TOUGH2 formulation, the starting point for the simulator. In addition, rock properties, namely permeability and porosity, are functions of effective stress and other variables that are obtained from the literature. We verified the simulator formulation and numerical implementation using analytical solutions and example problems from the literature. For the former, we matched a one-dimensional consolidation problem and a two-dimensional simulation of the Mandel-Cryer effect. For the latter, we obtained a good match of temperature and gas saturation profiles, and surface uplift, after injection of hot fluid into a model of a caldera structure. In task, Incorporation of Geochemical Reactions of Selected Important Species, we developed a novel mathematical model of THMC processes in porous and fractured saline aquifers, simulating geo-chemical reactions associated with CO2 sequestration in saline aquifers. Two computational frameworks, sequentially coupled and fully coupled, were used to simulate the reactions and transport. We verified capabilities of the THMC model to treat complex THMC processes during CO2 sequestration by analytical solutions and we constructed reactive transport models to analyze the THMC process quantitatively. Three of these are 1D reactive transport under chemical equilibrium, a batch reaction model with equilibrium chemical reactions, and a THMC model with CO2 dissolution. In task Study of Instability in CO2 Dissolution-Diffusion-Convection Processes, We reviewed literature related to the study of density driven convective flows and on the instability of CO2 dissolution-diffusion-convection processes. We ran simulations that model the density-driven flow instability that would occur during CO2 sequestration. CO2 diffused through the top of the system and dissolved in the aqueous phase there, increasing its density. Density fingers formed along the top boundary, and coalesced into a few prominent ones, causing convective flow that forced the fluid to the system bottom. These simulations were in two and three dimensions. We ran additional simulations of convective mixing with density contrast caused by variable dissolved CO2 concentration in saline water, modeled after laboratory experiments in which supercritical CO2 was circulated in the headspace above a brine saturated packed sand in a pressure vessel. As CO2 dissolved into the upper part of the saturated sand, liquid phase density increases causing instability and setting off convective mixing. We obtained good agreement

Wu, Yu-Shu; Chen, Zizhong; Kazemi, Hossein; Yin, Xiaolong; Pruess, Karsten; Oldenburg, Curt; Winterfeld, Philip; Zhang, Ronglei

2014-09-30T23:59:59.000Z

222

NMRI methods for characterizing fluid flow in porous media  

E-Print Network [OSTI]

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

1997-01-01T23:59:59.000Z

223

Porosity, Permeability, And Fluid Flow In The Yellowstone Geothermal...  

Open Energy Info (EERE)

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...

224

A MEMS BODY FLUID FLOW SENSOR Ellis Meng1  

E-Print Network [OSTI]

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

225

Fluid-elastic Instability of Helical Tubes Subjected to Single-Phase External Flow and Two-Phase Internal Flow  

SciTech Connect (OSTI)

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)

2004-07-01T23:59:59.000Z

226

PHYSICS OF FLUIDS 24, 103306 (2012) Numerical simulation of turbulent sediment transport,  

E-Print Network [OSTI]

PHYSICS OF FLUIDS 24, 103306 (2012) Numerical simulation of turbulent sediment transport, from bed October 2012) Sediment transport is studied as a function of the grain to fluid density ratio using two), vertical velocities are so small that sediment transport occurs in a thin layer at the surface

Claudin, Philippe

227

Developing an integrated building design tool by coupling building energy simulation and computational fluid dynamics programs  

E-Print Network [OSTI]

Building energy simulation (ES) and computational fluid dynamics (CFD) can play important roles in building design by providing essential information to help design energy-efficient, thermally comfortable and healthy ...

Zhai, Zhiqiang, 1971-

2003-01-01T23:59:59.000Z

228

Parallel Simulation of Subsonic Fluid Dynamics on a Cluster of Workstations  

E-Print Network [OSTI]

An effective approach of simulating fluid dynamics on a cluster of non- dedicated workstations is presented. The approach uses local interaction algorithms, small communication capacity, and automatic migration of parallel ...

Skordos, Panayotis A.

1995-12-01T23:59:59.000Z

229

Nonequilibrium molecular dynamics simulations of confined fluids in contact with the bulk  

E-Print Network [OSTI]

Nonequilibrium molecular dynamics simulations of confined fluids in contact with the bulk Luzheng Zhang, Ramkumar Balasundaram,a) and Stevin H. Gehrke Department of Chemical Engineering, Kansas State University, Manhattan, Kansas 66506 Shaoyi Jiangb) Department of Chemical Engineering, University

Zhang, Luzheng

230

Investigation of two-fluid methods for Large Eddy Simulation of spray combustion in Gas Turbines  

E-Print Network [OSTI]

Investigation of two-fluid methods for Large Eddy Simulation of spray combustion in Gas Turbines the EL method well suited for gas turbine computations, but RANS with the EE approach may also be found

231

Start-up flow of a viscoelastic fluid in a pipe with fractional Maxwell's model  

E-Print Network [OSTI]

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

2010-06-27T23:59:59.000Z

232

Effect of Fluid Flow on Inclusion Coarsening in Low-Alloy Steel Welds  

SciTech Connect (OSTI)

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.

1998-02-28T23:59:59.000Z

233

Non-Steady wall-bounded flows of viscoelastic fluids under periodic forcing  

E-Print Network [OSTI]

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 Hernndez-Garca; Antonio Fernndez-Barbero; Oscar Sotolongo-Costa

2013-01-18T23:59:59.000Z

234

Heat transfer and fluid flow characteristics in various micro devices for the development of micro absorption heat pump systems.  

E-Print Network [OSTI]

??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

2007-01-01T23:59:59.000Z

235

One- and two-dimensional Stirling machine simulation using experimentally generated reversing flow turbuulence models  

SciTech Connect (OSTI)

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)

1990-08-01T23:59:59.000Z

236

Microscale fluid flow induced by thermoviscous expansion along a traveling wave  

E-Print Network [OSTI]

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

2008-04-02T23:59:59.000Z

237

Method and apparatus for simultaneous determination of fluid mass flow rate, mean velocity and density  

DOE Patents [OSTI]

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)

1984-01-01T23:59:59.000Z

238

FastStokes : a fast 3-D fluid simulation program for micro-electro-mechanical systems  

E-Print Network [OSTI]

We have developed boundary integral equation formulas and a corresponding fast 3-D Stokes flow simulation program named FastStokes to accurately simulate viscous drag forces on geometrically complicated MEMS (micro- electro- ...

Wang, Xin, 1972 Jan. 8-

2002-01-01T23:59:59.000Z

239

Update and assessment of geothermal economic models, geothermal fluid flow and heat distribution models, and geothermal data bases  

SciTech Connect (OSTI)

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.)

1985-05-01T23:59:59.000Z

240

Energy of eigen-modes in magnetohydrodynamic flows of ideal fluids  

E-Print Network [OSTI]

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

2007-12-11T23:59:59.000Z

Note: This page contains sample records for the topic "fluid flow simulation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Computational Methods for Analyzing Fluid Flow Dynamics from Digital Imagery  

SciTech Connect (OSTI)

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.

2012-03-30T23:59:59.000Z

242

A Preliminary Study to Assess Model Uncertainties in Fluid Flows  

E-Print Network [OSTI]

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

2011-08-08T23:59:59.000Z

243

Submarine landslide flows simulation through centrifuge modelling  

E-Print Network [OSTI]

) ........ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 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

2012-05-08T23:59:59.000Z

244

FLUID FLOW AND PARTICLE DEPOSITION SIMULATIONS IN THE HUMAN NOSE  

E-Print Network [OSTI]

. Melaaen Telemark University College (HiT-TF) and Telemark R&D Centre (Tel-Tek) Porsgrunn Norway Martin

Reimers, Martin

245

Numerical simulation of two-phase fluid flow  

E-Print Network [OSTI]

42c, 34010 Sgonico, Trieste, Italy. E-mail: jcarcione@inogs.it. 2 CONICET, Departamento de Geof?sica Aplicada, Fac. Ciencias Astronmicas y Geof?sicas,.

2013-01-30T23:59:59.000Z

246

Numerical Simulation of Compositional Fluid Flow in Porous Media  

E-Print Network [OSTI]

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

Ewing, Richard E.

247

Comparative Analysis of Natural Convection Flows Simulated by both the Conservation and Incompressible Forms of the Navier-Stokes Equations in a Differentially-Heated Square Cavity  

SciTech Connect (OSTI)

This report illustrates a comparative study to analyze the physical differences between numerical simulations obtained with both the conservation and incompressible forms of the Navier-Stokes equations for natural convection flows in simple geometries. The purpose of this study is to quantify how the incompressible flow assumption (which is based upon constant density advection, divergence-free flow, and the Boussinesq gravitational body force approximation) differs from the conservation form (which only assumes that the fluid is a continuum) when solving flows driven by gravity acting upon density variations resulting from local temperature gradients. Driving this study is the common use of the incompressible flow assumption in fluid flow simulations for nuclear power applications in natural convection flows subjected to a high heat flux (large temperature differences). A series of simulations were conducted on two-dimensional, differentially-heated rectangular geometries and modeled with both hydrodynamic formulations. From these simulations, the selected characterization parameters of maximum Nusselt number, average Nusselt number, and normalized pressure reduction were calculated. Comparisons of these parameters were made with available benchmark solutions for air with the ideal gas assumption at both low and high heat fluxes. Additionally, we generated body force, velocity, and divergence of velocity distributions to provide a basis for further analysis. The simulations and analysis were then extended to include helium at the Very High Temperature gas-cooled Reactor (VHTR) normal operating conditions. Our results show that the consequences of incorporating the incompressible flow assumption in high heat flux situations may lead to unrepresentative results. The results question the use of the incompressible flow assumption for simulating fluid flow in an operating nuclear reactor, where large temperature variations are present. The results show that the use of the incompressible flow assumption with the Boussinesq gravitational body force approximation should be restricted to flows where the density change of a fluid particle along a pathline is negligible.

Richard C. Martineau; Ray A. Berry; Aurlia Esteve; Kurt D. Hamman; Dana A. Knoll; Ryosuke Park; William Taitano

2009-01-01T23:59:59.000Z

248

Simulation of dust streaming in toroidal traps: Stationary flows  

SciTech Connect (OSTI)

Molecular-dynamic simulations were performed to study dust motion in a toroidal trap under the influence of the ion drag force driven by a Hall motion of the ions in E x B direction, gravity, inter-particle forces, and friction with the neutral gas. This article is focused on the inhomogeneous stationary streaming motion. Depending on the strength of friction, the spontaneous formation of a stationary shock or a spatial bifurcation into a fast flow and a slow vortex flow is observed. In the quiescent streaming region, the particle flow features a shell structure which undergoes a structural phase transition along the flow direction.

Reichstein, Torben; Piel, Alexander [IEAP, Christian-Albrechts-Universitaet, D-24098 Kiel (Germany)

2011-08-15T23:59:59.000Z

249

1. INTRODUCTION Fluid flows are often so complicated that laboratory  

E-Print Network [OSTI]

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

250

Analytical solutions for the flow of Carreau and Cross fluids in circular pipes and thin slits  

E-Print Network [OSTI]

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

2015-01-01T23:59:59.000Z

251

Theory and simulations of the scaling of magnetic reconnection with symmetric shear flow  

SciTech Connect (OSTI)

The scaling of magnetic reconnection in the presence of an oppositely directed sub-Alfvenic shear flow parallel to the reconnecting magnetic field is studied using analytical scaling arguments and two-dimensional two-fluid numerical simulations of collisionless (Hall) reconnection. Previous studies noted that the reconnection rate falls and the current sheet tilts with increasing flow speed, but no quantitative theory was presented. This study presents a physical model of the effect of shear flow on reconnection, resulting in expressions for the scaling of properties such as the reconnection rate, outflow speed, and thickness and length of the dissipation region, which are verified numerically. Differences between Hall and Sweet-Parker reconnection are pointed out. The tilting of the current sheet is explained physically and a quantitative prediction is presented and verified.

Cassak, P. A. [Department of Physics, West Virginia University, Morgantown, West Virginia 26506 (United States)

2011-07-15T23:59:59.000Z

252

Resistive MHD Simulations of Laminar Round Jets with Application to Magnetic Nozzle Flows  

E-Print Network [OSTI]

of simulating magnetic nozzle flows and other plasmas that cannot be easily replicated in ground facilities....

Araya, Daniel

2012-02-14T23:59:59.000Z

253

Two-Dimensional Computational Fluid Dynamics and Conduction Simulations of Heat Transfer in Horizontal Window Frames with Internal Cavities  

SciTech Connect (OSTI)

This paper assesses the accuracy of the simplified frame cavity conduction/convection and radiation models presented in ISO 15099 and used in software for rating and labeling window products. Temperatures and U-factors for typical horizontal window frames with internal cavities are compared; results from Computational Fluid Dynamics (CFD) simulations with detailed radiation modeling are used as a reference. Four different frames were studied. Two were made of polyvinyl chloride (PVC) and two of aluminum. For each frame, six different simulations were performed, two with a CFD code and four with a building-component thermal-simulation tool using the Finite Element Method (FEM). This FEM tool addresses convection using correlations from ISO 15099; it addressed radiation with either correlations from ISO 15099 or with a detailed, view-factor-based radiation model. Calculations were performed using the CFD code with and without fluid flow in the window frame cavities; the calculations without fluid flow were performed to verify that the CFD code and the building-component thermal-simulation tool produced consistent results. With the FEM-code, the practice of subdividing small frame cavities was examined, in some cases not subdividing, in some cases subdividing cavities with interconnections smaller than five millimeters (mm) (ISO 15099) and in some cases subdividing cavities with interconnections smaller than seven mm (a breakpoint that has been suggested in other studies). For the various frames, the calculated U-factors were found to be quite comparable (the maximum difference between the reference CFD simulation and the other simulations was found to be 13.2 percent). A maximum difference of 8.5 percent was found between the CFD simulation and the FEM simulation using ISO 15099 procedures. The ISO 15099 correlation works best for frames with high U-factors. For more efficient frames, the relative differences among various simulations are larger. Temperature was also compared, at selected locations on the frames. Small differences was found in the results from model to model. Finally, the effectiveness of the ISO cavity radiation algorithms was examined by comparing results from these algorithms to detailed radiation calculations (from both programs). Our results suggest that improvements in cavity heat transfer calculations can be obtained by using detailed radiation modeling (i.e. view-factor or ray-tracing models), and that incorporation of these strategies may be more important for improving the accuracy of results than the use of CFD modeling for horizontal cavities.

Gustavsen, Arlid; Kohler, Christian; Dalehaug, Arvid; Arasteh, Dariush

2008-12-01T23:59:59.000Z

254

A Novel Approach For the Simulation of Multiple Flow Mechanisms and Porosities in Shale Gas Reservoirs  

E-Print Network [OSTI]

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

2013-07-15T23:59:59.000Z

255

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.

1981-01-01T23:59:59.000Z

256

Similarity flow solutions of a non-Newtonian power-law fluid Mohamed Guedda, Zakia Hammouch  

E-Print Network [OSTI]

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

257

Application of x-ray microtomography to environmental fluid flow D. Wildenschild*a,c  

E-Print Network [OSTI]

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

258

Numerical modeling of heat transfer and fluid flow in rotor-stator cavities with throughflow  

E-Print Network [OSTI]

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

Boyer, Edmond

259

Hydrothermal dolomites in SW Sardinia (Italy): evidence for a widespread late-Variscan fluid flow event  

E-Print Network [OSTI]

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

260

A conservative Lagrangian scheme for solving compressible fluid flows with multiple internal energy equations  

E-Print Network [OSTI]

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

Note: This page contains sample records for the topic "fluid flow simulation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Coating Flows of Non-Newtonian Fluids: Weakly and Strongly Elastic Limits  

E-Print Network [OSTI]

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

262

Determination of petroleum pipe scale solubility in simulated lung fluid  

E-Print Network [OSTI]

??????. 18 13 Teflon? filter holder (unassembled and assembled)????????.... 21 14 Dissolution experiment setup?????????????????.... 22 15 Curve showing the dissolution profile of barium released from scale... done to determine the solubility of pipe scale in human gastrointestinal fluid (Raabe 1996). Through this work and others, it has been shown that barium sulfate scale is extremely insoluble, even in harsh acidic environments. Based on these results...

Cezeaux, Jason Roderick

2005-08-29T23:59:59.000Z

263

Dynamics of a confined dusty fluid in a sheared ion flow  

SciTech Connect (OSTI)

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)

2014-07-15T23:59:59.000Z

264

Device and method for measuring multi-phase fluid flow in a conduit having an abrupt gradual bend  

DOE Patents [OSTI]

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.

Ortiz, M.G.

1998-02-10T23:59:59.000Z

265

Numerical and experimental study of expiratory flow in the case of major upper airway obstructions with fluid-structure interaction  

E-Print Network [OSTI]

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

266

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

267

Flow of mantle fluids through the ductile lower crust: Heliumisotope trends  

SciTech Connect (OSTI)

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.

2007-10-07T23:59:59.000Z

268

Exact Solutions for a Rotational Flow of Generalized Second Grade Fluids Through a Circular Cylinder  

E-Print Network [OSTI]

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

2008-02-26T23:59:59.000Z

269

Simulation of Complex Fluids using Dissipative Particle Dynamics  

E-Print Network [OSTI]

... Dynamics Abstract: Dissipative Particle Dynamics (DPD) is a relatively new mesoscopic method particularly suitable for simulating biopolymers. It is a coarsed...

270

Numerical modeling of fluid flow and time-lapse seismics to monitor ...  

E-Print Network [OSTI]

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.

santos

271

FRAC-STIM: A Physics-Based Fracture Simulation, /reservoir Flow...  

Broader source: Energy.gov (indexed) [DOE]

FRAC-STIM: A Physics-Based Fracture Simulation, reservoir Flow and Heat Transport Simulator(aka FALCON) FRAC-STIM: A Physics-Based Fracture Simulation, reservoir Flow and Heat...

272

Investigation of aluminum surface cleaning using cavitating fluid flow  

SciTech Connect (OSTI)

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; Strika, Vytautas; Mokin, Vadim [Vilnius Gediminas Technical University, Faculty of Mechanics, Department of Machine Engineering, J. Basanavi?iaus str.28, 03224, Vilnius (Lithuania)

2013-12-16T23:59:59.000Z

273

Flow modeling of flat oval ductwork elbows using computational fluid dynamics  

SciTech Connect (OSTI)

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)

1997-12-31T23:59:59.000Z

274

Toward compressed DMD: spectral analysis of fluid flows using sub-Nyquist-rate PIV data  

E-Print Network [OSTI]

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

2014-01-01T23:59:59.000Z

275

Oscillatory motion based measurement method and sensor for measuring wall shear stress due to fluid flow  

DOE Patents [OSTI]

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)

2008-09-02T23:59:59.000Z

276

Non-Invasive Characterization Of A Flowing Multi-Phase Fluid Using Ultrasonic Interferometry  

DOE Patents [OSTI]

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)

2005-11-01T23:59:59.000Z

277

A turnstile mechanism for fronts propagating in fluid flows  

E-Print Network [OSTI]

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

2013-05-22T23:59:59.000Z

278

A MONTE CARLO SIMULATION OF WATER FLOW IN VARIABLY ...  

E-Print Network [OSTI]

A Monte Carlo simulation method is employed to study groundwater flow in variably saturated fractal porous ... Richards' equation which is solved using a hybridized mixed finite element procedure. ... INTRODUCTION ... This conclusion has led to the development of stochastic models for the basic un- ... different soils.

1910-10-30T23:59:59.000Z

279

Simulation of salt migrations in density dependent groundwater flow  

E-Print Network [OSTI]

and uses a finite element method for the simulation of groundwater flow in the lateral (2D) direction (third dimension) a finite difference method is used in the simula- tions. Numerical experiments are done of this thesis is to investigate the possibilities of modelling salt migrations in density dependent groundwater

Vuik, Kees

280

Motion of a Viscoelastic Micellar Fluid Around a Cylinder: Flow and Fracture  

E-Print Network [OSTI]

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

2006-05-25T23:59:59.000Z

Note: This page contains sample records for the topic "fluid flow simulation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Large-eddy simulation of turbulent cavitating flow in a micro channel  

SciTech Connect (OSTI)

Large-eddy simulations (LES) of cavitating flow of a Diesel-fuel-like fluid in a generic throttle geometry are presented. Two-phase regions are modeled by a parameter-free thermodynamic equilibrium mixture model, and compressibility of the liquid and the liquid-vapor mixture is taken into account. The Adaptive Local Deconvolution Method (ALDM), adapted for cavitating flows, is employed for discretizing the convective terms of the Navier-Stokes equations for the homogeneous mixture. ALDM is a finite-volume-based implicit LES approach that merges physically motivated turbulence modeling and numerical discretization. Validation of the numerical method is performed for a cavitating turbulent mixing layer. Comparisons with experimental data of the throttle flow at two different operating conditions are presented. The LES with the employed cavitation modeling predicts relevant flow and cavitation features accurately within the uncertainty range of the experiment. The turbulence structure of the flow is further analyzed with an emphasis on the interaction between cavitation and coherent motion, and on the statistically averaged-flow evolution.

Egerer, Christian P., E-mail: christian.egerer@aer.mw.tum.de; Hickel, Stefan; Schmidt, Steffen J.; Adams, Nikolaus A. [Institute of Aerodynamics and Fluid Mechanics, Technische Universitt Mnchen, Boltzmannstr. 15, 85748 Garching bei Mnchen (Germany)

2014-08-15T23:59:59.000Z

282

J. Non-Newtonian Fluid Mech., 72 (1997) 7386 Start-up of flow of a FENE-fluid through a 4:1:4 constriction in  

E-Print Network [OSTI]

. 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

283

Method and apparatus for optical Doppler tomographic imaging of fluid flow velocity in highly scattering media  

DOE Patents [OSTI]

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)

1999-01-01T23:59:59.000Z

284

Simulations of Turbulent Flows with Strong Shocks and Density Variations  

SciTech Connect (OSTI)

In this report, we present the research efforts made by our group at UCLA in the SciDAC project ???¢????????Simulations of turbulent flows with strong shocks and density variations???¢???????. We use shock-fitting methodologies as an alternative to shock-capturing schemes for the problems where a well defined shock is present. In past five years, we have focused on development of high-order shock-fitting Navier-Stokes solvers for perfect gas flow and thermochemical non-equilibrium flow and simulation of shock-turbulence interaction physics for very strong shocks. Such simulation has not been possible before because the limitation of conventional shock capturing methods. The limitation of shock Mach number is removed by using our high-order shock-fitting scheme. With the help of DOE and TeraGrid/XSEDE super computing resources, we have obtained new results which show new trends of turbulence statistics behind the shock which were not known before. Moreover, we are also developing tools to consider multi-species non-equilibrium flows. The main results are in three areas: (1) development of high-order shock-fitting scheme for perfect gas flow, (2) Direct Numerical Simulation (DNS) of interaction of realistic turbulence with moderate to very strong shocks using super computing resources, and (3) development and implementation of models for computation of mutli-species non-quilibrium flows with shock-fitting codes.

Zhong, Xiaolin

2012-12-13T23:59:59.000Z

285

CFD SIMULATION OF PROPOSED VALIDATION DATA FOR A FLOW PROBLEM RECONFIGURED TO ELIMINATE AN UNDESIRABLE FLOW INSTABILITY  

SciTech Connect (OSTI)

The U. S. Department of Energy (DOE) is supporting the development of a next generation nuclear plant (NGNP), which will be based on a very high temperature reactor (VHTR) design. The VHTR is a single-phase helium-cooled reactor wherein the helium will be heated initially to 750 C and later to temperatures approaching 1000 C. The high temperatures are desired to increase reactor efficiency and to provide a heat source for the manufacture of hydrogen and other applications. While computational fluid dynamics (CFD) has not been used in the past to design or license nuclear reactors in the U. S., it is expected that CFD will be used in the design and safety analysis of forthcoming designs. This is partly because of the maturity of CFD and partly because detailed information is desired of the flow and heat transfer inside the reactor to avoid hot spots and other conditions that might compromise reactor safety. Numerical computations of turbulent flow should be validated against experimental data for flow conditions that contain some or all of the physics expected in the thermal fluid machinery of interest. To this end, a scaled model of a narrow slice of the lower plenum of the prismatic VHTR was constructed and installed in the Idaho National Laboratorys (INL) matched index of refraction (MIR) test facility and data were taken. The data were then studied and compared to CFD calculations to help determine their suitability for validation data. One of the main findings was that the inlet data, which were measured and controlled by calibrated mass flow rotameters and were also measured using detailed stereo particle image velocimetry (PIV) showed considerable discrepancies in mass flow rate between the two methods. The other finding was that a randomly unstable recirculation zone occurs in the flow. This instability has a very significant effect on the flow field in the vicinity of the inlet jets. Because its time scale is long and because it is apparently a random instability, it was deemed undesirable for a validation data set. It was predicted using CFD that by eliminating the first of the four jets, the recirculation zone could be stabilized. The present paper reports detailed results for the three-jet case with comparisons to the four-jet data inasmuch as three-jet data are still unavailable. Hence, the present simulations are true or blind predictions.

Richard W. Johnson; Hugh M. McIlroy

2010-08-01T23:59:59.000Z

286

PERFORMANCE OF FULLY-COUPLED DOMAIN DECOMPOSITION PRECONDITIONERS for FINITE ELEMENT TRANSPORT / REACTION SIMULATIONS1  

E-Print Network [OSTI]

element simulation of strongly coupled fluid flow, heat transfer, and mass transfer with non methods, stabilized finite element methods. 1. INTRODUCTION Modern computational fluid dynamics flows with unstructured mesh finite element methods. These flow problems are characterized by both

Tuminaro, Ray S.

287

DENSE MULTIPHASE FLOW SIMULATION: CONTINUUM MODEL FOR POLY-DISPERSED SYSTEMS USING KINETIC THEORY  

SciTech Connect (OSTI)

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

2011-08-31T23:59:59.000Z

288

Numerical simulation of laminar flow in a curved duct  

SciTech Connect (OSTI)

This paper describes numerical simulations that were performed to study laminar flow through a square duct with a 900 bend. The purpose of this work was two fold. First, an improved understanding was desired of the flow physics involved in the generation of secondary vortical flows in three-dimensions. Second, adaptive gridding techniques for structured grids in three- dimensions were investigated for the purpose of determining their utility in low Reynolds number, incompressible flows. It was also of interest to validate the commercial computer code CFD-ACE. Velocity predictions for both non-adaptive and adaptive grids are compared with experimental data. Flow visualization was used to examine the characteristics of the flow though the curved duct in order to better understand the viscous flow physics of this problem. Generally, moderate agreement with the experimental data was found but shortcomings in the experiment were demonstrated. The adaptive grids did not produce the same level of accuracy as the non-adaptive grid with a factor of four more grid points.

Lopez, A.R.; Oberkampf, W.L.

1995-01-01T23:59:59.000Z

289

On the 3D steady flow of a second grade fluid past an obstacle  

E-Print Network [OSTI]

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

2010-10-29T23:59:59.000Z

290

Numerical method for fluid flow and heat transfer in magnetohydrodynamic flow  

SciTech Connect (OSTI)

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.

1989-03-01T23:59:59.000Z

291

Ad hoc continuum-atomistic thermostat for modeling heat flow in molecular dynamics simulations  

E-Print Network [OSTI]

Ad hoc continuum-atomistic thermostat for modeling heat flow in molecular dynamics simulations J 2004) An ad hoc thermostating procedure that couples a molecular dynamics (MD) simulation

Brenner, Donald W.

292

Numerical simulation of water flow around a rigid fishing net  

E-Print Network [OSTI]

This paper is devoted to the simulation of the flow around and inside a rigid axisymmetric net. We describe first how experimental data have been obtained. We show in detail the modelization. The model is based on a Reynolds Averaged Navier-Stokes turbulence model penalized by a term based on the Brinkman law. At the out-boundary of the computational box, we have used a "ghost" boundary condition. We show that the corresponding variational problem has a solution. Then the numerical scheme is given and the paper finishes with numerical simulations compared with the experimental data.

Roger Lewandowski; Graldine Pichot

2006-12-20T23:59:59.000Z

293

Corrosion performances in simulated body fluids and cytotoxicity evaluation of Fe-based bulk metallic glasses  

E-Print Network [OSTI]

Corrosion performances in simulated body fluids and cytotoxicity evaluation of Fe-based bulk December 2011 Available online 27 December 2011 Keywords: Bulk metallic glass Corrosion Biocompatibility Electrochemical characterization Biomedical applications The aim of this work is to investigate the corrosion

Zheng, Yufeng

294

Fluid-Structure Interaction Simulations of a Tension-Cone Inflatable Aerodynamic Decelerator  

E-Print Network [OSTI]

Fluid-Structure Interaction Simulations of a Tension-Cone Inflatable Aerodynamic Decelerator of an aerodynamic tension-cone supersonic decelerator prototype intended for large mass payload deploy- ment. Introduction The concept of the inflatable aerodynamic decelerator (IAD) was first proposed in the 1960's

Cirak, Fehmi

295

Two-Dimensional Computational Fluid Dynamics and Conduction Simulations of Heat Transfer in Window Frames  

E-Print Network [OSTI]

1 Two-Dimensional Computational Fluid Dynamics and Conduction Simulations of Heat Transfer Arasteh and Dragan Curcija ABSTRACT Accurately analyzing heat transfer in window frame cavities radiation heat-transfer effects.) We examine three representative complex cavity cross-section profiles

296

Precise simulation of criticality in asymmetric fluids G. Orkoulas, Michael E. Fisher, and A. Z. Panagiotopoulos  

E-Print Network [OSTI]

. Simulations of the heat capacity CV(T, ) and d2 p /dT2 , where p is the vapor pressure below Tc , suggest. INTRODUCTION Liquid-vapor and liquid-liquid phase separation and the related critical behavior in real fluids and liquid phases coexist. As Yang and Yang 2 pointed out in 1964, such a divergence is forbidden

297

Fluid Simulation as a Tool for Painterly Rendering Sven C. Olsen  

E-Print Network [OSTI]

Fluid Simulation as a Tool for Painterly Rendering Sven C. Olsen Swarthmore College Bruce A fields in the context of stroke based non- photorealistic rendering allows us to produce stroke behaviors a painterly rendering system very similar to that in [Litwinowicz 1997]. We can create animations based

Maxwell, Bruce

298

MultiFLIP for Energetic Two-Phase Fluid Simulation LANDON BOYD  

E-Print Network [OSTI]

MultiFLIP for Energetic Two-Phase Fluid Simulation LANDON BOYD and ROBERT BRIDSON University- ing up interesting behaviour. We present a new method which treats both air and liquid., ACM, Inc., 2 Penn Plaza, Suite 701, New York, NY 10121-0701 USA, fax +1 (212) 869-0481, or permissions

Bridson, Robert

299

A Simple Interface to Computational Fluid Dynamics Programs for Building Environment Simulations  

E-Print Network [OSTI]

. SCI can be easily integrated into new CFD programs. Introduction Advanced building design requests and pressure distributions that are crucial for thermal comfort and building structure designs. TraditionallyA Simple Interface to Computational Fluid Dynamics Programs for Building Environment Simulations

Chen, Qingyan "Yan"

300

A hybrid fluid simulation on the Graphics Processing Unit (GPU)  

E-Print Network [OSTI]

and Computer Graphics. 2 (a) Grid-based (b) Particle-based Fig. 1. Two types of uid simulation. everywhere throughout the uid. Also, particle-based methods can run into stability problems when trying to enforce incompressibility. It is possible to use exact.... In this particular term, it is the uid momentum which is being advected. The mass conservation equation (Equation 2.2) is responsible for enforcing in- compressibility of the uid. It states that the divergence of the uid must be zero everywhere in the uid. One...

Flannery, Rebecca Lynn

2008-10-10T23:59:59.000Z

Note: This page contains sample records for the topic "fluid flow simulation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Simulations of ductile flow in brittle material processing  

SciTech Connect (OSTI)

Research is continuing on the effects of thermal properties of the cutting tool and workpiece on the overall temperature distribution. Using an Eulerian finite element model, diamond and steel tools cutting aluminum have been simulated at various, speeds, and depths of cut. The relative magnitude of the thermal conductivity of the tool and the workpiece is believed to be a primary factor in the resulting temperature distribution in the workpiece. This effect is demonstrated in the change of maximum surface temperatures for diamond on aluminum vs. steel on aluminum. As a preliminary step toward the study of ductile flow in brittle materials, the relative thermal conductivities of diamond on polycarbonate is simulated. In this case, the maximum temperature shifts from the rake face of the tool to the surface of the machined workpiece, thus promoting ductile flow in the workpiece surface.

Luh, M.H.; Strenkowski, J.S.

1988-12-01T23:59:59.000Z

302

Effects of mesh density and flow conditioning in simulating 7-pin wire wrapped fuel pins.  

SciTech Connect (OSTI)

In response to the goals outlined by the U.S. Department of Energy's Global Nuclear Energy Partnership program, Argonne National Laboratory has initiated an effort to create an integrated multi-physics multi-resolution thermal hydraulic simulation tool package for the evaluation of nuclear power plant design and safety. As part of this effort, the applicability of a variety of thermal hydraulic analysis methods for the prediction of heat transfer and fluid dynamics in the wire-wrapped fuel-rod bundles found in a fast reactor core is being evaluated. The work described herein provides an initial assessment of the capabilities of the general purpose commercial computational fluid dynamics code Star-CD for the prediction of fluid dynamic characteristics in a wire wrapped fast reactor fuel assembly. A 7-pin wire wrapped fuel rod assembly based on the dimensions of fuel elements in the concept Advanced Burner Test Reactor [1] was simulated for different mesh densities and domain configurations. A model considering a single axial span of the wire wrapped fuel assembly was initially used to assess mesh resolution effects. The influence of the inflow/outflow boundary conditions on the predicted flow fields in the single-span model were then investigated through comparisons with the central span region of models which included 3 and 5 spans. The change in grid refinement had minimal impact on the inter-channel exchange within the assembly resulting in roughly a 5 percent maximum difference. The central span of the 3-span and 5-span cases exhibits much higher velocities than the single span case,, with the largest deviation (15 to 20 percent) occurring furthest away from the wire spacer grids in the higher velocity regions. However, the differences between predicted flow fields in the 3-span and 5-span models are minimal.

Smith, J. G.; Babin, B. R.; Pointer, W. D.; Fischer, P. F. (Mathematics and Computer Science); ( NE); (Kansas State Univ.)

2008-01-01T23:59:59.000Z

303

Computer Simulation of Reservoir Depletion and Oil Flow from the Macondo Well Following the Deepwater  

E-Print Network [OSTI]

Computer Simulation of Reservoir Depletion and Oil Flow from the Macondo Well Following, 2010, Computer simulation of reservoir depletion and oil flow from the Macondo well following. ..................................................................................12 Figures Figure 1. Oblique schematic view of the M56 oil reservoir

304

The influence of fluid flow through granitic crust: a thermo-tectonic study in and on Mont Blanc  

E-Print Network [OSTI]

The influence of fluid flow through granitic crust: a thermo-tectonic study in and on Mont Blanc Tim Dempster, Cristina Persano and Zoe Shipton *Tim.Dempster@ges.gla.ac.uk Granitic and gneissose within a evolving mountain zone, the metasomatic influence of fluids in granite gneiss and the resulting

Glasgow, University of

305

A photographic study of fluid flow theory for two-dimensional laminar flow around solid bodies  

E-Print Network [OSTI]

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

1966-01-01T23:59:59.000Z

306

A Unified Multi-Scale Model for Pore-Scale Flow Simulations in Soils  

SciTech Connect (OSTI)

Pore-scale simulations have received increasing interest in subsurface sciences to provide mechanistic insights into the macroscopic phenomena of water flow and reactive transport processes. The application of the pore scale simulations to soils and sediments is, however, challenged because of the characterization limitation that often only allows partial resolution of pore structure and geometry. A significant proportion of the pore space in soils and sediments is below the spatial resolution, forming a mixed media of pore and porous domains. Here we reported a unified multi-scale model (UMSM) that can be used to simulate water flow and transport in mixed media of pore and porous domains under both saturated and unsaturated conditions. The approach modifies the classic Navier-Stokes equation by adding a Darcy term to describe fluid momentum and uses a generalized mass balance equation for saturated and unsaturated conditions. By properly defining physical parameters, the UMSM can be applied in both pore and porous domains. This paper describes the set of equations for the UMSM, a series of validation cases under saturated or unsaturated conditions, and a real soil case for the application of the approach.

Yang, Xiaofan; Liu, Chongxuan; Shang, Jianying; Fang, Yilin; Bailey, Vanessa L.

2014-01-30T23:59:59.000Z

307

Numerical Simulation of the Flow Field in 3D Eccentric Annular and 2D Centered Labyrinth Seals for Comparison with Experimental LDA Data  

E-Print Network [OSTI]

The flow field in an annular seal is simulated for synchronous circular whirl orbits with 60Hz whirl frequency and a clearance/radius ratio of 0.0154 using the Fluent Computational Fluid Dynamics (CFD) code. Fluent's Moving Reference Frame model...

Vijaykumar, Anand

2011-02-22T23:59:59.000Z

308

Visco-elastic fluid simulations of coherent structures in strongly coupled dusty plasma medium  

SciTech Connect (OSTI)

A generalized hydrodynamic model depicting the behaviour of visco-elastic fluids has often been invoked to explore the behaviour of a strongly coupled dusty plasma medium below their crystallization limit. The model has been successful in describing the collective normal modes of the strongly coupled dusty plasma medium observed experimentally. The paper focuses on the study of nonlinear dynamical characteristic features of this model. Specifically, the evolution of coherent vorticity patches is being investigated here within the framework of this model. A comparison with Newtonian fluids and molecular dynamics simulations treating the dust species interacting through the Yukawa potential has also been presented.

Singh Dharodi, Vikram; Kumar Tiwari, Sanat; Das, Amita, E-mail: amita@ipr.res.in [Institute for Plasma Research, Bhat, Gandhinagar 382428 (India)

2014-07-15T23:59:59.000Z

309

Computational Fluid Dynamics Modeling of the Bonneville Project: Tailrace Spill Patterns for Low Flows and Corner Collector Smolt Egress  

SciTech Connect (OSTI)

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.

2010-12-01T23:59:59.000Z

310

Viscous potential flow analysis of electrified miscible finitely conducting fluid through porous media  

SciTech Connect (OSTI)

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)

2013-04-15T23:59:59.000Z

311

Preferential mode of gas invasion in sediments : grain-scale model of coupled multiphase fluid flow and sediment mechanics  

E-Print Network [OSTI]

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

2009-01-01T23:59:59.000Z

312

Multiphase Fluid Flow in Deformable Variable-Aperture Fractures - Final Report  

SciTech Connect (OSTI)

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

2014-04-30T23:59:59.000Z

313

Molecular modelling and simulation of the surface tension of real quadrupolar fluids  

E-Print Network [OSTI]

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 Stbener; Peter Klein; Karl-Heinz Kfer; Martin Horsch; Hans Hasse

2014-08-21T23:59:59.000Z

314

Molecular modelling and simulation of the surface tension of real quadrupolar fluids  

E-Print Network [OSTI]

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; Kfer, Karl-Heinz; Horsch, Martin; Hasse, Hans

2014-01-01T23:59:59.000Z

315

Journal of Fluids and Structures 20 (2005) 129140 Blood flow and damage by the roller pumps during  

E-Print Network [OSTI]

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

316

Subcritical Finite-Amplitude Solutions for Plane Couette Flow of Viscoelastic Fluids Alexander N. Morozov and Wim van Saarloos  

E-Print Network [OSTI]

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

van Saarloos, Wim

317

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  

E-Print Network [OSTI]

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

318

Determination of Transport Properties From Flowing Fluid Temperature LoggingIn Unsaturated Fractured Rocks: Theory And Semi-Analytical Solution  

SciTech Connect (OSTI)

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.

2008-08-01T23:59:59.000Z

319

Simulation of High Density Pedestrian Flow: Microscopic Model  

E-Print Network [OSTI]

In recent years modelling crowd and evacuation dynamics has become very important, with increasing huge numbers of people gathering around the world for many reasons and events. The fact that our global population grows dramatically every year and the current public transport systems are able to transport large amounts of people, heightens the risk of crowd panic or crush. Pedestrian models are based on macroscopic or microscopic behaviour. In this paper, we are interested in developing models that can be used for evacuation control strategies. This model will be based on microscopic pedestrian simulation models, and its evolution and design requires a lot of information and data. The people stream will be simulated, based on mathematical models derived from empirical data about pedestrian flows. This model is developed from image data bases, so called empirical data, taken from a video camera or data obtained using human detectors. We consider the individuals as autonomous particles interacting through socia...

Dridi, Mohamed H

2015-01-01T23:59:59.000Z

320

Imaging Fluid Flow in Geothermal Wells Using Distributed Thermal Perturbation Sensing  

SciTech Connect (OSTI)

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.

2010-12-10T23:59:59.000Z

Note: This page contains sample records for the topic "fluid flow simulation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Simulation of conjugate driven cavity flow using a Chebyshev-Multidomain method  

SciTech Connect (OSTI)

The driven cavity problem with a temperature gradient is solved as a conjugate problem and compared with the nonconjugate case. Solid-fluid interface conditions are developed for the Chebyshev-Multidomain method which is used to simulate the coupled system. Steady-state solutions are examined at M = 0.3 for a square-cavity at Re = 350 and Re = 3,200 and for a cylindrical cavity at Re = 350. The results show that there are at least slight conjugate effects under most conditions but these effects are generally confined to the solution of the temperature distribution. Transient solutions at Re = 10{sup 4} show effects on the velocity field due to the chaotic nature of the flow.

Huckaby, E.D.; Catton, I.

1999-07-01T23:59:59.000Z

322

Computer simulation of effective viscosity of fluid-proppant mixture used in hydraulic fracturing  

E-Print Network [OSTI]

The paper presents results of numerical experiments performed to evaluate the effective viscosity of a fluid-proppant mixture, used in hydraulic fracturing. The results, obtained by two complimenting methods (the particle dynamics and the smoothed particle hydrodynamics), coincide to the accuracy of standard deviation. They provide an analytical equation for the dependence of effective viscosity on the proppant concentration, needed for numerical simulation of the hydraulic fracture propagation.

Kuzkin, Vitaly A; Linkov, Aleksandr M

2013-01-01T23:59:59.000Z

323

Fluid flow through very low permeability materials: A concern in the geological isolation of waste  

SciTech Connect (OSTI)

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.

1992-12-31T23:59:59.000Z

324

Optimization of a Two-Fluid Hydrodynamic Model of Churn-Turbulent Flow  

SciTech Connect (OSTI)

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

2009-07-01T23:59:59.000Z

325

High-heat-flux removal by phase-change fluid and particulate flow  

SciTech Connect (OSTI)

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))

1993-07-01T23:59:59.000Z

326

Numerical schemes for dynamically orthogonal equations of stochastic fluid and ocean flows  

SciTech Connect (OSTI)

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: mpuecker@mit.edu [Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Mass. Avenue, Cambridge, MA 02139 (United States); Lermusiaux, P.F.J., E-mail: pierrel@mit.edu [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: sapsis@mit.edu [Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Mass. Avenue, Cambridge, MA 02139 (United States)

2013-01-15T23:59:59.000Z

327

Error estimation and anisotropic mesh refinement for 3d laminar aerodynamic flow simulations  

E-Print Network [OSTI]

Error estimation and anisotropic mesh refinement for 3d laminar aerodynamic flow simulations Tobias Leichta,b , Ralf Hartmann,a,b aInstitute of Aerodynamics and Flow Technology, DLR (German Aerospace Center-dimensional laminar aerodynamic flow simulations. The optimal order symmetric interior penalty discontinuous Galerkin

Hartmann, Ralf

328

Large-eddy simulation of swirling particle-laden flows in a coaxial-jet combustor  

E-Print Network [OSTI]

Large-eddy simulation of swirling particle-laden flows in a coaxial-jet combustor S.V. Apte a,* , K 2003 Abstract Large-eddy simulation (LES) of particle-laden, swirling flow in a coaxial-jet combustor;cyclone combustors, and biomass gasifiers (Lefebvre, 1989). The physics of such flows is extremely complex

Apte, Sourabh V.

329

Hydrodynamical adaptive mesh refinement simulations of turbulent flows - II. Cosmological simulations of galaxy clusters  

E-Print Network [OSTI]

The development of turbulent gas flows in the intra-cluster medium and in the core of a galaxy cluster is studied by means of adaptive mesh refinement (AMR) cosmological simulations. A series of six runs was performed, employing identical simulation parameters but different criteria for triggering the mesh refinement. In particular, two different AMR strategies were followed, based on the regional variability of control variables of the flow and on the overdensity of subclumps, respectively. We show that both approaches, albeit with different results, are useful to get an improved resolution of the turbulent flow in the ICM. The vorticity is used as a diagnostic for turbulence, showing that the turbulent flow is not highly volume-filling but has a large area-covering factor, in agreement with previous theoretical expectations. The measured turbulent velocity in the cluster core is larger than 200 km/s, and the level of turbulent pressure contribution to the cluster hydrostatic equilibrium is increased by using the improved AMR criteria.

L. Iapichino; J. C. Niemeyer

2008-07-01T23:59:59.000Z

330

U-Sr isotopic speedometer: Fluid flow and chemical weatheringrates inaquifers  

SciTech Connect (OSTI)

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.

2005-12-27T23:59:59.000Z

331

Multiparticle imaging technique for two-phase fluid flows using pulsed laser speckle velocimetry  

SciTech Connect (OSTI)

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.

1992-12-01T23:59:59.000Z

332

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  

SciTech Connect (OSTI)

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.

2013-04-29T23:59:59.000Z

333

Numerical simulations of the Macondo well blowout reveal strong control of oil flow by reservoir permeability and exsolution of gas  

E-Print Network [OSTI]

for estimates of the oil and gas flow rate from the Macondoteam and carried out oil and gas flow simulations using theoil-gas system. The flow of oil and gas was simulated using

Oldenburg, C.M.

2013-01-01T23:59:59.000Z

334

A multiple temperature kinetic model and its application to micro-scale gas flow simulations  

E-Print Network [OSTI]

A multiple temperature kinetic model and its application to micro-scale gas flow simulations model, micro-scale flows. 1. Introduction Gas flows can be classified according to the flow regimes_pku@yahoo.com.cn Abstract This paper presents a numerical approach to solve the multiple temperature kinetic model (MTKM

Xu, Kun

335

Automation cueing modulates cerebral blood flow and vigilance in a simulated air traffic control task  

E-Print Network [OSTI]

Automation cueing modulates cerebral blood flow and vigilance in a simulated air traffic control: Automation; vigilance; cerebral blood flow; mental workload; attentional resources. Automation cueing operator, depending on automation reliability. To assess these effects, transcranial Doppler sonography

Parasuraman, Raja

336

Numerical simulation of flow distribution for pebble bed high temperature gas cooled reactors  

E-Print Network [OSTI]

?....................................................................................26 V CFD MODELLING ...................................................................................28 V.1 Computational Fluid Dynamics (CFD) ..........................................28 V.2 The History.... Hassan The premise of the work presented here is to use a common analytical tool, Computational Fluid Dynamics (CFD), along with different turbulence models. Eddy viscosity models as well as state-of-the-art Large Eddy Simulation (LES) were...

Yesilyurt, Gokhan

2004-09-30T23:59:59.000Z

337

Simulations of amphiphilic fluids using mesoscale lattice-Boltzmann and lattice-gas methods  

E-Print Network [OSTI]

We compare two recently developed mesoscale models of binary immiscible and ternary amphiphilic fluids. We describe and compare the algorithms in detail and discuss their stability properties. The simulation results for the cases of self-assembly of ternary droplet phases and binary water-amphiphile sponge phases are compared and discussed. Both models require parallel implementation and deployment on large scale parallel computing resources in order to achieve reasonable simulation times for three-dimensional models. The parallelisation strategies and performance on two distinct parallel architectures are compared and discussed. Large scale three dimensional simulations of multiphase fluids requires the extensive use of high performance visualisation techniques in order to enable the large quantities of complex data to be interpreted. We report on our experiences with two commercial visualisation products: AVS and VTK. We also discuss the application and use of novel computational steering techniques for the more efficient utilisation of high performance computing resources. We close the paper with some suggestions for the future development of both models.

P. J. Love; M. Nekovee; J. Chin; N. Gonzalez-Segredo; P. V. Coveney

2002-12-06T23:59:59.000Z

338

Similarity Flow Solutions of a Non-Newtonian Power-law Fluid  

E-Print Network [OSTI]

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

2009-01-01T23:59:59.000Z

339

Large-Eddy Simulation of the Bachalo-Johnson Flow, with Shock...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Travin, New Technologies and Services, Ltd. Large-Eddy Simulation of the Bachalo-Johnson Flow, with Shock-Induced Separation PI Name: Philippe Spalart PI Email:...

340

High Performance Computing Based Methods for Simulation and Optimisation of Flow Problems.  

E-Print Network [OSTI]

??The thesis is concerned with the study of methods in high-performance computing for simulation and optimisation of flow problems that occur in the framework of (more)

Bockelmann, Hendryk

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "fluid flow simulation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Nanometer-scale imaging and pore-scale fluid flow modeling inchalk  

SciTech Connect (OSTI)

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

2005-08-23T23:59:59.000Z

342

Lattice Boltzmann simulations of liquid crystalline fluids: active gels and blue phases  

E-Print Network [OSTI]

Lattice Boltzmann simulations have become a method of choice to solve the hydrodynamic equations of motion of a number of complex fluids. Here we review some recent applications of lattice Boltzmann to study the hydrodynamics of liquid crystalline materials. In particular, we focus on the study of (a) the exotic blue phases of cholesteric liquid crystals, and (b) active gels - a model system for actin plus myosin solutions or bacterial suspensions. In both cases lattice Boltzmann studies have proved useful to provide new insights into these complex materials.

M. E. Cates; O. Henrich; D. Marenduzzo; K. Stratford

2010-09-06T23:59:59.000Z

343

Thickness-based adaptive mesh refinement methods for multi-phase flow simulations with thin regions  

SciTech Connect (OSTI)

In numerical simulations of multi-scale, multi-phase flows, grid refinement is required to resolve regions with small scales. A notable example is liquid-jet atomization and subsequent droplet dynamics. It is essential to characterize the detailed flow physics with variable length scales with high fidelity, in order to elucidate the underlying mechanisms. In this paper, two thickness-based mesh refinement schemes are developed based on distance- and topology-oriented criteria for thin regions with confining wall/plane of symmetry and in any situation, respectively. Both techniques are implemented in a general framework with a volume-of-fluid formulation and an adaptive-mesh-refinement capability. The distance-oriented technique compares against a critical value, the ratio of an interfacial cell size to the distance between the mass center of the cell and a reference plane. The topology-oriented technique is developed from digital topology theories to handle more general conditions. The requirement for interfacial mesh refinement can be detected swiftly, without the need of thickness information, equation solving, variable averaging or mesh repairing. The mesh refinement level increases smoothly on demand in thin regions. The schemes have been verified and validated against several benchmark cases to demonstrate their effectiveness and robustness. These include the dynamics of colliding droplets, droplet motions in a microchannel, and atomization of liquid impinging jets. Overall, the thickness-based refinement technique provides highly adaptive meshes for problems with thin regions in an efficient and fully automatic manner.

Chen, Xiaodong [The State Key Laboratory of Nonlinear Mechanics, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190 (China); Yang, Vigor, E-mail: vigor.yang@aerospace.gatech.edu [School of Aerospace Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0150 (United States)

2014-07-15T23:59:59.000Z

344

Three-Dimensional Simulation of Forebay and Turbine Intakes Flows for the Bonneville Project  

SciTech Connect (OSTI)

Natural resource applications of computational fluid dynamics (CFD) models are becoming more frequent with the advances in computational power and the availability of commercial meshing software and verified CFD solver applications. The Bonneville Lock and Dam Project, constructed and operated by the U. S. Army Corps of Engineers, is the westernmost dam on the Columbia River, and is located about 40 miles upstream of Portland, Oregon. A set of 3D CFD models have been developed for the Bonneville Project forebay and turbine intakes; the CFD models provide a tool to predict the impact of proposed changes in operational rules both for the overall river flow patterns and near the turbine intakes. These models also offer rapid insight into the performance of proposed or existing hydraulic structures. The creation of a computational domain for Bonneville was complex and required the use of many software tools to integrate the diverse data sources that described the river and powerhouse geometry into a single computational domain. Once the computational mesh was created, flows were simulated by solving the Reynolds-averaged Navier-Stokes (RANS) equations together with a two-equation (k-epsilon) turbulence model. The model was validated using velocity data measured in reduced scale physical models and in the field.

Rakowski, Cynthia L.; Richmond, Marshall C.; Serkowski, John A.; Ebner, Laurie L.

2002-12-31T23:59:59.000Z

345

High Fidelity Simulation of Complex Suspension Flow for Practical...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

designs of concrete are developed to meet these needs, it is important to measure and control flow properties to satisfy performance specifications. Failure to control the flow...

346

Method and apparatus for balancing discharge fluid flow in drilling mud treatment units  

SciTech Connect (OSTI)

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.

1983-03-29T23:59:59.000Z

347

Ice Shelves as Floating Channel Flows of Viscous Power-Law Fluids  

E-Print Network [OSTI]

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

2013-01-01T23:59:59.000Z

348

Magnetic fabrics and fluid flow directions in hydrothermal systems. A case study in the Chaillac BaFFe deposits  

E-Print Network [OSTI]

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

Paris-Sud XI, Université de

349

Modeling-Computer Simulations At Long Valley Caldera Geothermal...  

Open Energy Info (EERE)

Modeling-Computer Simulations Activity Date - 2003 Usefulness not indicated DOE-funding Unknown Notes Several fluid-flow models presented regarding the Long Valley Caldera....

350

LATEX TikZposter Simulation of two-phase flow for  

E-Print Network [OSTI]

Aachen University Simulation of two-phase flow for direct steam-generating solar thermal power plantsLATEX TikZposter Simulation of two-phase flow for direct steam-generating solar thermal power University Concentrating solar thermal power plants Concentrating solar thermal power (CSP) plants

Ábrahám, Erika

351

Friction dependence of shallow granular flows from discrete par-ticle simulations  

E-Print Network [OSTI]

Friction dependence of shallow granular flows from discrete par- ticle simulations Anthony Thornton relation for the macroscopic bed friction or basal roughness obtained from micro-scale discrete particle simulations of steady flows. We systematically vary the bed friction by changing the contact friction

Al Hanbali, Ahmad

352

Comparison of Numerical Techniques Used for Simulating Variable-Density Flow and Transport Experiments  

E-Print Network [OSTI]

Comparison of Numerical Techniques Used for Simulating Variable-Density Flow and Transport code by simulating two new variable-density-flow and transport experimental data sets. The experiments transport of a sinking groundwater plume and a rising groundwater plume. The numerical techniques used

Clement, Prabhakar

353

Evaluation of a CFD-model for simulation of simplified flow conditioners  

SciTech Connect (OSTI)

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)

1995-12-31T23:59:59.000Z

354

Some Specific CASL Requirements for Advanced Multiphase Flow Simulation of Light Water Reactors  

SciTech Connect (OSTI)

Because of the diversity of physical phenomena occuring in boiling, flashing, and bubble collapse, and of the length and time scales of LWR systems, it is imperative that the models have the following features: Both vapor and liquid phases (and noncondensible phases, if present) must be treated as compressible. Models must be mathematically and numerically well-posed. The models methodology must be multi-scale. A fundamental derivation of the multiphase governing equation system, that should be used as a basis for advanced multiphase modeling in LWR coolant systems, is given in the Appendix using the ensemble averaging method. The remainder of this work focuses specifically on the compressible, well-posed, and multi-scale requirements of advanced simulation methods for these LWR coolant systems, because without these are the most fundamental aspects, without which widespread advancement cannot be claimed. Because of the expense of developing multiple special-purpose codes and the inherent inability to couple information from the multiple, separate length- and time-scales, efforts within CASL should be focused toward development of a multi-scale approaches to solve those multiphase flow problems relevant to LWR design and safety analysis. Efforts should be aimed at developing well-designed unified physical/mathematical and high-resolution numerical models for compressible, all-speed multiphase flows spanning: (1) Well-posed general mixture level (true multiphase) models for fast transient situations and safety analysis, (2) DNS (Direct Numerical Simulation)-like models to resolve interface level phenmena like flashing and boiling flows, and critical heat flux determination (necessarily including conjugate heat transfer), and (3) Multi-scale methods to resolve both (1) and (2) automatically, depending upon specified mesh resolution, and to couple different flow models (single-phase, multiphase with several velocities and pressures, multiphase with single velocity and pressure, etc.) A unified, multi-scale approach is advocated to extend the necessary foundations and build the capability to simultaneously solve the fluid dynamic interface problems (interface resolution) as well as multiphase mixtures (homogenization).

R. A. Berry

2010-11-01T23:59:59.000Z

355

Numerical simulations of heat transfer in plane channel flow Najla EL GHARBI 1, 3, a  

E-Print Network [OSTI]

Numerical simulations of heat transfer in plane channel flow Najla EL GHARBI 1, 3, a , Rafik ABSI 2 abenzaoui@gmail.com Keywords: turbulent flows, heat transfer, forced convection, low Reynolds number model data for Re = 150. Introduction Turbulent flow with heat transfer mechanism is of great importance from

Paris-Sud XI, Université de

356

Steam generators two phase flows numerical simulation with liquid and gas momentum equations  

E-Print Network [OSTI]

Steam generators two phase flows numerical simulation with liquid and gas momentum equations M Abstract This work takes place in steam generators flow studies and we consider here steady state three words: Steam Generator, Two-phase Flow, Finite element Email address: Marc.Grandotto@cea.fr (M

Paris-Sud XI, Université de

357

Turbulence prediction in two- and three-dimensional bundle flows using Large Eddy Simulation  

E-Print Network [OSTI]

TURBULENCE PREDICTION IN TWO- AND THREE-DIMENSIONAL BUNDLE FLOWS USING LARGE EDDY SIMULATION A Thesis by WAEL ABDUL-HAMID IBRAHIM Submitted to Texas A&M University in partial fulfillment of the requirements for the degree of MASTER... Prediction in Two- and Three-Dimensional Bundle Flows Using Large Eddy Simulation. (May 1994) Wael Abdul-Hamid Ibrahim, B. S. Alexandria University Chair of Advisory Committee: Dr. Yassin A. Hassan Flow turbulence is a familiar phenomenon in everyday life...

Ibrahim, Wael Abdul-Hamid

1994-01-01T23:59:59.000Z

358

Flume studies of sediment transportation in shallow flow with simulated rainfall  

E-Print Network [OSTI]

force exerted on a particle by flowing water, which according to Newton, was equal to Trr V 2 where s is a shape factor (0. 79 for spheres), g is the specific weight s of the particle, r is its radius, and V is the critical bottom velocity. cr... water pipe flow . Turbulent flow can be visualized as being divided into sheets of fluid having one velocity. These sheets are traversed by eddies, and in this manner the flow tends to establish a condition of equilibrium by a mixing process...

Nail, Frank Mitchell

2012-06-07T23:59:59.000Z

359

Application of Multi-rate Flowing Fluid Electric ConductivityLogging Method to Well DH-2, Tono Site, Japan  

SciTech Connect (OSTI)

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

2004-10-04T23:59:59.000Z

360

Analysis of turbulent transport and mixing in transitional Rayleigh/Taylor unstable flow using direct numerical simulation data  

DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

Data from a 1152X760X1280 direct numerical simulation (DNS) [N. J. Mueschke and O. Schilling, Phys. Fluids 21, 014106 (2009)] of a transitional Rayleigh-Taylor mixing layer modeled after a small Atwood number water channel experiment is used to comprehensively investigate the structure of mean and turbulent transport and mixing. The simulation had physical parameters and initial conditions approximating those in the experiment. The budgets of the mean vertical momentum, heavy-fluid mass fraction, turbulent kinetic energy, turbulent kinetic energy dissipation rate, heavy-fluid mass fraction variance, and heavy-fluid mass fraction variance dissipation rate equations are constructed using Reynolds averaging applied to the DNS data. The relative importance of mean and turbulent production, turbulent dissipation and destruction, and turbulent transport are investigated as a function of Reynolds number and across the mixing layer to provide insight into the flow dynamics not presently available from experiments. The analysis of the budgets supports the assumption for small Atwood number, Rayleigh/Taylor driven flows that the principal transport mechanisms are buoyancy production, turbulent production, turbulent dissipation, and turbulent diffusion (shear and mean field production are negligible). As the Reynolds number increases, the turbulent production in the turbulent kinetic energy dissipation rate equation becomes the dominant production term, while the buoyancy production plateaus. Distinctions between momentum and scalar transport are also noted, where the turbulent kinetic energy and its dissipation rate both grow in time and are peaked near the center plane of the mixing layer, while the heavy-fluid mass fraction variance and its dissipation rate initially grow and then begin to decrease as mixing progresses and reduces density fluctuations. All terms in the transport equations generally grow or decay, with no qualitative change in their profile, except for the pressure flux contribution to the total turbulent kinetic energy flux, which changes sign early in time (a countergradient effect). The production-to-dissipation ratios corresponding to the turbulent kinetic energy and heavy-fluid mass fraction variance are large and vary strongly at small evolution times, decrease with time, and nearly asymptote as the flow enters a self-similar regime. The late-time turbulent kinetic energy production-to-dissipation ratio is larger than observed in shear-driven turbulent flows. The order of magnitude estimates of the terms in the transport equations are shown to be consistent with the DNS at late-time, and also confirms both the dominant terms and their evolutionary behavior. These results are useful for identifying the dynamically important terms requiring closure, and assessing the accuracy of the predictions of Reynolds-averaged Navier-Stokes and large-eddy simulation models of turbulent transport and mixing in transitional Rayleigh-Taylor instability-generated flow.

Schilling, Oleg [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States); Mueschke, Nicholas J. [Texas A and M Univ., College Station, TX (United States)

2010-10-18T23:59:59.000Z

Note: This page contains sample records for the topic "fluid flow simulation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

L-H transition dynamics in fluid turbulence simulations with neoclassical force balance  

SciTech Connect (OSTI)

Spontaneous transport barrier generation at the edge of a magnetically confined plasma is reproduced in flux-driven three-dimensional fluid simulations of electrostatic turbulence. Here, the role on the radial electric field of collisional friction between trapped and passing particles is shown to be the key ingredient. Especially, accounting for the self-consistent and precise dependence of the friction term on the actual plasma temperature allows for the triggering of a transport barrier, provided that the input power exceeds some threshold. In addition, the barrier is found to experience quasi-periodic relaxation events, reminiscent of edge localised modes. These results put forward a possible key player, namely, neoclassical physics via radial force balance, for the low- to high-confinement regime transition observed in most of controlled fusion devices.

Chn, L. [AixMarseille Universit, CNRS, PIIM UMR 7345, 13397 Marseille Cedex 20 (France); CEA, IRFM, F-13108 Saint-Paul-lez-Durance (France); Beyer, P.; Fuhr, G.; Benkadda, S. [AixMarseille Universit, CNRS, PIIM UMR 7345, 13397 Marseille Cedex 20 (France); Sarazin, Y.; Bourdelle, C. [CEA, IRFM, F-13108 Saint-Paul-lez-Durance (France)

2014-07-15T23:59:59.000Z

362

Numerical simulation of three-dimensional electrical flow through geomaterials  

E-Print Network [OSTI]

components in different arrangements (Mitchell 1993; Shang et al. 1995). These are very simple models and have been verified by experiments that consider only one-dimensional flow of current. In actual practice, current flow is three-dimensional around... the source. Methods do not exist to analyze three-dimensional current flow through circuit elements other than resistors. Thus, there is a need to develop methods to overcome these shortcomings. Electrical cone penetrometers have been used to convey...

Akhtar, Anwar Saeed

1998-01-01T23:59:59.000Z

363

CSE IGERTCOMPUTATIONAL SCIENCE AND ENGINEERING IGERT QUARTERLy NEwSLETTER Simulations of a two-component fluid (left) using a phase field  

E-Print Network [OSTI]

CSE IGERTCOMPUTATIONAL SCIENCE AND ENGINEERING IGERT QUARTERLy NEwSLETTER Simulations of a two-component fluid (left) using a phase field model with dynamic adaptive mesh refinement (right). Hector Ceniceros patterns when a less viscous fluid (dyed water in the image) is injected into a more viscous fluid (clear

Bigelow, Stephen

364

The Effect of High Rotational Speed on the Performance of Straight-through Labyrinth Seals for Compressible and Incompressible Flow  

E-Print Network [OSTI]

The leakage flow through straight through labyrinth seals with tooth on stator was investigated by performing CFD simulations .ANSYS Fluent is used to simulate the fluid flow through straight through Labyrinth seals. The effect of seal geometry...

Obidigbo, Ekene R.

2012-07-16T23:59:59.000Z

365

Using x-ray microtomography and pore-scale modeling to quantify sediment mixing and fluid flow in a developing streambed  

SciTech Connect (OSTI)

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)

2010-01-22T23:59:59.000Z

366

Characterizing Flow in Oil Reservoir Rock Using Smooth Particle Hydrodynamics  

E-Print Network [OSTI]

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.

367

ORIGINAL PAPER Conditional simulations of wateroil flow in heterogeneous porous  

E-Print Network [OSTI]

water standards. Thus, a small amount of NAPL can contaminate large volumes of groundwater over a long period of time. Therefore, it is very important to understand the processes associated with contaminant is a complicated mixture of hydrocarbon fluids, brine, porous rock and fractures. The structure of the void space

Lu, Zhiming

368

Two-Phase Flow Simulations In a Natural Rock Fracture using the VOF Method  

SciTech Connect (OSTI)

Standard models of two-phase flow in porous media have been shown to exhibit several shortcomings that might be partially overcome with a recently developed model based on thermodynamic principles (Hassanizadeh and Gray, 1990). This alternative two-phase flow model contains a set of new and non-standard parameters, including specific interfacial area. By incorporating interfacial area production, destruction, and propagation into functional relationships that describe the capillary pressure and saturation, a more physical model has been developed. Niessner and Hassanizadeh (2008) have examined this model numerically and have shown that the model captures saturation hysteresis with drainage/imbibition cycles. Several static experimental studies have been performed to examine the validity of this new thermodynamically based approach; these allow the determination of static parameters of the model. To date, no experimental studies have obtained information about the dynamic parameters required for the model. A new experimental porous flow cell has been constructed using stereolithography to study two-phase flow phenomena (Crandall et al. 2008). A novel image analysis tool was developed for an examination of the evolution of flow patterns during displacement experiments (Crandall et al. 2009). This analysis tool enables the direct quantification of interfacial area between fluids by matching known geometrical properties of the constructed flow cell with locations identified as interfaces from images of flowing fluids. Numerous images were obtained from two-phase experiments within the flow cell. The dynamic evolution of the fluid distribution and the fluid-fluid interface locations were determined by analyzing these images. In this paper, we give a brief introduction to the thermodynamically based two-phase flow model, review the properties of the stereolithography flow cell, and show how the image analysis procedure has been used to obtain dynamic parameters for the numerical model. These parameters include production/destruction of interfacial area as a function of saturation and capillary pressure. Our preliminary results for primary drainage in porous media show that the specific interfacial area increased linearly with increasing gas saturation until breakthrough of the displacing gas into the exit manifold occurred.

Crandall, Dustin; Ahmadi, Goodarz; Smith, Duane H., Bromhal, Grant

2010-01-01T23:59:59.000Z

369

Large-Eddy Simulation of Flow and Pollutant Transport in Urban Street Canyons with Ground Heating  

E-Print Network [OSTI]

Our study employed large-eddy simulation (LES) based on a one-equation subgrid-scale model to investigate the flow field and pollutant dispersion characteristics inside urban street canyons. Unstable thermal stratification ...

Li, Xian-Xiang

370

Comparison and Validation of Compressible Flow Simulations of Laser-Induced Cavitation  

E-Print Network [OSTI]

Comparison and Validation of Compressible Flow Simulations of Laser-Induced Cavitation Bubbles)). The validation is performed for the case of laser-induced cavitation bubbles collapsing in an infinite medium

371

Simulation and visualization of fields and energy flows in electric circuits with idealized geometries  

E-Print Network [OSTI]

This thesis develops a method to simulate and visualize the fields and energy flows in electric circuits, using a simplified physical model based on an idealized geometry. The physical models combine and extend previously ...

Ohannessian, Mesrob I., 1981-

2005-01-01T23:59:59.000Z

372

On the influence of an absorption term in incompressible fluid flows  

E-Print Network [OSTI]

|, 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

373

Statistical Estimation of Fluid Flow Fields Johnny Chang David Edwards Yizhou Yu  

E-Print Network [OSTI]

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

374

One-dimensional fluid diffusion induced by constant-rate flow injection: Theoretical analysis and application  

E-Print Network [OSTI]

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

375

Application of X-ray CT for investigating fluid flow and conformance control during CO2 injection in highly heterogeneous media  

E-Print Network [OSTI]

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

2005-08-29T23:59:59.000Z

376

A numerical framework for the direct simulation of solid-fluid systems  

E-Print Network [OSTI]

Our understanding of solid-fluid dynamics has been severely limited by the nonexistence of a high-fidelity modeling capability for these multiphase systems. Continuum modeling approaches overlook the microscale solid-fluid ...

Cook, Benjamin Koger, 1965-

2001-01-01T23:59:59.000Z

377

Edge-based Meshless Methods for Compressible Flow Simulations  

E-Print Network [OSTI]

are obtained for airfoils in transonic flow. Lift and drag coefficients also compare well to the finite volume, including (1) the application of certain artificial diffusion schemes to meshless methods within an edge

Jameson, Antony

378

Simulated Surface-Induced Thrombin Generation in a Flow Field  

E-Print Network [OSTI]

A computational model of blood coagulation is presented with particular emphasis on the regulatory effects of blood flow, spatial distribution of tissue factor (TF), and the importance of the thrombomodulin-activated protein ...

Jordan, S.W.

379

FRACTURING FLUID CHARACTERIZATION FACILITY  

SciTech Connect (OSTI)

Hydraulic fracturing technology has been successfully applied for well stimulation of low and high permeability reservoirs for numerous years. Treatment optimization and improved economics have always been the key to the success and it is more so when the reservoirs under consideration are marginal. Fluids are widely used for the stimulation of wells. The Fracturing Fluid Characterization Facility (FFCF) has been established to provide the accurate prediction of the behavior of complex fracturing fluids under downhole conditions. The primary focus of the facility is to provide valuable insight into the various mechanisms that govern the flow of fracturing fluids and slurries through hydraulically created fractures. During the time between September 30, 1992, and March 31, 2000, the research efforts were devoted to the areas of fluid rheology, proppant transport, proppant flowback, dynamic fluid loss, perforation pressure losses, and frictional pressure losses. In this regard, a unique above-the-ground fracture simulator was designed and constructed at the FFCF, labeled ''The High Pressure Simulator'' (HPS). The FFCF is now available to industry for characterizing and understanding the behavior of complex fluid systems. To better reflect and encompass the broad spectrum of the petroleum industry, the FFCF now operates under a new name of ''The Well Construction Technology Center'' (WCTC). This report documents the summary of the activities performed during 1992-2000 at the FFCF.

Subhash Shah

2000-08-01T23:59:59.000Z

380

Swirling structure for mixing two concentric fluid flows at nozzle outlet  

DOE Patents [OSTI]

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.

1993-07-20T23:59:59.000Z

Note: This page contains sample records for the topic "fluid flow simulation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Low level jet development during a numerically simulated return flow event  

E-Print Network [OSTI]

of the obstacle. This simulation shows that the structure of the lower tropospheric air flow during a period of return flow is complex. When mid-level westerlies are weak, mesoscale processes govern the development of low level jets. As the westerly winds increase...

Igau, Richard Charles

1994-01-01T23:59:59.000Z

382

Simple Models of Zero-Net Mass-Flux Jets for Flow Control Simulations  

E-Print Network [OSTI]

Simple Models of Zero-Net Mass-Flux Jets for Flow Control Simulations Reni Raju Dynaflow Inc for modeling the dynamics of zero- net mass-flux (ZNMF) actuators, the computational costs associated-flow model. 1. INTRODUCTION Zero-net mass-flux (ZNMF) actuators or "synthetic jets" have potential

Mittal, Rajat

383

Simulation of Nondifferentiable Models for Groundwater Flow and C. T. Kelleya  

E-Print Network [OSTI]

1 Simulation of Nondifferentiable Models for Groundwater Flow and Transport C. T. Kelleya K. R frequently in models for groundwater flow and species transport. The van Genuchten and Mualem PSK relations. INTRODUCTION Nonsmooth, even non-Lipschitz continuous, constitutive laws are not uncommon in models

384

Recent Advances in Computational Techniques for Simulation of Flow in Porous Media  

E-Print Network [OSTI]

are also addressed. Introduction Modeling porous media flow processes is required in many science and engineering applications. Oil recovery, environmental hydrology and groundwater flow are a few drivers in the development of porous media simulation tools. Nowadays high resolution models are constructed as a result

Coutinho, Alvaro L. G. A.

385

Numerical analysis of laminar fluid flow and heat transfer in a parallel plate channel with normally in-line positioned plates  

E-Print Network [OSTI]

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

2012-06-07T23:59:59.000Z

386

Level Set Based Simulations of Two-Phase Oil-Water Flows in Pipes  

E-Print Network [OSTI]

application is the lubricated pipelining of crude oil by the addition of water. We want to e?ciently transportLevel Set Based Simulations of Two-Phase Oil-Water Flows in Pipes Hyeseon Shim July 31, 2000 Abstract We simulate the axisymmetric pipeline transportation of oil and water numerically under

Soatto, Stefano

387

Investigation and Simulation of Three--Phase Flow in Porous Media  

E-Print Network [OSTI]

. The first simulator uses the coupled pressure--saturation formulation with a fixed set of primary variables. Contaminants such as petroleum products and other organic compounds which can dissolve in the groundwater in petroleum engineer­ ing where multiphase flow was examined and first numerical simulations had been

Cirpka, Olaf Arie

388

Electrostatics on the sphere with applications to Monte Carlo simulations of two dimensional polar fluids  

E-Print Network [OSTI]

We present two methods for solving the electrostatics of point charges and multipoles on the surface of a sphere, \\textit{i.e.} in the space $\\mathcal{S}_{2}$, with applications to numerical simulations of two-dimensional polar fluids. In the first approach, point charges are associated with uniform neutralizing backgrounds to form neutral pseudo-charges, while, in the second, one instead considers bi-charges, \\textit{i.e.} dumbells of antipodal point charges of opposite signs. We establish the expressions of the electric potentials of pseudo- and bi-charges as isotropic solutions of the Laplace-Beltrami equation in $\\mathcal{S}_{2}$. A multipolar expansion of pseudo- and bi-charge potentials leads to the electric potentials of mono- and bi-multipoles respectively. These potentials constitute non-isotropic solutions of the Laplace-Beltrami equation the general solution of which in spherical coordinates is recast under a new appealing form. We then focus on the case of mono- and bi-dipoles and build the theory...

Caillol, Jean-Michel

2015-01-01T23:59:59.000Z

389

Criterion for purely elastic Taylor-Couette instability in the flows of shear-banding fluids  

E-Print Network [OSTI]

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.

390

Airfoil Shape Optimization for Transonic Flows of BetheZel'dovichThompson Fluids  

E-Print Network [OSTI]

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

Paris-Sud XI, Université de

391

Interfacial exchange relations for two-fluid vapor-liquid flow : a simplified regime map approach  

E-Print Network [OSTI]

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.

1981-01-01T23:59:59.000Z

392

Flow through porous media : from mixing of fluids to triggering of earthquakes  

E-Print Network [OSTI]

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

2014-01-01T23:59:59.000Z

393

A Semi-Lagrangian approach for dilute non-collisional fluid-particle flows  

E-Print Network [OSTI]

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

394

A coupled volume-of-fluid and level set (VOSET) method for computing incompressible two-phase flows  

E-Print Network [OSTI]

& Power Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, PR China a r t i c l e i n f o processes such as chemical reactor, power plant, copper refining and internal combustion engine developed to simulate complex two-phase flow problems. The most important methods include the front tracking

Frey, Pascal

395

Investigating the changes in matrix and fracture properties and fluid flow under different stress-state conditions  

E-Print Network [OSTI]

pressure of 500 psi................................................................33 3.16 The average flow rate comparison between laboratory and simulation results at 5 cc/min and each different overburden pressure.............................35... .........................................................................................................87 xiii FIGURE Pa ge 5.28 Sample scans taken along the length of the core with 500 psi overburden pressure...

Muralidharan, Vivek

2004-11-15T23:59:59.000Z

396

Annual Simulated and Observed Flow Volumes for Guadalupe  

E-Print Network [OSTI]

is funded by the Regional Monitoring Program for Water Quality in San Francisco Estuary. We gratefully Segmentation In-Steam Gauges (Flow and SSC) and Model Set-up Calero Stn. San Jose Stn. Alamitos Stn. Guadalupe). Suspended sediment concentration (SSC) measurements have been taken on a 15-minute basis in Guadalupe River

397

Visualizing flow patterns in coupled geomechanical simulation using streamlines  

E-Print Network [OSTI]

the benefits and power of streamline tracing in visualizing flow patterns through work on two cases; first, a synthetic case for studying water injection in a five spot pattern and second, a SPE 9th comparative study. The research gives encouraging results...

Parihar, Prannay

2009-05-15T23:59:59.000Z

398

Direct numerical simulation of turbulent TaylorCouette flow  

E-Print Network [OSTI]

the flow is characterized by the radius ratio, ? = R1/R2, where R1 and R2 are the radii ... vortices at the critical onset Taylor number Tc (defined as the Taylor number at which ... Beyond 5 105Tc these turbulent vortices became fragmented and lost .... employ a stiffly stable velocity-correction-type scheme with a third-order...

2007-08-23T23:59:59.000Z

399

Numerical Simulations of Dynamos Generated in Spherical Couette Flows  

E-Print Network [OSTI]

at generating a self-sustained magnetic field. No dynamo action occurs for axisymmetric flow while we always, Forest et al., 2002). No self-sustained magnetic fields were observed in the parameter regime where of ferromagnetic impellers, a self-sustained magnetic field has been observed in the Von K´arm´an Sodium (VKS

Boyer, Edmond

400

Large Eddy Simulations of Jet Flow Interactions Within Rod Bundles  

E-Print Network [OSTI]

The present work investigates the turbulent jet flow mixing of downward impinging jets within a staggered rod bundle based on previous experimental work. The two inlet jets had Reynold's numbers of 11,160 and 6,250 and were chosen to coincide...

Salpeter, Nathaniel O.

2010-07-14T23:59:59.000Z

Note: This page contains sample records for the topic "fluid flow simulation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Investigation of wellbore cooling by circulation and fluid penetration into the formation using a wellbore thermal simulator computer code  

SciTech Connect (OSTI)

The high temperatures of geothermal wells present severe problems for drilling, logging, and developing these reservoirs. Cooling the wellbore is perhaps the most common method to solve these problems. However, it is usually not clear what may be the most effective wellbore cooling mechanism for a given well. In this paper, wellbore cooling by the use of circulation or by fluid injection into the surrounding rock is investigated using a wellbore thermal simulator computer code. Short circulation times offer no prolonged cooling of fluid in the wellbore, but long circulation times (greater than ten or twenty days) greatly reduce the warming rate after shut-in. The dependence of the warming rate on the penetration distance of cooler temperatures into the rock formation (as by fluid injection) is investigated. Penetration distances of greater than 0.6 m appear to offer a substantial reduction in the warming rate. Several plots are shown which demonstrate these effects. 16 refs., 6 figs.

Duda, L.E.

1985-01-01T23:59:59.000Z

402

Development of an equivalent homogenous fluid model for pseudo-two-phase (air plus water) flow through fractured rock  

SciTech Connect (OSTI)

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

2005-07-01T23:59:59.000Z

403

Fluid--Structure Interaction : : Physiologic Simulation of Pulsatile Ventricular Assist Devices using Isogeometric Analysis  

E-Print Network [OSTI]

for prebending of wind turbine blades. 89:323336, 2012. [wind turbine rotors at full scale. Part II: Fluid structure interaction modeling with composite blades.

Long, Christopher Curtis

2013-01-01T23:59:59.000Z

404

Mechanistic Foam Flow Simulation in Heterogeneous and Multidimensional Porous Media  

E-Print Network [OSTI]

-scale simulation is a vital component of the engineering and economic evaluation of any enhanced oil recovery (EOR Copyright 1997, Society of Petroleum Engineers, Inc. Received for review, April 24, 1997 Revised, July 23 generation, and foam propagation in rock formations. Efficient application and evaluation of candidates

Patzek, Tadeusz W.

405

The effect of various mixers on the viscosity and flow properties of an oil well drilling fluid  

E-Print Network [OSTI]

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

1957-01-01T23:59:59.000Z

406

A Beale-Kato-Majda breakdown criterion for an Oldroyd-B fluid in the creeping flow regime  

E-Print Network [OSTI]

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

2007-09-10T23:59:59.000Z

407

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  

E-Print Network [OSTI]

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

408

A low diffusive Lagrange-remap scheme for the simulation of violent air-water free-surface flows.  

E-Print Network [OSTI]

. The evolution of the interfaces between phases and the consecutive complex dynamics need to be simulatedA low diffusive Lagrange-remap scheme for the simulation of violent air-water free-surface flows. Introduction Simulation of free surface flows knows an increasing interest as an essential predictive tool

Boyer, Edmond

409

Description of interfaces of fluid-tethered chains: advances in density functional theories and off-lattice computer simulations  

E-Print Network [OSTI]

Many objects of nanoscopic dimensions involve fluid-tethered chain interfaces. These systems are of interest for basic science and for several applications, in particular for design of nanodevices for specific purposes. We review recent developments of theoretical methods in this area of research and in particular of density functional (DF) approaches, which provide important insights into microscopic properties of such interfaces. The theories permit to describe the dependence of adsorption, wettability, solvation forces and electric interfacial phenomena on thermodynamic states and on characteristics of tethered chains. Computer simulations for the problems in question are overviewed as well. Theoretical results are discussed in relation to simulation results and to some experimental observations.

S. Soko?owski; J. Ilnytskyi; O. Pizio

2014-03-06T23:59:59.000Z

410

Continued development of a semianalytical solution for two-phase fluid and heat flow in a porous medium  

SciTech Connect (OSTI)

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)

1991-06-01T23:59:59.000Z

411

Use of Geophysical Techniques to Characterize Fluid Flow in a Geothermal Reservoir  

Broader source: Energy.gov [DOE]

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.

412

Simulation of heavy oil reservoir performance using a non-Newtonian flow model  

E-Print Network [OSTI]

. This reduction of viscosity as a function of shear rate has a significant effect on rates and other parameters when simulating reservoir performance. The objective of this study is to compare the simulation results of Newtonian and non-Newtonian oils under...)ected to increasing shear rate, the viscosity decreases. This behavior implies that the oil viscosity varies as a function of not only pressure, but also shear rate. This behavior is important when simulating heavy-oil reservoir performance. To simulate the flow...

Narahara, Gene Masao

1983-01-01T23:59:59.000Z

413

NMR imaging techniques and applications in the flow behavior of fluids in porous media  

E-Print Network [OSTI]

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

1990-01-01T23:59:59.000Z

414

Butz, T. and von Stryk, O.: Modelling and Simulation of ER and MR Fluid Dampers 1 ZAMM Z. angew. Math. Mech. 78 (1998) 0, 122  

E-Print Network [OSTI]

Butz, T. and von Stryk, O.: Modelling and Simulation of ER and MR Fluid Dampers 1 ZAMM · Z. angew. Math. Mech. 78 (1998) 0, 1­22 Butz, T.; von Stryk, O. Modelling and Simulation of Electro, phenomenological models, numerical simulation, pas- sive suspension MSC (1991): 65C20, 76A05 1 Introduction Electro

Stryk, Oskar von

415

Interpreting Velocities from Heat-Based Flow Sensors by NumericalSimulation  

SciTech Connect (OSTI)

We have carried out numerical simulations of three-dimensional non-isothermal flow around an in situ heat-based flow sensor to investigate how formation heterogeneities can affect the interpretation of ground water flow velocities from this instrument. The flow sensor operates by constant heating of a 0.75 m long, 5 cm diameter cylindrical probe, which contains 30 thermistors in contact with the formation. The temperature evolution at each thermistor can be inverted to obtain an estimate of the ground water flow velocity vector using the standard interpretive method, which assumes that the formation is homogeneous. Analysis of data from heat-based flow sensors installed in a sand aquifer at the Former Fort Ord Army Base near Monterey, California suggested an unexpected component of downward flow. The magnitudes of the vertical velocities were expected to be much less than the horizontal velocities at this site because the sensors were installed just above a clay aquitard. Numerical simulations were conducted to examine how differences in thermal conductivities may lead to spurious indications of vertical flow velocities. We found that a decrease in the thermal conductivity near the bottom of the sensor can perturb the temperature profiles along the instrument in such a manner that analyses assuming homogeneous thermal conductivity could indicate a vertical flow component even though flow is actually horizontal. This work demonstrates how modeling can be used to simulate instrument response to formation heterogeneity, and shows that caution must be used in interpreting data from such devices using overly simplistic assumptions.

Su, Grace W.; Freifeld, Barry M.; Oldenburg, Curtis M.; Jordan,Preston D.; Daley, Paul F.

2005-06-13T23:59:59.000Z

416

Simulation of three-dimensional shear flow around a nozzle-afterbody at high speeds  

SciTech Connect (OSTI)

In this paper, turbulent shear flows at supersonic and hypersonic speeds around a nozzle-afterbody are simulated. The three-dimensional, Reynolds-averaged Navier-Stokes equations are solved by a finite-volume and implicit method. The convective and the pressure terms are differenced by an upwind-biased algorithm. The effect of turbulence is incorporated by a modified Baldwin-Lomax eddy viscosity model. The success of the standard Baldwin-Lomax model for this flow type is shown by comparing it to a laminar case. These modifications made to the model are also shown to improve flow prediction when compared to the standard Baldwin-Lomax model. These modifications to the model reflect the effects of high compressibility, multiple walls, vortices near walls, and turbulent memory effects in the shear layer. This numerically simulated complex flowfield includes a supersonic duct flow, a hypersonic flow over an external double corner, a flow through a non-axisymmetric, internal-external nozzle, and a three-dimensional shear layer. The specific application is for the flow around the nozzle-afterbody of a generic hypersonic vehicle powered by a scramjet engine. The computed pressure distributions compared favorably with the experimentally obtained surface and off-surface flow surveys.

Baysal, O.; Hoffman, W.B. (Mechanical Engineering and Mechanics Dept., Old Dominion Univ., Norfolk, VA (United States))

1992-06-01T23:59:59.000Z

417

Flame-wall interaction simulation in a turbulent channel flow  

SciTech Connect (OSTI)

The interaction between turbulent premixed flames and channel walls is studied. Combustion is represented by a simple irreversible reaction with a large activation temperature. A low heat release assumption is used, but feedback to the flowfield can be allowed through viscosity changes. The effect of wall distance on local and global flame structure is investigated. Quenching distances and maximum wall heat fluxed computed in laminar cases are compared to DNS results. It is found that quenching distances decrease and maximum heat fluxes increase relative to laminar flame values, scaling with the turbulent strain rate. It is shown that these effects are due to large coherent structures which push flame elements towards the wall. The effect of wall strain in flame-wall interaction is studied in a stagnation line flow; this is used to explain the DNS results. The effects of the flame on the flow through viscosity changes is studied. It is also shown that remarkable flame events are produced by flame interaction with a horseshoe vortex: burned gases are pushed towards the wall at high speed and induce quenching and high wall heat flux while fresh gases are expelled from the wall region and form finger-like structures. Effects of the wall on flame surface density are investigated.

Bruneaux, G.; Akselvoll, K.; Poinsot, T.; Ferziger, J.H.

1996-10-01T23:59:59.000Z

418

Vortical Inviscid Flows with Two-Way Solid-Fluid Coupling  

E-Print Network [OSTI]

, 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

419

MATHEMATICAL MODELING OF THREE-DIMENSIONAL DIE FLOWS OF VISCOPLASTIC FLUIDS WITH WALL SLIP  

E-Print Network [OSTI]

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

420

A Well-Balanced Scheme For Two-Fluid Flows In Variable Cross-Section ducts  

E-Print Network [OSTI]

, ) 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

Paris-Sud XI, Université de

Note: This page contains sample records for the topic "fluid flow simulation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Study of Laminar Flow Forced Convection Heat Transfer Behavior of a Phase Change Material Fluid  

E-Print Network [OSTI]

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

2010-01-14T23:59:59.000Z

422

Fusion Engineering and Design 82 (2007) 22172225 Integrated thermo-fluid analysis towards helium flow  

E-Print Network [OSTI]

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

Abdou, Mohamed

423

LETTER TO THE EDITOR AC Electric-Field-Induced Fluid Flow in Microelectrodes  

E-Print Network [OSTI]

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

424

Numerical simulation of two-phase flow in discrete fractures using Rayleigh-Ritz finite element method  

E-Print Network [OSTI]

Spontaneous imbibition plays a very important role in the displacement mechanism of non-wetting fluid in naturally fractured reservoirs. We developed a new 2D two-phase finite element numerical model, as available commercial simulators cannot...

Kaul, Sandeep P.

2004-09-30T23:59:59.000Z

425

Simulation analysis of within-day flow fluctuation effects on trout below flaming Gorge Dam.  

SciTech Connect (OSTI)

In addition to being renewable, hydropower has the advantage of allowing rapid load-following, in that the generation rate can easily be varied within a day to match the demand for power. However, the flow fluctuations that result from load-following can be controversial, in part because they may affect downstream fish populations. At Flaming Gorge Dam, located on the Green River in northeastern Utah, concern has been raised about whether flow fluctuations caused by the dam disrupt feeding at a tailwater trout fishery, as fish move in response to flow changes and as the flow changes alter the amount or timing of the invertebrate drift that trout feed on. Western Area Power Administration (Western), which controls power production on submonthly time scales, has made several operational changes to address concerns about flow fluctuation effects on fisheries. These changes include reducing the number of daily flow peaks from two to one and operating within a restricted range of flows. These changes significantly reduce the value of the power produced at Flaming Gorge Dam and put higher load-following pressure on other power plants. Consequently, Western has great interest in understanding what benefits these restrictions provide to the fishery and whether adjusting the restrictions could provide a better tradeoff between power and non-power concerns. Directly evaluating the effects of flow fluctuations on fish populations is unfortunately difficult. Effects are expected to be relatively small, so tightly controlled experiments with large sample sizes and long study durations would be needed to evaluate them. Such experiments would be extremely expensive and would be subject to the confounding effects of uncontrollable variations in factors such as runoff and weather. Computer simulation using individual-based models (IBMs) is an alternative study approach for ecological problems that are not amenable to analysis using field studies alone. An IBM simulates how a population responds to environmental changes by representing how the population's individuals interact with their environment and each other. IBMs represent key characteristics of both individual organisms (trout, in this case) and the environment, thus allowing controlled simulation experiments to analyze the effects of changes in the key variables. For the flow fluctuation problem at Flaming Gorge Dam, the key environmental variables are flow rates and invertebrate drift concentrations, and the most important processes involve how trout adapt to changes (over space and time) in growth potential and mortality risk. This report documents simulation analyses of flow fluctuation effects on trout populations. The analyses were conducted in a highly controlled fashion: an IBM was used to predict production (survival and growth) of trout populations under a variety of scenarios that differ only in the level or type of flow fluctuation.

Railsback, S. F.; Hayse, J. W.; LaGory, K. E.; Environmental Science Division; EPRI

2006-01-01T23:59:59.000Z

426

Measurement of two-phase flow at the core upper plenum interface under simulated reflood conditions  

SciTech Connect (OSTI)

Objectives of the Instrument Development Loop program were to simulate flows at the core/upper plenum interface during the reflood phase of a LOCA and to develop instruments for measuring mass-flows at this interface. A tie plate drag body was developed and tested successfully, and the data obtained were shown to be equivalent to pressure drops. The tie-plate drag body gave useful measurements in pure downflow, and the drag/turbine combination correlates with mass flow for high upflow. (DLC)

Thomas, D.G.; Combs, S.K.; Bagwell, M.E.

1980-01-01T23:59:59.000Z

427

Accurate direct Eulerian simulation of dynamic elastic-plastic flow  

SciTech Connect (OSTI)

The simulation of dynamic, large strain deformation is an important, difficult, and unsolved computational challenge. Existing Eulerian schemes for dynamic material response are plagued by unresolved issues. We present a new scheme for the first-order system of elasto-plasticity equations in the Eulerian frame. This system has an intrinsic constraint on the inverse deformation gradient. Standard Godunov schemes do not satisfy this constraint. The method of Flux Distributions (FD) was devised to discretely enforce such constraints for numerical schemes with cell-centered variables. We describe a Flux Distribution approach that enforces the inverse deformation gradient constraint. As this approach is new and novel, we do not yet have numerical results to validate our claims. This paper is the first installment of our program to develop this new method.

Kamm, James R [Los Alamos National Laboratory; Walter, John W [Los Alamos National Laboratory

2009-01-01T23:59:59.000Z

428

Plasma flow measurements in a simulated low earth orbit plasma  

SciTech Connect (OSTI)

The employment of large, higher power solar arrays for space operation has been considered, taking into account a utilization of high operating voltages. In connection with the consideration of such arrays, attention must be given to the fact that the ambient environment of space contains a tenuous low energy plasma which can interact with the high voltage array causing power 'leakage' and arcing. An investigation has been conducted with the aim to simulate the behavior of such an array in low-earth-orbit (LEO). During the experiments, local concentrations of the 'leakage' current were observed when the panel was at a high voltage. These concentrations could overload or damage a small area of cells in a large string. It was hypothesized that this effect was produced by electrostatic focusing of the particles by the sheath fields. To verify this experimentally, an end-effect Langmuir probe was employed. The obtained results are discussed.

Gabriel, S.B. (California Institute of Technology, Jet Propulsion Laboratory, Electrical Power and Propulsion Section, Pasadena, CA); Mccoy, J.E. (NASA, Johnson Space Center, Houston, TX); Carruth, M.R. Jr. (NASA, Marshall Space Flight Center, Huntsville, AL)

1982-01-01T23:59:59.000Z

429

Coupling of a multizone airflow simulation program with computational fluid dynamics for indoor environmental analysis  

E-Print Network [OSTI]

Current design of building indoor environment comprises macroscopIC approaches, such as CONT AM multizone airflow analysis tool, and microscopic approaches that apply Computational Fluid Dynamics (CFD). Each has certain ...

Gao, Yang, 1974-

2002-01-01T23:59:59.000Z

430

On the Fundamental Unsteady Fluid Dynamics of Shock-Induced Flows through Ducts  

E-Print Network [OSTI]

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

2013-04-29T23:59:59.000Z

431

Review of fluid flow and convective heat transfer within rotating disk cavities  

E-Print Network [OSTI]

-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

Boyer, Edmond

432

Fluid Flow In The Resurgent Dome Of Long Valley Caldera- Implications...  

Open Energy Info (EERE)

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,...

433

Under consideration for publication in J. Fluid Mech. 1 Nonlinear free surface flows past a semi-  

E-Print Network [OSTI]

- 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

434

The role of homology in fluid vortices I: non-relativistic flow  

E-Print Network [OSTI]

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

2014-12-09T23:59:59.000Z

435

Fluid simulation of an electrostatic plasma sheath with two species of positive ions and charged nanoparticles  

SciTech Connect (OSTI)

One-dimensional fluid simulations are used to study the dynamics of an electrostatic plasma sheath containing nanosized dust grains and two species of positive ions, i.e., He{sup +} and Ar{sup +}. The impacts of the concentration of each species, the velocity at the sheath edge of the ions, and the bias voltage of the substrate, on the spatial distribution of the velocity and number density of the plasma particles, and the incident fluxes of the ions on the substrate, are investigated. The numerical results show that the sheath thickness increases with increasing {sigma}, the density ratio of He{sup +} ions to Ar{sup +} ions at the sheath edge. For nanosized dust particles considered in this work, the dominant forces are the ion drag and the electric force and the effects of the neutral drag and gravity are negligible. Due to enhancement of the ion drag force and the electric force, the dust velocity increases and, consequently, the dust number density decreases as the concentration at the sheath edge of Ar{sup +} ions is increased. For the same velocity and number density at the sheath edge, the number density of Ar{sup +} ions near the wall is larger than that of He{sup +} ions, but their incident fluxes are the same. The maximum in the dust number density increases with the velocity of Ar{sup +} ions at the sheath edge, but it weakly changes with the Mach number of He{sup +} ions, except for large values of {sigma}. The position of the maximum dust number density initially decreases very quickly with increasing the velocity at the sheath edge of the ions from small values, but then at larger values it changes quite slowly. The differences in the sheath parameters for different values of {sigma} disappear at some values of the velocity at the sheath edge of the ions and dust particles. The incident flux of the ions are independent of the bias voltage of the substrate, but their kinetic energy is equal to the bias potential.

Foroutan, G. [Department of Physics, Faculty of Science, Sahand University of Technology, 51335-1996 Tabriz (Iran, Islamic Republic of); Nanostructure Material Research Center, Sahand University of Technology, 51335-1996 Tabriz (Iran, Islamic Republic of) and School of Physics, University of Sydney, New South Wales 2006, Sydney (Australia)

2010-12-15T23:59:59.000Z

436

Elevated thermal maturation in Pennsylvanian rocks, Cherokee basin, southeastern Kansas: Importance of regional fluid flow  

SciTech Connect (OSTI)

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))

1991-03-01T23:59:59.000Z

437

Multiparticle imaging technique for two-phase fluid flows using pulsed laser speckle velocimetry. Final report, September 1988--November 1992  

SciTech Connect (OSTI)

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.

1992-12-01T23:59:59.000Z

438

Fluid dynamic studies for a simulated Melton Valley Storage Tank slurry  

SciTech Connect (OSTI)

The Melton Valley Storage Tanks (MVSTs), are used for the collection and storage of remote-handled radioactive liquid wastes. These wastes, which were typically acidic when generated, were neutralized with the addition of sodium hydroxide to protect the storage tanks from corrosion, but this caused the transuranic and heavy metals to precipitate. These wastes will eventually need to be removed from the tanks for ultimate disposal. The objective of the research activities discussed in this report is to support the design of a pipeline transport system between the MVSTs and a treatment facility. Since the wastes in the MVSTs are highly radioactive, a surrogate slurry was developed for this study. Rheological properties of the simulated slurry were determined in a test loop in which the slurry was circulated through three pipeline viscometers of different diameters. Pressure drop data at varying flow rates were used to obtain shear stress and shear rate data. The data were analyzed, and the slurry rheological properties were analyzed by the Power Law model and the Bingham plastic model. The plastic viscosity and yield stress data obtained from the rheological tests were used as inputs for a piping design software package, and the pressure drops predicted by the software compared well with the pressure drop data obtained from the test loop. The minimum transport velocity was determine for the slurry by adding known nominal sizes of glass spheres to the slurry. However, it was shown that the surrogate slurry exhibited hindered settling, which may substantially decrease the minimum transport velocity. Therefore, it may be desired to perform additional tests with a surrogate with a lower concentration of suspended solids to determine the minimum transport velocity.

Hylton, T.D.; Youngblood, E.L.; Cummins, R.L.

1994-07-01T23:59:59.000Z

439

Investigation of wellbore cooling by circulation and fluid penetration into the formation using a wellbore thermal simulator computer code  

SciTech Connect (OSTI)

The high temperatures of geothermal wells present severe problems for drilling, logging, and developing these reservoirs. Cooling the wellbore is perhaps the most common method to solve these problems. However, it is usually not clear what may be the most effective wellbore cooling mechanism for a given well. In this paper, wellbore cooling by the use of circulation or by fluid injection into the surrounding rock is investigated using a wellbore thermal simulator computer code. Short circulation times offer no prolonged cooling of the wellbore, but long circulation times (greater than ten or twenty days) greatly reduce the warming rate after shut-in. The dependence of the warming rate on the penetration distance of cooler temperatures into the rock formation (as by fluid injection) is investigated. Penetration distances of greater than 0.6 m appear to offer a substantial reduction in the warming rate. Several plots are shown which demonstrate these effects.

Duda, L.E.

1987-01-01T23:59:59.000Z

440

Multidimensional Simulation of Plasma in Argon through a Shock in Hypersonic Flow  

E-Print Network [OSTI]

Multidimensional Simulation of Plasma in Argon through a Shock in Hypersonic Flow Amrita K. Lonkar in gases at hypersonic speeds. A plasma is composed of multiple species in thermo-chemical nonequlibrium major advancements in the field of hypersonics in the past quarter century. Rocket- powered launch

Alonso, Juan J.

Note: This page contains sample records for the topic "fluid flow simulation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Multidimensional Simulation of Plasma in Argon through a Shock in Hypersonic Flow  

E-Print Network [OSTI]

Multidimensional Simulation of Plasma in Argon through a Shock in Hypersonic Flow Amrita K. Lonkar in gases at hypersonic speeds. A plasma is composed of multiple species in thermo-chemical nonequlibrium of hypersonics in the past quarter century. Rocket- powered launch vehicles typically achieve hypersonic speeds

Alonso, Juan J.

442

Extracting the Acoustic pressure field from Large Eddy Simulation of confined reactive flows  

E-Print Network [OSTI]

and non-premixed open flames3,4 as well as in more complex cases such as gas turbine combustors must be large enough to include the sources of noise as well as part of the acoustic near field.6 VeryExtracting the Acoustic pressure field from Large Eddy Simulation of confined reactive flows Camilo

Nicoud, Franck

443

MULTIPHASE FLOW SIMULATION WITH VARIOUS BOUNDARY CONDITIONS Z. CHEN, R. E. EWING, and M. ESPEDAL  

E-Print Network [OSTI]

commonly used boundary conditions for groundwater hydrology and petroleum engineering problems can­ water hydrology and petroleum engineering is considered. The phase flow equations are given be incorporated into the pressure­saturation formu­ lation. INTRODUCTION In petroleum reservoir simulation

Ewing, Richard E.

444

Flow Simulations of a Rotating MidSized Rim Driven Wind Turbine  

E-Print Network [OSTI]

Flow Simulations of a Rotating MidSized Rim Driven Wind Turbine Bryan E. Kaiser1 , Andrew B: poroseva@unm.edu Introduction Conventional horizontal axis wind turbines (HAWTs) require harvesting. To overcome this limitation, small to midsized wind turbine designs capable of power

Maccabe, Barney

445

Simulation of water flow and solute transport in free-drainage lysimeters and field soils with  

E-Print Network [OSTI]

Simulation of water flow and solute transport in free-drainage lysimeters and field soils for studying the fate and transport of chemicals in soil. Large-scale field lysimeters are used to assess pesticide behaviour and radionuclide transport, and are assumed to represent natural field conditions better

Flury, Markus

446

Large Eddy Simulation Analysis of Flow Field Inside a High-g Combustor  

E-Print Network [OSTI]

Large Eddy Simulation Analysis of Flow Field Inside a High-g Combustor C. Heye , C. Lietz , J-compact combustors (UCC) are a technology for reducing the size of combustors. In these combustors the fuel and air results exhibit significant entrainment of fuel into recirculation zones inside the combustor, however

Raman, Venkat

447

A Coupled Approach for Plasma-Based Flow Control Simulations of Wing Sections  

E-Print Network [OSTI]

a role in momentum coupling, though as noted in Ref. 10 there is no significant heating of the airA Coupled Approach for Plasma-Based Flow Control Simulations of Wing Sections Datta V. Gaitonde Vehicles Directorate Kettering University Air Force Research Laboratory Flint, MI 48504 Wright

Roy, Subrata

448

Society of Petroleum Engineers Staggered In Time Coupling of Reservoir Flow Simulation and Geomechanical Defor-  

E-Print Network [OSTI]

Society of Petroleum Engineers SPE 51920 Staggered In Time Coupling of Reservoir Flow Simulation, The University of Texas at Austin Copyright 1999, Society of Petroleum Engineers, Inc. Thispaperwas by the Society of Petroleum Engineers and are subject to correction by the author(s). The material, as presented

Minkoff, Susan E.

449

Numerical simulations of gas-particle flows with combustion Julien NUSSBAUM  

E-Print Network [OSTI]

Numerical simulations of gas-particle flows with combustion Julien NUSSBAUM French-german Research. At the initial time, the mixture of gas-powder grains is contained in the combustion chamber, limited gas species. The pressure increases in the combustion chamber, while the front flame propagates

Paris-Sud XI, Université de

450

Cosmological MHD simulation of a cooling flow cluster  

E-Print Network [OSTI]

Various observations of magnetic fields in the Intra-Cluster Medium (ICM), most of the time restricted to cluster cores, point towards field strength of the order of a few microG (synchrotron radiation from radio relics and radio halos, inverse Compton radiation in X-rays and Faraday rotation measure of polarised background sources). Both the origin and the spatial structure of galaxy clusters magnetic fields are still under debate. In particular, the radial profile of the magnetic field, from the core of clusters to their outskirts, is of great importance for cosmic rays propagation within the Cosmic Web. In this letter, we highlight the importance of cooling processes in amplifying the magnetic field in the core of galaxy clusters up to one order of magnitude above the typical amplification obtained for a pure adiabatic evolution. We have performed a "zoom'' cosmological simulation of a 3 keV cluster, including dark matter and gas dynamics, atomic cooling, UV heating and star formation using the newly developed MHD solver in the AMR code RAMSES. Magnetic field amplification proceeds mainly through gravitational contraction. Shearing motions due to turbulence provide additional amplification in the outskirts of the cluster, while magnetic reconnection during mergers causes magnetic field dissipation in the core. Cooling processes have a strong impact on the magnetic field structure in the cluster. First, due to the sharp rise of the gas density in the centre, gravitational amplification is significantly amplified, when compared to the non--radiative run. Second, due to cooling processes, shearing motions are much stronger in the core than in the adiabatic case, leading to additional field amplification and no significant magnetic reconnection.

Y. Dubois; R. Teyssier

2008-03-31T23:59:59.000Z

451

Computational fluid dynamic applications  

SciTech Connect (OSTI)

The rapid advancement of computational capability including speed and memory size has prompted the wide use of computational fluid dynamics (CFD) codes to simulate complex flow systems. CFD simulations are used to study the operating problems encountered in system, to evaluate the impacts of operation/design parameters on the performance of a system, and to investigate novel design concepts. CFD codes are generally developed based on the conservation laws of mass, momentum, and energy that govern the characteristics of a flow. The governing equations are simplified and discretized for a selected computational grid system. Numerical methods are selected to simplify and calculate approximate flow properties. For turbulent, reacting, and multiphase flow systems the complex processes relating to these aspects of the flow, i.e., turbulent diffusion, combustion kinetics, interfacial drag and heat and mass transfer, etc., are described in mathematical models, based on a combination of fundamental physics and empirical data, that are incorporated into the code. CFD simulation has been applied to a large variety of practical and industrial scale flow systems.

Chang, S.-L.; Lottes, S. A.; Zhou, C. Q.

2000-04-03T23:59:59.000Z

452

Perturbative analysis of sheared flow Kelvin-Helmholtz instability in a weakly relativistic magnetized electron fluid  

SciTech Connect (OSTI)

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)

2012-05-15T23:59:59.000Z

453

Two-fluid flowing equilibria of compact plasmas Loren C. Steinhauer  

E-Print Network [OSTI]

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

454

Transient fluid and heat flow modeling in coupled wellbore/reservoir systems  

E-Print Network [OSTI]

....................................................... 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

2009-05-15T23:59:59.000Z

455

Slip Flow Fluid-Structure-Interaction J. van Rij, T. Harman, T. Ameel*  

E-Print Network [OSTI]

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

456

Imaging Fluid Flow in Geothermal Wells Using Distributed Thermal Perturbation Sensing  

Broader source: Energy.gov [DOE]

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.

457

Different approximations of shallow fluid flow over an obstacle B. T. Nadiga and L. G. Margolin  

E-Print Network [OSTI]

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"

458

Fluid flow near reservoir lakes inferred from the spatial and temporal analysis of the electric potential  

E-Print Network [OSTI]

, 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

459

Characterizing fractured rock for fluid-flow, geomechanical, and paleostress modeling: Methods and preliminary results from Yucca Mountain, Nevada  

SciTech Connect (OSTI)

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.

1993-12-31T23:59:59.000Z

460

The topological susceptibility from grand canonical simulations in the interacting instanton liquid model: strongly associating fluids and biased Monte Carlo  

E-Print Network [OSTI]

This is the second in a series of papers that investigates the topological susceptibility in the interacting instanton liquid model (IILM) at finite temperature, and deals with the technical issues relating to the Monte Carlo simulations. The IILM reduces field theory to a molecular dynamics description, and for `physical' quark masses the system behaves like a strongly associating fluid. We will argue that this is a generic feature for very light Dirac quark in a non-trivial background, described in the semi-classical approach. To get rid of unnecessary complications, we will present the ideas of biased Monte Carlo, and implement the transition probabilities, for a toy model.

Olivier Wantz

2010-01-14T23:59:59.000Z

Note: This page contains sample records for the topic "fluid flow simulation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

Viscoelastic fluid flow in a 2D channel bounded above by a deformable finite thickness elastic wall  

E-Print Network [OSTI]

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

2015-01-01T23:59:59.000Z

462

A next-generation modeling capability assesses wind turbine array fluid dynamics and aeroelastic simulations  

E-Print Network [OSTI]

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

463

Global Stability Analysis of Fluid Flows using Sum-of-Squares  

E-Print Network [OSTI]

Jul 1, 2011 ... The first of these is the classical energy approach of [5, 16], which provides conservative ..... Standard software tools are freely available for posing and solving ... stability limit estimated by direct numerical simulation. ...... make assumptions identical to those in [9, 10] for the purposes of comparison.

2011-07-01T23:59:59.000Z

464

Fluid Flow and Thermodynamic Analysis of a Wing Anti-Icing System  

E-Print Network [OSTI]

is installed on most passenger airplanes. It introduces hot bleeding air from the power plant into the wing-mail: liu@utias.utoronto.ca Received 26 August 2003. 1. INTRODUCTION The thermal anti-icing system of this paper is to apply the existing CFD tools to assist the system modeling and simulation analysis

Liu, Hugh H.T.

465

Numerical simulations of aggregate breakup in bounded and unbounded turbulent flows  

E-Print Network [OSTI]

Breakup of small aggregates in fully developed turbulence is studied by means of direct numerical simulations in a series of typical bounded and unbounded flow configurations, such as a turbulent channel flow, a developing boundary layer and homogeneous isotropic turbulence. The simplest criterion for breakup is adopted, whereas aggregate breakup occurs when the local hydrodynamic stress $\\sigma\\sim \\varepsilon^{1/2}$, with $\\varepsilon$ being the energy dissipation at the position of the aggregate, overcomes a given threshold $\\sigma_\\mathrm{cr}$, which is characteristic for a given type of aggregates. Results show that the breakup rate decreases with increasing threshold. For small thresholds, it develops a universal scaling among the different flows. For high thresholds, the breakup rates show strong differences between the different flow configurations, highlighting the importance of non-universal mean-flow properties. To further assess the effects of flow inhomogeneity and turbulent fluctuations, theresults are compared with those obtained in a smooth stochastic flow. Furthermore, we discuss the limitations and applicability of a set of independent proxies.

Matthaus U. Babler; Luca Biferale; Luca Brandt; Ulrike Feudel; Ksenia Guseva; Alessandra S. Lanotte; Cristian Marchioli; Francesco Picano; Gaetano Sardina; Alfredo Soldati; Federico Toschi

2015-02-17T23:59:59.000Z

466

Identification of fluid-flow paths in the Cerro Prieto geothermal field  

SciTech Connect (OSTI)

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.

1982-05-01T23:59:59.000Z

467

Numerical Simulation of the Flow of a Power Law Fluid in an Elbow Bend  

E-Print Network [OSTI]

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

2010-07-14T23:59:59.000Z

468

Modeling electrospinning process and a numerical scheme using Lattice Boltzmann method to simulate viscoelastic fluid flows  

E-Print Network [OSTI]

of secondary electric field on electrospinning process and whipping instability. It is observed that the external secondary field unwinds the jet spirals, reduces the whipping instability and increases the tension in the fiber. Lattice Boltzmann method (LBM...

Karra, Satish

2009-05-15T23:59:59.000Z

469

A computational model for viscous fluid flow, heat transfer, and melting in in situ vitrification melt pools  

SciTech Connect (OSTI)

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.

1991-11-01T23:59:59.000Z

470

Self-consistent fluid modeling and simulation on a pulsed microwave atmospheric-pressure argon plasma jet  

SciTech Connect (OSTI)

In present study, a pulsed lower-power microwave-driven atmospheric-pressure argon plasma jet has been introduced with the type of coaxial transmission line resonator. The plasma jet plume is with room air temperature, even can be directly touched by human body without any hot harm. In order to study ionization process of the proposed plasma jet, a self-consistent hybrid fluid model is constructed in which Maxwell's equations are solved numerically by finite-difference time-domain method and a fluid model is used to study the characteristics of argon plasma evolution. With a Guass type input power function, the spatio-temporal distributions of the electron density, the electron temperature, the electric field, and the absorbed power density have been simulated, respectively. The simulation results suggest that the peak values of the electron temperature and the electric field are synchronous with the input pulsed microwave power but the maximum quantities of the electron density and the absorbed power density are lagged to the microwave power excitation. In addition, the pulsed plasma jet excited by the local enhanced electric field of surface plasmon polaritons should be the discharge mechanism of the proposed plasma jet.

Chen, Zhaoquan, E-mail: zqchen@aust.edu.cn [Faculty of Physics, St. Petersburg State University, St. Petersburg 198504 (Russian Federation); College of Electrical and Information Engineering, Anhui University of Science and Technology, Huainan, Anhui 232001 (China); Yin, Zhixiang, E-mail: zxyin66@163.com; Chen, Minggong; Hong, Lingli; Hu, Yelin; Huang, Yourui [College of Electrical and Information Engineering, Anhui University of Science and Technology, Huainan, Anhui 232001 (China); Xia, Guangqing; Liu, Minghai [State Key Laboratory of Advanced Electromagnetic Engineering and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China); Kudryavtsev, A. A. [Faculty of Physics, St. Petersburg State University, St. Petersburg 198504 (Russian Federation)

2014-10-21T23:59:59.000Z

471

Materials Science and Engineering B 117 (2005) 5361 Finite element analysis-based design of a fluid-flow control nano-valve  

E-Print Network [OSTI]

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

472

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.  

E-Print Network [OSTI]

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

Paris-Sud XI, Université de

473

CFD evaluation of pipeline gas stratification at low fluid flow due to temperature effects  

E-Print Network [OSTI]

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

2005-02-17T23:59:59.000Z

474

Identification of whistling ability of a single hole orifice from an incompressible flow simulation  

SciTech Connect (OSTI)

Pure tone noise from orifices in pipe result from vortex shedding with lock-in. Acoustic amplification at the orifice is coupled to resonant condition to create self-sustained oscillations. One key feature of this phenomenon is hence the ability of an orifice to amplify acoustic waves in a given range of frequencies. Here a numerical investigation of the linear response of an orifice is undertaken, with the support of experimental data for validation. The study deals with a sharp edge orifice. Its diameter equals to 0.015 m and its thickness to 0.005 m. The pipe diameter is 0.030 m. An air flow with a Mach number 0.026 and a Reynolds number 18000 in the main pipe is present. At such a low Mach number; the fluid behavior can reasonably be described as locally incompressible. The incompressible Unsteady Reynolds Averaged Navier-Stokes (URANS) equations are solved with the help of a finite volume fluid mechanics software. The orifice is submitted to an average flow velocity, with superimposed small harmonic perturbations. The harmonic response of the orifice is the difference between the upstream and downstream pressures, and a straightforward calculation brings out the acoustic impedance of the orifice. Comparison with experiments shows that the main physical features of the whistling phenomenon are reasonably reproduced. (authors)

Lacombe, Romain; Moussou, Pierre [LaMSID - UMR EDF/CNRS/CEA, DEN-DM2S, 8193 EDF R et D, 1 avenue du General de Gaulle, 92141 Clamart Cedex (France); Auregan, Yves [Universite du Maine, Le Mans, (France)

2012-07-01T23:59:59.000Z

475

3D SPH Simulations of Shocks in Accretion Flows around black holes  

E-Print Network [OSTI]

We present the simulation of 3D time dependent flow of rotating ideal gas falling into a Schwarzschild black hole. It is shown that also in the 3D case steady shocks are formed in a wide range of parameters (initial angular momentum and thermal energy). We therefore highlight the stability of the phenomenon of shock formation in sub keplerian flows onto black holes, and reenforce the role of the shocks in the high luminosity emission from black hole candidates. The simulations have been performed using a parallelized code based on the Smoothed Particles Hydrodynamics method (SPH). We also discuss some properties of the shock problem that allow its use as a quantitative test of the accuracy of the used numerical method. This shows that the accuracy of SPH is acceptable although not excellent.

G. Gerardi; D. Molteni; V. Teresi

2005-01-25T23:59:59.000Z

476

Flow Components in a NaK Test Loop Designed to Simulate Conditions in a Nuclear Surface Power Reactor  

SciTech Connect (OSTI)

A test loop using NaK as the working fluid is presently in use to study material compatibility effects on various components that comprise a possible nuclear reactor design for use on the lunar surface. A DC electromagnetic (EM) pump has been designed and implemented as a means of actively controlling the NaK flow rate through the system and an EM flow sensor is employed to monitor the developed flow rate. These components allow for the matching of the flow rate conditions in test loops with those that would be found in a full-scale surface-power reactor. The design and operating characteristics of the EM pump and flow sensor are presented. In the EM pump, current is applied to a set of electrodes to produce a Lorentz body force in the fluid. A measurement of the induced voltage (back-EMF) in the flow sensor provides the means of monitoring flow rate. Both components are compact, employing high magnetic field strength neodymium magnets thermally coupled to a water-cooled housing. A vacuum gap limits the heat transferred from the high temperature NaK tube to the magnets and a magnetically-permeable material completes the magnetic circuit. The pump is designed to produce a pressure rise of 34.5 kPa, and the flow sensor's predicted output is roughly 20 mV at the loop's nominal flow rate of 0.114 m{sup 3}/hr.

Polzin, Kurt A.; Godfroy, Thomas J. [NASA Marshall Space Flight Center Propulsion Research and Technology Applications Branch/ER24, MSFC, AL 35812 (United States)

2008-01-21T23:59:59.000Z

477

A numerical study of steady fluid flow in the entry region of a straight circular tube  

E-Print Network [OSTI]

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

1967-01-01T23:59:59.000Z

478

Rheological properties of soft-glassy flows from hydro-kinetic simulations  

E-Print Network [OSTI]

Based on numerical simulations of a lattice kinetic model for soft-glassy materials, we characterize the global rheology of a dense emulsion-like system, under three representative load conditions: Couette flow, time-oscillating Strain and Kolmogorov flow. It is found that in all cases the rheology is described by a Herschel-Bulkley (HB) relation, $\\sigma = {\\sigma}_{Y} + A S^{\\beta}$, with the yield stress ${\\sigma}_{Y}$ largely independent of the loading scenario. A proper rescaling of the HB parameters permits to describe heterogeneous flows with space-dependent stresses, based on the notion of cooperativity, as recently proposed to characterize the degree of non-locality of stress relaxation phenomena in soft-glassy materials.

R. Benzi; M. Bernaschi; M. Sbragaglia; S. Succi

2014-02-28T23:59:59.000Z

479

Simulated effects of climate change on the Death Valley regional ground-water flow system, Nevada and California  

SciTech Connect (OSTI)

The US Geological Survey, in cooperation with the US Department of Energy, is evaluating the geologic and hydrologic characteristics of the Death Valley regional flow system as part of the Yucca Mountain Project. As part of the hydrologic investigation, regional, three-dimensional conceptual and numerical ground-water-flow models have been developed to assess the potential effects of past and future climates on the regional flow system. A simulation that is based on climatic conditions 21,000 years ago was evaluated by comparing the simulated results to observation of paleodischarge sites. Following acceptable simulation of a past climate, a possible future ground-water-flow system, with climatic conditions that represent a doubling of atmospheric carbon dioxide, was simulated. The steady-state simulations were based on the present-day, steady-state, regional ground-water-flow model. The finite-difference model consisted of 163 rows, 153 columns, and 3 layers and was simulated using MODFLOWP. Climate changes were implemented in the regional ground-water-flow model by changing the distribution of ground-water recharge. Global-scale, average-annual, simulated precipitation for both past- and future-climate conditions developed elsewhere were resampled to the model-grid resolution. A polynomial function that represents the Maxey-Eakin method for estimating recharge from precipitation was used to develop recharge distributions for simulation.

D`Agnese, F.A.; O`Brien, G.M.; Faunt, C.C.; San Juan, C.A.

1999-04-01T23:59:59.000Z

480

Optimized Cross-Slot Flow Geometry for Microfluidic Extensional Rheometry  

E-Print Network [OSTI]

A precision-machined cross-slot flow geometry with a shape that has been optimized by numerical simulation of the fluid kinematics is fabricated and used to measure the extensional viscosity of a dilute polymer solution. ...

Haward, Simon J.

Note: This page contains sample records for the topic "fluid flow simulation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


481

Gas-Kinetic Scheme for Continuum and Near-Continuum Hypersonic Flows  

E-Print Network [OSTI]

Gas-Kinetic Scheme for Continuum and Near-Continuum Hypersonic Flows Wei Liao and Li-Shi Luo Old. The gas-kinetic schemes are validated with simulations of the hypersonic flow past a hollow flare at Mach and simulation of complex hypersonic flows become very challenging for computa- tional fluid dynamics (CFD) [1

Xu, Kun

482

Numerical simulation of swirling flow in complex hydroturbine draft tube using unsteady statistical turbulence models  

SciTech Connect (OSTI)

A numerical method is developed for carrying out unsteady Reynolds-averaged Navier-Stokes (URANS) simulations and detached-eddy simulations (DESs) in complex 3D geometries. The method is applied to simulate incompressible swirling flow in a typical hydroturbine draft tube, which consists of a strongly curved 90 degree elbow and two piers. The governing equations are solved with a second-order-accurate, finite-volume, dual-time-stepping artificial compressibility approach for a Reynolds number of 1.1 million on a mesh with 1.8 million nodes. The geometrical complexities of the draft tube are handled using domain decomposition with overset (chimera) grids. Numerical simulations show that unsteady statistical turbulence models can capture very complex 3D flow phenomena dominated by geometry-induced, large-scale instabilities and unsteady coherent structures such as the onset of vortex breakdown and the formation of the unsteady rope vortex downstream of the turbine runner. Both URANS and DES appear to yield the general shape and magnitude of mean velocity profiles in reasonable agreement with measurements. Significant discrepancies among the DES and URANS predictions of the turbulence statistics are also observed in the straight downstream diffuser.

Paik, Joongcheol [University of Minnesota; Sotiropoulos, Fotis [University of Minnesota; Sale, Michael J [ORNL

2005-06-01T23:59:59.000Z

483

3rd International symposium on fluid flow measurement effects of acoustic noise on orifice meters  

SciTech Connect (OSTI)

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)

1995-12-31T23:59:59.000Z

484

Fundamentals of Engineering (FE) Exam Fluid Mechanics Review  

E-Print Network [OSTI]

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

485

Development and verification of a numerical simulator to calculate the bottom hole flowing pressures in multiphase systems  

E-Print Network [OSTI]

the Middle East, but there were some wells located in offshore Louisiana. There was a wide range Of variation in the variables for each well, some of these were: flow rates, gas/oil ratios, total depths, tubing sizes, fluid Compositions, and water cuts...

Rasool, Syed Ahmed

1994-01-01T23:59:59.000Z

486

Three-dimensional Simulation of Magnetized Cloud Fragmentation Induced by Nonlinear Flows and Ambipolar Diffusion  

E-Print Network [OSTI]

We demonstrate that the formation of collapsing cores in subcritical clouds is accelerated by nonlinear flows, by performing three-dimensional non-ideal MHD simulations. An initial random supersonic (and trans-Alfvenic) turbulent-like flow is input into a self-gravitating gas layer that is threaded by a uniform magnetic field (perpendicular to the layer) such that the initial mass-to-flux ratio is subcritical. Magnetic ambipolar diffusion occurs very rapidly initially due to the sharp gradients introduced by the turbulent flow. It subsequently occurs more slowly in the traditional near-quasistatic manner, but in regions of greater mean density than present in the initial state. The overall timescale for runaway growth of the first core(s) is several times, 10^6 yr, even though previous studies have found a timescale of several times, 10^7 yr when starting with linear perturbations and similar physical parameters. Large-scale supersonic flows exist in the cloud and provide an observationally testable distinguishing characteristic from core formation due to linear initial perturbations. However, the nonlinear flows have decayed sufficiently that the relative infall motions onto the first core are subsonic, as in the case of starting from linear initial perturbations. The ion infall motions are very similar to those of neutrals; however, they lag the neutral infall in directions perpendicular to the mean magnetic field direction and lead the neutral infall in the direction parallel to the mean magnetic field.

Takahiro Kudoh; Shantanu Basu

2008-04-27T23:59:59.000Z

487

Rheology and microstructural evolution in pressure-driven flow of a magnetorheological fluid with strong particle-wall interactions  

E-Print Network [OSTI]

The interaction between magnetorheological (MR) fluid particles and the walls of the device that retain the field-responsive fluid is critical as this interaction provides the means for coupling the physical device to the ...

Ocalan, Murat

488

First Principles Simulations fo the Supercritical Behavior of Ore Forming Fluids  

SciTech Connect (OSTI)

Abstract of Selected Research Progress: I. First-principles simulation of solvation structure and deprotonation reactions of ore forming metal ions in very nonideal solutions: Advances in algorithms and computational performance achieved in this grant period have allowed the atomic level dynamical simulation of complex nanoscale materials using interparticle forces calculated directly from an accurate density functional solution to the electronic Schr???????????????¶dinger equation (ab-initio molecular dynamics, AIMD). Focus of this program was on the prediction and analysis of the properties of environmentally important ions in aqueous solutions. AIMD methods have provided chemical interpretations of these very complex systems with an unprecedented level of accuracy and detail. The structure of the solvation region neighboring a highly charged metal ion (e.g., 3+) in an aqueous solution is very different from that of bulk water. The many-body behaviors (polarization, charge transfer, etc.) of the ion-water and water-water interactions in this region are difficult to capture with conventional empirical potentials. However, a large numbers of waters (up to 128 waters) are required to fully describe chemical events in the extended hydrations shells and long simulation times are needed to reliably sample the system. Taken together this makes simulation at the 1st principles level a very large computational problem. Our AIMD simulation results using these methods agree with the measured octahedral structure of the 1st solvation shell of Al3+ at the 1st shell boundary and a calculated radius of 1.937???????????????? (exp. 1.9????????????????). Our calculated average 2nd shell radius agrees remarkably well with the measured radius, 4.093 ???????????????? calculated vs. the measured value of 4.0-4.15 ????????????????. Less can be experimentally determined about the structure of the 2nd shell. Our simulations show that this shell contains roughly 12 water molecules, which are trigonally coordinated to the 1st shell waters. This structure cannot be measured directly. However, the number of 2nd shell water molecules predicted by the simulation is consistent with experimental estimates. Tetrahedral bulk water coordination reappears just after the 2nd shell. Simulations with 128 waters are close to the maximum size that can effectively be performed with present day methods. While the time scale of our simulation are not long enough to observe transfers of waters from the 1st to the 2nd shell, we do see transfers occurring on a picosecond time scale between the 2nd shell and 3rd shell via an associative mechanism. This is faster than, but consistent with, the results of measurements on the more tightly bound Cr3+ system. For high temperature simulations, proton transfers occur in the solvation shells leading to transient hydrolysis species. The reaction coordinate for proton transfer involves the coordinates of neighboring solvent waters as in the Grotis mechanism for proton transfer in bulk water. Directly removing a proton from the hexaqua Al3+ ion leads to a much more labile solvation shell and to a five coordinated Al3+ ion. This is consistent with very recent rate measurements of ligand exchange and the conjugate base labilization effect. For the Al3+-H2O system results for high but subcritical temperatures are qualitatively similar to room temperature simulations. However, preliminary simulations for supercritical temperatures (750K) suggest that there may be a dramatic change in be

Weare, John H

2013-04-19T23:59:59.000Z

489

June 6, 2007 Large-Scale Scientific Computations'07, Sozopol, Bulgaria -p. 1/29 Multiscale Modeling and Simulation of Fluid  

E-Print Network [OSTI]

in porous media (soil, porous rocks, etc.) x Elasticity problems in composite materials (adobe, concrete/29 Presentation outline s Brief overview of upscaling methods in deformable porous media s The Fluid upscaling of flow in deformable porous media #12;June 6, 2007 Large-Scale Scientific Computations'07

Popov, Peter

490

Large-Scale Fluid-Structure Interaction Simulation of Viscoplastic and Fracturing  

E-Print Network [OSTI]

of large plastic deformations and rupture of thin alu- minum tubes due to the passage of ethylene-oxygen detonations. 1 Introduction The Center for Simulation of Dynamic Response of Materials at the California In with such a "weakly coupled" method, when the evolving interface geometry and velocities are imposed as boundary

Deiterding, Ralf

491

Computational Fluid Dynamics Simulation of Green Water Around a Two-dimensional Platform  

E-Print Network [OSTI]

An interface-preserving level set method is incorporated into the Reynolds-Averaged Navier-Stokes (RANS) numerical method to simulate the application of the green water phenomena around a platform and the breaking wave above the deck. In the present...

Zhao, Yucheng

2010-07-14T23:59:59.000Z

492

Self-Assembling Sup-porosity: The Effect On Fluid Flow And Seismic Wave Propagation  

SciTech Connect (OSTI)

Fractures and joints in the field often contain debris within the void spaces. Debris originates from many different mechanisms: organic and/or inorganic chemical reactions/mineralization, sediment transport, formation of a fracture, mechanical weathering or combinations of these processes. In many cases, the presence of debris forms a ??sub-porosity? within the fracture void space. This sub-porosity often is composed of material that differs from the fracture walls in mineralogy and morphology. The ??sub-porosity? may partially fill voids that are on the order of hundreds of microns and thereby reduce the local porosity to lengths scales on the order of sub-microns to tens of microns. It is quite clear that a sub-porosity affects fracture porosity, permeability and storativity. What is not known is how the existence/formation of a sub-porosity affects seismic wave propagation and consequently our ability to probe changes in the subsurface caused by the formation or alteration of a sub-porosity. If seismic techniques are to be developed to monitor the injection and containment of phases in sequestration reservoirs or the propping of hydraulically induced fracture to enhance oil & gas production, it is important to understand how a sub-porosity within a fracture affects macroscopic seismic and hydraulic measurements. A sub-porosity will directly affect the interrelationship between the seismic and hydraulic properties of a fracture. This reports contains the results of the three main topics of research that were performed (1) to determine the effect of a sub-porosity composed of spherical grains on seismic wave propagation across fractures, (2) to determine the effect of biofilm growth in pores and between grains on seismic wave propagation in sediment, and (3) to determine the effect of the scale of observation (field-of-view) on monitoring alteration the pore space within a fracture caused by reactive flow. A brief summary of the results for each topic is contained in the report and the full details of the research and approach are contained in the publications found in the Attachment section of this report. A list of presentation and publications of all work associated with this grant is also provided.

Pyrak-Nolte, Laura J. [Purdue University

2013-04-27T23:59:59.000Z

493

Numerical simulations of the Macondo well blowout reveal strong control of oil flow by reservoir permeability and exsolution of gas  

E-Print Network [OSTI]

simulation of reservoir depletion and oil flow from themodel included the oil reservoir and the well with a toppressures of the deep oil reservoir, to a two-phase oil-gas

Oldenburg, C.M.

2013-01-01T23:59:59.000Z

494

General Relativistic Hydrodynamic Simulation of Accretion Flow from a Stellar Tidal Disruption  

E-Print Network [OSTI]

We study how the matter dispersed when a supermassive black hole tidally disrupts a star joins an accretion flow. Combining a relativistic hydrodynamic simulation of the stellar disruption with a relativistic hydrodynamics simulation of the tidal debris motion, we track such a system until ~80% of the stellar mass bound to the black hole has settled into an accretion flow. Shocks near the stellar pericenter and also near the apocenter of the most tightly-bound debris dissipate orbital energy, but only enough to make the characteristic radius comparable to the semi-major axis of the most-bound material, not the tidal radius as previously thought. The outer shocks are caused by post-Newtonian effects, both on the stellar orbit during its disruption and on the tidal forces. Accumulation of mass into the accretion flow is non-monotonic and slow, requiring ~3--10x the orbital period of the most tightly-bound tidal streams, while the inflow time for most of the mass may be comparable to or longer than the mass accu...

Shiokawa, Hotaka; Cheng, Roseanne M; Piran, Tsvi; Noble, Scott C

2015-01-01T23:59:59.000Z

495

Lecture notes Introductory fluid mechanics  

E-Print Network [OSTI]

Lecture notes Introductory fluid mechanics Simon J.A. Malham Simon J.A. Malham (22nd February 2013 of fluid mechanics and along the way see lots of interesting applications. 2 Fluid flow 2.1 Flow A material essential to all modern car braking mechanisms. Fluids can be further subcatergorized. There are ideal

Malham, Simon J.A.

496

Simulation of naturally fractured reservoirs using empirical transfer function  

E-Print Network [OSTI]

This research utilizes the imbibition experiments and X-ray tomography results for modeling fluid flow in naturally fractured reservoirs. Conventional dual porosity simulation requires large number of runs to quantify transfer function parameters...

Tellapaneni, Prasanna Kumar

2004-09-30T23:59:59.000Z

497

2-D Hypersonic Non-equilibrium Flow Simulation using r-p Adaptive Time-Implicit Discontinuous Galerkin Method  

E-Print Network [OSTI]

2-D Hypersonic Non-equilibrium Flow Simulation using r-p Adaptive Time-Implicit Discontinuous Aerospace Sciences Meeting #12;1 American Institute of Aeronautics and Astronautics 2-D Hypersonic Non Galerkin (DG) methods to 2-D hypersonic