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1

Mixed finite elements for global tide models  

E-Print Network (OSTI)

We study mixed finite element methods for the linearized rotating shallow water equations with linear drag and forcing terms. By means of a strong energy estimate for an equivalent second-order formulation for the linearized momentum, we prove long-time stability of the system without energy accumulation -- the geotryptic state. A priori error estimates for the linearized momentum and free surface elevation are given in $L^2$ as well as for the time derivative and divergence of the linearized momentum. Numerical results confirm the theoretical results regarding both energy damping and convergence rates.

Cotter, Colin J

2014-01-01T23:59:59.000Z

2

Probabilistic finite element modeling of waste rollover  

SciTech Connect

Stratification of the wastes in many Hanford storage tanks has resulted in sludge layers which are capable of retaining gases formed by chemical and/or radiolytic reactions. As the gas is produced, the mechanisms of gas storage evolve until the resulting buoyancy in the sludge leads to instability, at which point the sludge ``rolls over`` and a significant volume of gas is suddenly released. Because the releases may contain flammable gases, these episodes of release are potentially hazardous. Mitigation techniques are desirable for more controlled releases at more frequent intervals. To aid the mitigation efforts, a methodology for predicting of sludge rollover at specific times is desired. This methodology would then provide a rational basis for the development of a schedule for the mitigation procedures. In addition, a knowledge of the sensitivity of the sludge rollovers to various physical and chemical properties within the tanks would provide direction for efforts to reduce the frequency and severity of these events. In this report, the use of probabilistic finite element analyses for computing the probability of rollover and the sensitivity of rollover probability to various parameters is described.

Khaleel, M.A. [Pacific Northwest Lab., Richland, WA (United States); Cofer, W.F.; Al-fouqaha, A.A. [Washington State Univ., Pullman, WA (United States). Dept. of Civil and Environmental Engineering

1995-09-01T23:59:59.000Z

3

An evaluation of finite element models of stiffened plates subjected to impulsive loading  

E-Print Network (OSTI)

Different finite element models are evaluated for two very common structures, a cantilever beam and a stiffened plate, subjected to impulsive loading. For the cantilever beam case, the finite element models are one, two ...

Pedatzur, Omri

2004-01-01T23:59:59.000Z

4

A Finite Element Model for Simulation of Carbon Dioxide Sequestration  

SciTech Connect

We present a hydro-mechanical model, followed by stress, deformation, and shear-slip failure analysis for geological sequestration of carbon dioxide (CO2). The model considers the poroelastic effects by taking into account of the two-way coupling between the geomechanical response and the fluid flow process. Analytical solutions for pressure and deformation fields were derived for a typical geological sequestration scenario in our previous work. A finite element approach is introduced here for numerically solving the hydro-mechanical model with arbitrary boundary conditions. The numerical approach was built on an open-source finite element code Elmer, and results were compared to the analytical solutions. The shear-slip failure analysis was presented based on the numerical results, where the potential failure zone is identified. Information is relevant to the prediction of the maximum sustainable injection rate or pressure. The effects of caprock permeability on the fluid pressure, deformation, stress, and the shear-slip failure zone were also quantitatively studied. It was shown that a larger permeability in caprock and base rock leads to a larger uplift but a smaller shear-slip failure zone.

Bao, Jie; Xu, Zhijie; Fang, Yilin

2013-11-02T23:59:59.000Z

5

Finite-element modelling: a new tool for the biologist  

Science Journals Connector (OSTI)

...problem that excessive distortion of the applied skin will prevent adequate adhesion...Finite-element techniques have already been applied to problems associated with cochlear mechanics...position at the University Hospital, Utrecht, The Netherlands, he moved to Bristol...

2000-01-01T23:59:59.000Z

6

Surface photovoltage measurements and finite element modeling of SAW devices.  

SciTech Connect

Over the course of a Summer 2011 internship with the MEMS department of Sandia National Laboratories, work was completed on two major projects. The first and main project of the summer involved taking surface photovoltage measurements for silicon samples, and using these measurements to determine surface recombination velocities and minority carrier diffusion lengths of the materials. The SPV method was used to fill gaps in the knowledge of material parameters that had not been determined successfully by other characterization methods. The second project involved creating a 2D finite element model of a surface acoustic wave device. A basic form of the model with the expected impedance response curve was completed, and the model is ready to be further developed for analysis of MEMS photonic resonator devices.

Donnelly, Christine

2012-03-01T23:59:59.000Z

7

Gauge invariance and the finite-element solution of the Schwinger model  

Science Journals Connector (OSTI)

We apply the method of finite elements to two-dimensional quantum electrodynamics. We construct gauge-invariant operator difference equations and compute the chiral anomaly in the Schwinger model. The relative error between the exact answer and the finite-element prediction vanishes like M-2, where M is the number of finite elements.

Carl M. Bender; Kimball A. Milton; David H. Sharp

1985-01-15T23:59:59.000Z

8

Constitutive model effects on finite element modeling of elastomer behavior in radial interference seal configurations  

E-Print Network (OSTI)

CONSTITUTIVE MODEL EFFECTS ON FINITE ELEMENT MODELING OF ELASTOMER BEHAVIOR IN RADIAL INTERFERENCE SEAL CONFIGURATIONS A Thesis by JASON R. JACKSON Subnutted to the Office of Graduate Studies of Texas A&M University in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE August 1996 Major Subject: Mechanical Engineering CONSTITUTIVE MODEL EFFECTS ON FINITE ELEMENT MODELING OF ELASTOMER BEHAVIOR IN RADIAL INTERFERENCE SEAL CONFIGURATIONS A Thesis by JASON R. JACKSON...

Jackson, Jason R.

1996-01-01T23:59:59.000Z

9

Calibration under uncertainty for finite element models of masonry monuments  

SciTech Connect

Historical unreinforced masonry buildings often include features such as load bearing unreinforced masonry vaults and their supporting framework of piers, fill, buttresses, and walls. The masonry vaults of such buildings are among the most vulnerable structural components and certainly among the most challenging to analyze. The versatility of finite element (FE) analyses in incorporating various constitutive laws, as well as practically all geometric configurations, has resulted in the widespread use of the FE method for the analysis of complex unreinforced masonry structures over the last three decades. However, an FE model is only as accurate as its input parameters, and there are two fundamental challenges while defining FE model input parameters: (1) material properties and (2) support conditions. The difficulties in defining these two aspects of the FE model arise from the lack of knowledge in the common engineering understanding of masonry behavior. As a result, engineers are unable to define these FE model input parameters with certainty, and, inevitably, uncertainties are introduced to the FE model.

Atamturktur, Sezer,; Hemez, Francois,; Unal, Cetin

2010-02-01T23:59:59.000Z

10

Finite element modeling of nonlinear vibration behavior of piezo-integrated structures  

Science Journals Connector (OSTI)

This paper aims at finite element modeling of nonlinear vibration behavior of piezo-integrated structures subjected to weak electric field. This nonlinear vibration behavior was observed in the form of dependence of resonance frequency on the vibration ... Keywords: Finite element modeling, Modal reduction, Newmark method, Nonlinear vibration, Piezo-integrated structures

Sandeep Kumar Parashar; Utz Von Wagner; Peter Hagedorn

2013-04-01T23:59:59.000Z

11

A mixed finite-element scheme of a semiconductor energy-transport model  

E-Print Network (OSTI)

A mixed finite-element scheme of a semiconductor energy-transport model using dual entropy variables Stephan Gadau, Ansgar J¨ungel, and Paola Pietra Abstract. One-dimensional stationary energy employing a mixed-hybrid finite- element method which has the advantage to fulfill current conser- vation

Hanke-Bourgeois, Martin

12

Initial Testing of a Two-Dimensional Finite Element Model for Floodplain Inundation  

Science Journals Connector (OSTI)

8 January 1994 research-article Initial Testing of a Two-Dimensional Finite Element Model for Floodplain...expectations and the need for improved data acquisition for model testing is highlighted. On the basis of these numerical experiments...

1994-01-01T23:59:59.000Z

13

A FINITE ELEMENT MODEL FOR THE TIME-DEPENDENT JOULE HEATING PROBLEM*  

E-Print Network (OSTI)

.3) 0 system models the electric heating* *ial differential equation describing the electric heating of a conducting body. We prove err* *or A FINITE ELEMENT MODEL FOR THE TIME-DEPENDENT JOULE HEATING PROBLEM

Larsson, Stig

14

Finite Element Modelling and Molecular Dynamic Simulations of Carbon nanotubes/ Polymer Composites  

E-Print Network (OSTI)

Modeling of single-walled carbon nanotubes, multi-walled nanotubes and nanotube reinforced polymer composites using both the Finite Element method and the Molecular Dynamic simulation technique is presented. Nanotubes subjected to mechanical loading...

Gaddamanugu, Dhatri

2010-07-14T23:59:59.000Z

15

Finite element decomposition and grid generation for brain modeling and visualization  

E-Print Network (OSTI)

Numerical grid generation is used to provide a framework for brain and neuron visualization. Smoothing spline surfaces are fit to contour data to generate 3D solid model reconstruction of brain tissues. Finite element methods are then used...

Batte, David Allan

2012-06-07T23:59:59.000Z

16

TEA - a linear frequency domain finite element model for tidal embayment analysis  

E-Print Network (OSTI)

A frequency domain (harmonic) finite element model is developed for the numerical prediction of depth average circulation within small embayments. Such embayments are often characterized by irregular boundaries and bottom ...

Westerink, Joannes J.

1984-01-01T23:59:59.000Z

17

The representation of boundary currents in a finite element shallow water model  

E-Print Network (OSTI)

We evaluate the influence of local resolution, eddy viscosity, coastline structure, and boundary conditions on the numerical representation of boundary currents in a finite element shallow-water model. The use of finite element discretization methods offers a higher flexibility compared to finite difference and finite volume methods, that are mainly used in previous publications. This is true for the geometry of the coast lines and for the realization of boundary conditions. For our investigations we simulate steady separation of western boundary currents from idealized and realistic coast lines. The use of grid refinement allows a detailed investigation of boundary separation at reasonable numerical cost.

Düben, Peter D

2015-01-01T23:59:59.000Z

18

A Mixed Finite-Element Discretization of the Energy-Transport Model for Semiconductors  

E-Print Network (OSTI)

A Mixed Finite-Element Discretization of the Energy-Transport Model for Semiconductors Stefan Holst #12;tting mixed #12;nite-element method is used to discretize the stationary energy. Energy-transport models describe the ow of electrons through a semi- conductor device, in uenced by di

Pietra, Paola

19

CALIBRATION OFTHE FINITE ELEMENT MODEL OFA TWELVE-SPAN PRESTRESSED CONCRETE BRIDGE USING  

E-Print Network (OSTI)

CALIBRATION OFTHE FINITE ELEMENT MODEL OFA TWELVE-SPAN PRESTRESSED CONCRETE BRIDGE USING AMBIENT health monitoring system was designed and installed in the bridge. As a critical part in the SHM process the implementation of the FE model calibration using ambient vibration data. The initial model of the bridge

Paris-Sud XI, Université de

20

Finite element modeling of heat and mass transport in aquifers  

E-Print Network (OSTI)

of the grid test problem transient temperature distribution using upstream weighting to the solution of Avdonin (1964)(linear elements). 60 Comparison of the radial test problem transient temperature profile using upstream weighting to the solution... of Avdonin (1964)(linear elements) . . 61 12 13 Comparison of the grid problem transient temperature profile using mass lumping to the solution of Avdonin (1964). Comparison of the grid problem temperature progression using mass lumping to the solution...

Grubaugh, Elston Kent

1980-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling finite element" 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

Coupled axisymmetric finite element model of a hydraulically amplified magnetostrictive actuator for active powertrain mounts  

Science Journals Connector (OSTI)

A coupled axisymmetric finite element model is formulated to describe the dynamic performance of a hydraulically amplified magnetostrictive actuator for active powertrain mounts. The formulation is based on the weak form representations of Maxwell's ... Keywords: Active powertrain mount, Actuator, Axisymmetric model, Magnetostriction, Terfenol-D

Suryarghya Chakrabarti; Marcelo J. Dapino

2012-11-01T23:59:59.000Z

22

On a tensor-based finite element model for the analysis of shell structures  

E-Print Network (OSTI)

In the present study, we propose a computational model for the linear and nonlinear analysis of shell structures. We consider a tensor-based finite element formulation which describes the mathematical shell model in a natural and simple way by using...

Arciniega Aleman, Roman Augusto

2006-04-12T23:59:59.000Z

23

A Finite-Element Model for Simulation of Carbon Dioxide Sequestration  

SciTech Connect

Herein, we present a coupled thermal-hydro-mechanical model for geological sequestration of carbon dioxide followed by the stress, deformation, and shear-slip failure analysis. This fully coupled model considers the geomechanical response, fluid flow, and thermal transport relevant to geological sequestration. Both analytical solutions and numerical approach via finite element model are introduced for solving the thermal-hydro-mechanical model. Analytical solutions for pressure, temperature, deformation, and stress field were obtained for a simplified typical geological sequestration scenario. The finite element model is more general and can be used for arbitrary geometry. It was built on an open-source finite element code, Elmer, and was designed to simulate the entire period of CO2 injection (up to decades) both stably and accurately—even for large time steps. The shear-slip failure analysis was implemented based on the numerical results from the finite element model. The analysis reveals the potential failure zone caused by the fluid injection and thermal effect. From the simulation results, the thermal effect is shown to enhance well injectivity, especially at the early time of the injection. However, it also causes some side effects, such as the appearance of a small failure zone in the caprock. The coupled thermal-hydro-mechanical model improves prediction of displacement, stress distribution, and potential failure zone compared to the model that neglects non-isothermal effects, especially in an area with high geothermal gradient.

Bao, Jie; Xu, Zhijie; Fang, Yilin

2014-09-01T23:59:59.000Z

24

Development and applications of two finite element groundwater flow and contaminant transport models: FEWA and FEMA  

SciTech Connect

This paper presents the construction, verification, and application of two groundwater flow and contaminant transport models: A Finite Element Model of Water Flow through Aquifers (FEWA) and A Finite Element Model of Material Transport through Aquifers (FEMA). The construction is based on the finite element approximation of partial differential equations of groundwater flow (FEWA) and of solute movement (FEMA). The particular features of FEWA and FEMA are their versatility and flexibility for dealing with nearly all vertically integrated two-dimensional problems. The models were verified against both analytical solutions and widely used US Geological Survey finite difference approximations. They were then applied for calibration and validation, using data obtained in experiments at the Engineering Test Facility at Oak Ridge National Laboratory. Results indicated that the models are valid for this specific site. To demonstrate the versatility anf flexibility of the models, they were applied to two hypothetical, but realistic, complex problems and three field sites across the United States. In these applications the models yielded good agreement with the field data for all three sites. Finally, the predictive capabilities of the models were demonstrated using data obtained at the Hialeah Preston site in Florida. This case illustrates the capability of FEWA and FEMA as predictive tools and their usefulness in the management of groundwater flow and contaminant transport. 25 refs.

Yeh, G.T.; Wong, K.V.; Craig, P.M.; Davis, E.C.

1985-01-01T23:59:59.000Z

25

Heat Transport in Groundwater Systems--Finite Element Model  

E-Print Network (OSTI)

into groundwater aquifers for long term energy storage. Analytical solutions are available that predict water temperatures as hot water is injected into a groundwater aquifer, but little field and laboratory data are available to verify these models. The objectives...

Grubaugh, E. K.; Reddell, D. L.

26

Finite Element Modeling of the Fastening Systems and the Concrete  

E-Print Network (OSTI)

Sleeper and Ballast 0 500 1000 1500 2000 2500 3000 3500 4000 0.0000 0.0002 0.0004 0.0006 0.0008 0 of strands Rail seat area is between 0.39 m to 0.67 m Rail Seat Area Component Modeling: Concrete Sleeper Seat Area Position of concrete surface strain lt = 0.48 m Component Modeling: Concrete Sleeper

Barkan, Christopher P.L.

27

How does trench coupling lead to mountain building in the Subandes? A viscoelastoplastic finite element model  

E-Print Network (OSTI)

How does trench coupling lead to mountain building in the Subandes? A viscoelastoplastic finite element model Gang Luo1 and Mian Liu1 Received 10 June 2008; revised 3 December 2008; accepted 2 February cause of the Andean mountain building. The present-day crustal shortening in the Andes is clear from

Liu, Mian

28

A Finite Element Model for Ice Ball Evolution in a Multi-probe Cryosurgery  

E-Print Network (OSTI)

to intracellular ice injury for fast cooling rates, and solution effects injury for slow cooling rates. BasicallyA Finite Element Model for Ice Ball Evolution in a Multi-probe Cryosurgery RICHARD WANa, *, ZHIHONG October 2002; In final form 8 May 2003) The ice formation in a water body is examined for the computation

Wan, Richard G.

29

Long range propagation modeling of offshore wind turbine noise using finite element and parabolic equation models  

Science Journals Connector (OSTI)

Noise generated by offshore wind turbines and support structures radiates and propagates through the air water and sediment. Predicting noise levels around wind turbine structures at sea is required to estimate the effects of the noise on marine life. We used Finite Element(FE) and Parabolic Equation (PE) models to predict long range propagation of noise from the construction and operation of offshore wind turbines.FEanalysis produced pressure outputs at short ranges were used as a starting field for a modified PE propagation model. Furthermore we investigated the optimum range for the transition to PE modeling. The effects of various sediment types were also considered determining the pressure starting field. In FEanalysis models we implemented the axisymmetric elements and implicit dynamic analysis with pressureimpact loading and vertical acceleration boundary conditions to simulate pile driving and operational noise radiation. We will present the PE long range pressure field outputs from the offshore pile driving and operation for a shallow water environment around Block Island Rhode Island.

Huikwan Kim; Gopu R. Potty; James H. Miller; Kevin B. Smith; Georges Dossot

2012-01-01T23:59:59.000Z

30

Implementation of surface tension with wall adhesion effects in a three-dimensional finite element model for fluid flow  

E-Print Network (OSTI)

- 1 - Implementation of surface tension with wall adhesion effects in a three-dimensional finite element modelling of surface tension. The external stress vectors associated with surface tension a drop of liquid on a plane is treated. Keywords : surface tension, finite element method, average

Boyer, Edmond

31

Finite element model-simulation-based characterization of a magnetostrictive gyrosensor  

SciTech Connect

This paper analyzes a prototype microgyrosensor that employs the magnetostrictive alloy Galfenol for transduction of Coriolis-induced forces into an electrical output for quantifying a given angular velocity. The magnetic induction distribution in the Galfenol sensor patch depends on its bending shape and magnetoelastic properties and is investigated using a finite element model. Fluctuations in magnetic induction caused by a sinusoidal rotation of the sensor produce an amplitude modulated voltage in a surrounding coil which is simulated and measured.

Marschner, U. [Institute for Semiconductor and Microsystems Technology, Technische Universitaet Dresden, 01062 Dresden (Germany); Graham, F.; Yoo, J.-H.; Flatau, A. B. [Department of Aerospace Engineering, University of Maryland, College Park, Maryland 20742 (United States); Mudivarthi, C. [Department of Materials Science and Engineering, University of Maryland, College Park, Maryland 20742 (United States); Neubert, H. [Institute for Electromechanical and Electronic Design, Technische Universitaet Dresden, 01062 Dresden (Germany)

2010-05-15T23:59:59.000Z

32

Electrical-Thermal-Structural Coupled Finite Element Model of High Temperature Superconductor for Resistive Type Fault Current Limiters  

Science Journals Connector (OSTI)

A multi-physics finite element model of high-temperature superconductors (HTS) will be presented in this article. The electrical-thermal model is mainly based on Maxwell’s equation and basic heat transfer equa...

J. Sheng; Y. Chen; B. Lin; L. Ying; Z. Jin…

2014-06-01T23:59:59.000Z

33

Three-dimensional finite-element model for simulating water flow in variability saturated porous media  

SciTech Connect

A three-dimensional finite-element model for simulating water flow in variably saturated porous media is presented. The model formulation is general and capable of accommodating complex boundary conditions associated with seepage faces and infiltration or evaporation on the soil surface. Included in this formulation is an improved Picard algorithm designed to cope with severely nonlinear soil moisture relations. The algorithm is formulated for both rectangular and triangular prism elements. The element matrices are evaluated using an influence coefficient technique that avoids costly numerical integration. Spatial discretization of a three-dimensional regions is performed using a vertical slicing approach designed to accommodate complex geometry with irregular boundaries, layering, and/or lateral discontinuities. Matrix solution is achieved using a slice successive overrelaxation scheme that permits a fairly large number of nodal unknowns (on the order of several thousand) to be handled efficiently on small minicomputers. Six examples are presented to verify and demonstrate the utility of the proposed finite-element model. The first four examples concern one- and two-dimensional flow problems used as sample problems to benchmark the code. The remaining examples concern three-dimensions problems. These problems are used to illustrate the performance of the proposed algorithm in three-dimensional situations involving seepage faces and anisotropic soil media.

Huyakorn, P.S.; Springer, E.P.; Guvanasen, V.; Wadsworth, T.D.

1986-12-01T23:59:59.000Z

34

A new class of finite element variational multiscale turbulence models for incompressible magnetohydrodynamics  

E-Print Network (OSTI)

New large eddy simulation (LES) turbulence models for incompressible magnetohydrodynamics (MHD) derived from the variational multiscale (VMS) formulation for finite element simulations are introduced. The new models include the variational multiscale formulation, a residual-based eddy viscosity model, and a mixed model that combines both of these component models. Each model contains terms that are proportional to the residual of the incompressible MHD equations and is therefore numerically consistent. Moreover, each model is also dynamic, in that its effect vanishes when this residual is small. The new models are tested on the decaying MHD Taylor Green vortex at low and high Reynolds numbers. The evaluation of the models is based on comparisons with available data from direct numerical simulations (DNS) of the time evolution of energies as well as energy spectra at various discrete times. A numerical study, on a sequence of meshes, is presented that demonstrates that the large eddy simulation approaches the ...

Sondak, David; Oberai, Assad A; Pawlowski, Roger P; Cyr, Eric C; Smith, Tom M

2014-01-01T23:59:59.000Z

35

Modeling of reactor components using FIDAP: a finite element computer code  

E-Print Network (OSTI)

. ? e model are listed in table 1. 19 CHAPTER III FLUID AND THERMAL MIXING IN THE COLD LEG AND DOWNCOMER OF A PWR - A BENCHMARK In order to vahdste the code FIDAP, s, thermal mixing experiment is simulated This is basically a test of the field...MODELING OF REACTOR COMPONENTS USING FIDAP - A FINITE ELEMENT COMPUTE& CODE A Thesrs by ANAND GANGADHARAN Subnutted to the Office of Graduate Stuches of Texs, s ARM University in partial fulfillment of the requirements for the degree...

Gangadharan, Anand

2012-06-07T23:59:59.000Z

36

Defmod - Parallel multiphysics finite element code for modeling crustal deformation during the earthquake/rifting cycle  

E-Print Network (OSTI)

In this article, we present Defmod, a fully unstructured, two or three dimensional, parallel finite element code for modeling crustal deformation over time scales ranging from milliseconds to thousands of years. Defmod can simulate deformation due to all major processes that make up the earthquake/rifting cycle, in non-homogeneous media. Specifically, it can be used to model deformation due to dynamic and quasistatic processes such as co-seismic slip or dike intrusion(s), poroelastic rebound due to fluid flow and post-seismic or post-rifting viscoelastic relaxation. It can also be used to model deformation due to processes such as post-glacial rebound, hydrological (un)loading, injection and/or withdrawal of compressible or incompressible fluids from subsurface reservoirs etc. Defmod is written in Fortran 95 and uses PETSc's parallel sparse data structures and implicit solvers. Problems can be solved using (stabilized) linear triangular, quadrilateral, tetrahedral or hexahedral elements on shared or distribut...

Ali, S Tabrez

2014-01-01T23:59:59.000Z

37

A finite element model for transient thermal/structural analysis of large composite space structures  

E-Print Network (OSTI)

on approximate 6 analysis techniques based on finite elements has begun. Such techniques as reduced basis techniques and generalized transform methods offer hope of solving the finite element 8 equations more efficiently. An integrated thermal/structural... integrated analysis codes. However, Mahaney, Thornton, and Dechaumphai have identified require 5 ments for such thermal/structural programs. They concluded that such analysis methods should have the following five characteristics. First, a common finite...

Lutz, James Delmar

2012-06-07T23:59:59.000Z

38

Three-dimensional finite element modeling of a magnet array spinning above a conductor  

SciTech Connect

Drag forces due to eddy currents induced by the relative motion of a conductor and a magnetic field occur in many practical devices: motors, brakes, magnetic bearings, and magnetically levitated vehicles. Recently, finite element codes have included solvers for 3-D eddy current geometries and have the potential to be very useful in the design and analysis of these devices. In this paper, numerical results from three-dimensional modeling of a magnet array spinning above a conductor are compared to experimental results in order to assess the capabilities of these codes.

Lorimer, W.L.; Lieu, D.K. [Univ. of California, Berkeley, CA (United States). Dept. of Mechanical Engineering; Hull, J.R.; Mulcahy, T.M.; Rossing, T.D. [Argonne National Lab., IL (United States)

1993-12-31T23:59:59.000Z

39

Seismic wave propagation in coal seams: finite element modelling and field tests  

Science Journals Connector (OSTI)

In-seam seismic (ISS) refers to methods which utilise artificially generated channel waves trapped in coal seam to locate geologic disturbances and mine voids. It is one of the basic geophysical methods for underground survey. The advantage of ISS is that seismic energy is better preserved in coal seams and seismic waves can travel and be detected over much larger distances in comparison with body waves which radiate three-dimensionally. It is also convenient and reasonable to set up a two-dimensional model to study the wave propagation characteristics. Using a commercial finite element method (FEM) modelling software, both transmission and reflection tests were simulated. Field experiments of the ISS technology have been carried out at underground coal mines. The results demonstrated that two-dimensional FEM modelling appears to be a satisfactory approach for ISS simulation, and if used properly, ISS technology can successfully detect mine voids and geologic discontinuities.

Hongliang Wang; Maochen Ge

2014-01-01T23:59:59.000Z

40

Two-dimensional thermo-mechanical finite element model for laser cladding  

SciTech Connect

Temperature and stress fields during Laser Cladding determine, respectively, the microstructure and residual stress induced deformation and crack formation. As laser cladding processes find application in manufacturing, understanding of the temperature and stress fields becomes crucial for development of the relationship between process parameters and service behavior. A two-dimensional model of laser cladding is developed, using the finite element software package ABAQUS. It enables an investigation of the temperature field that develops at the center plane of the material. This temperature field provides the input for a thermal stress analysis, for which generalized plane strain was assumed. The goal of the present paper is to perform a quantitative evaluation of the residual stresses that develop at the two-layered material, as a function of process parameters such as scanning speed, laser power and powder feed rate. Results of the model are presented, as applied to cladding of C95600 on AA333.

Deus, A.M. de; Mazumder, J. [Univ. of Illinois, Urbana-Champaign, IL (United States)

1996-12-31T23:59:59.000Z

Note: This page contains sample records for the topic "modeling finite element" 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

Finite Element Analysis of the Amontons-Coulomb's Model using Local and Global Friction Tests  

SciTech Connect

In spite of the abundant number of experimental friction tests that have been reported, the contact with friction modeling persists to be one of the factors that determine the effectiveness of sheet metal forming simulation. This difficulty can be understood due to the nature of the friction phenomena, which comprises the interaction of different factors connected to both sheet and tools' surfaces. Although in finite element numerical simulations friction models are commonly applied at the local level, they normally rely on parameters identified based on global experimental tests results. The aim of this study is to analyze the applicability of the Amontons-Coulomb's friction coefficient identified using complementary tests: (i) load-scanning, at the local level and (ii) draw-bead, at the global level; to the numerical simulation of sheet metal forming processes.

Oliveira, M. C.; Menezes, L. F.; Ramalho, A. [CEMUC, Department of Mechanical Engineering, University of Coimbra, Polo II, Rua Luis Reis Santos, Pinhal de Marrocos, 3030-788 Coimbra (Portugal); Alves, J. L. [Department of Mechanical Engineering, University of Minho, Campus de Azurem, 4800-058, Guimaraes (Portugal)

2011-05-04T23:59:59.000Z

42

Finite-element modelling of YBCO fault current limiter with temperature dependent  

Science Journals Connector (OSTI)

In this paper, we present a numerical model which takes into account both the thermal and the electromagnetic aspects of the over-critical current regime for high-temperature superconducting (HTS) materials. The electromagnetic and thermal equations have been implemented in finite-element method (FEM) software in order to obtain a novel model for investigating the behaviour of the materials when the current exceeds Ic and the superconductor material goes to the normal state. The thermal dependence of the electrical parameters, such as the critical current density Jc, has been introduced. This model has been used to analyse the behaviour of strip lines of a YBCO/Au fault current limiter (FCL) on a sapphire substrate. Simulations with currents exceeding Ic have been performed, showing that the current limitation phase can be correctly reproduced. Such a model can be used to study the influence of the geometry on the performance of the FCL. It can replace experiments with currents exceeding Ic which may damage or destroy HTS samples and devices.

J Duron; F Grilli; L Antognazza; M Decroux; B Dutoit; Ø Fischer

2007-01-01T23:59:59.000Z

43

Quantum-corrected drift-diffusion models: Solution fixed point map and finite element approximation  

SciTech Connect

This article deals with the analysis of the functional iteration, denoted Generalized Gummel Map (GGM), proposed in [C. de Falco, A.L. Lacaita, E. Gatti, R. Sacco, Quantum-Corrected Drift-Diffusion Models for Transport in Semiconductor Devices, J. Comp. Phys. 204 (2) (2005) 533-561] for the decoupled solution of the Quantum Drift-Diffusion (QDD) model. The solution of the problem is characterized as being a fixed point of the GGM, which permits the establishment of a close link between the theoretical existence analysis and the implementation of a numerical tool, which was lacking in previous non-constructive proofs [N.B. Abdallah, A. Unterreiter, On the stationary quantum drift-diffusion model, Z. Angew. Math. Phys. 49 (1998) 251-275, R. Pinnau, A. Unterreiter, The stationary current-voltage characteristics of the quantum drift-diffusion model, SIAM J. Numer. Anal. 37 (1) (1999) 211-245]. The finite element approximation of the GGM is illustrated, and the main properties of the numerical fixed point map (discrete maximum principle and order of convergence) are discussed. Numerical results on realistic nanoscale devices are included to support the theoretical conclusions.

Falco, Carlo de [School of Mathematical Sciences, Dublin City University, Glasnevin, Dublin 9 (Ireland); Jerome, Joseph W. [Department of Mathematics, Northwestern University, 2033 Sheridan Road, Evanston, IL 60208-2730 (United States); Sacco, Riccardo [Dipartimento di Matematica 'F.Brioschi', Politecnico di Milano, via Bonardi 9, 20133 Milano (Italy)], E-mail: riccardo.sacco@polimi.it

2009-03-20T23:59:59.000Z

44

Minimizing EIT image artefacts from mesh variability in Finite Element Models  

E-Print Network (OSTI)

artefacts which occur in electrical impedance tomography (EIT) images due to limitations in finite element R B Lionheart2 1 Systems and Computer Engineering, Carleton University, Ottawa, Canada 2 School of Mathematics, University of Manchester, UK Abstract. Electrical Impedance Tomography solves an inverse problem

Adler, Andy

45

Electrical and thermal finite element modeling of arc faults in photovoltaic bypass diodes.  

SciTech Connect

Arc faults in photovoltaic (PV) modules have caused multiple rooftop fires. The arc generates a high-temperature plasma that ignites surrounding materials and subsequently spreads the fire to the building structure. While there are many possible locations in PV systems and PV modules where arcs could initiate, bypass diodes have been suspected of triggering arc faults in some modules. In order to understand the electrical and thermal phenomena associated with these events, a finite element model of a busbar and diode was created. Thermoelectrical simulations found Joule and internal diode heating from normal operation would not normally cause bypass diode or solder failures. However, if corrosion increased the contact resistance in the solder connection between the busbar and the diode leads, enough voltage potentially would be established to arc across micron-scale electrode gaps. Lastly, an analytical arc radiation model based on observed data was employed to predicted polymer ignition times. The model predicted polymer materials in the adjacent area of the diode and junction box ignite in less than 0.1 seconds.

Bower, Ward Isaac; Quintana, Michael A.; Johnson, Jay

2012-01-01T23:59:59.000Z

46

Finite element modelling of transport and drift effects in tokamak divertor and SOL  

SciTech Connect

A finite element code is used to simulate transport of a single-species plasma in the edge and divertor of a tokamak. The physical model is based on Braginskii`s fluid equations for the conservation of particles, parallel momentum, ion and electron energy. In modelling recycling, transport of neutral density and energy is treated in the diffusion approximation. The electrostatic potential is obtained from the generalized Ohm`s law. It is used to compute the electric field and the associated E x B drift. In a first approximation, transport is assumed to be ambipolar. The system of equations is discretized on an unstructured triangular mesh, thus permitting good spatial resolution near the X-point and an accurate description of divertor plates of arbitrary shape. Special care must be taken to prevent numerical corruption of the highly anisotropic thermal diffusion. Comparisons will be made between simulations and experimental results from TdeV. This will focus, in particular, on density and temperature profiles at the divertor plates, and on the plasma parallel velocity in the SOL. The asymmetry in the power deposited to the inner and outer divertors and the effect of magnetic field reversal will be considered. Comparisons with B2-Eirene simulation results will also be presented.

Simard, M.; Marchand, R. [INRS-Energie et Materiaux, Varennes, Quebec (Canada); Boucher, C.; Gunn, J.P. [Centre Canadien de Fusion Magnetique, Varennes, Quebec (Canada)] [and others

1996-12-31T23:59:59.000Z

47

Numerical modeling of buoyancy-driven flows in a rotating cylindrical cavity: Comparison of a finite element model with a spectral model  

SciTech Connect

A finite element model is developed for the prediction of the motion of rotating Boussinesq fluid driven by buoyancy. The computations are performed for the axisymmetric regime in an annular cavity for Reynolds number varying from 0 to 2,500. The results are compared with those of an earlier study of this problem using a spectral Tau-Chebyshev method. The good agreement found assesses the finite element model. Finally, a complementary convergence analysis gives the sensitivity of the model to mesh refinement.

Jaeger, M.; Medale, M.; Randriamanpianina, A. [Centre National de la Recherche Scientifique, Marseille (France)

1996-12-01T23:59:59.000Z

48

Utilization of a finite element model to verify spent nuclear fuel storage rack welds  

SciTech Connect

Elastic and plastic finite element analyses were performed for the inner tie block assembly of a 25 port fuel rack designed for installation at the Idaho National Engineering and Environmental Laboratory (INEEL) Idaho Chemical Processing Plant (ICPP). The model was specifically developed to verify the adequacy of certain welds joining components of the fuel storage rack assembly. The work scope for this task was limited to an investigation of the stress levels in the inner tie welds when the rack was subjected to seismic loads. Structural acceptance criteria used for the elastic calculations performed were as defined by the rack`s designer. Structural acceptance criteria used for the plastic calculations performed as part of this effort were as defined in Subsection NF and Appendix F of Section III of the ASME Boiler and Pressure Vessel Code. The results confirm that the welds joining the inner tie block to the surrounding rack structure meet the acceptance criteria. The analysis results verified that the inner tie block welds should be capable of transferring the expected seismic load without structural failure.

Nitzel, M.E.

1998-07-01T23:59:59.000Z

49

Development of a three-dimensional finite element model of a horse's foot  

E-Print Network (OSTI)

of a horse's foot and attempt to validate it using experimentally obtamed strain results. A Suite element model was constructed using geometric data &om traced outlines of slices cut lrom an actual foot. The model was analyzed using the ABAQUS Suite... element analysis code and strain results were obtamed which were found to difFer signi6cantly &om experimental resuhs. Based on iinformation from the literature, it was determmed that the structure of the model is essentially sound and discrepancies...

Hanft, Joseph Thomas

2012-06-07T23:59:59.000Z

50

Virtual dynamic balancing method without trial weights for multi-rotor series shafting based on finite element model analysis  

Science Journals Connector (OSTI)

The traditional influence coefficient dynamic balancing method for multi-rotor series shafting such as turbine-generator sets gas turbines compressor trains and others usually needs to startup many times using trial weights along the rotor. Based on finite element model analysis for the multi-rotor series shafting a virtual dynamic balancing methodology which only needs to collect data of vibration response at operating speed without trial weights is developed in this paper. According to shafting structure and operating parameters the dynamic finite element model was built by using rotor dynamics theory and finite element simulation technology. The shafting dynamic characteristics and weighted influence coefficient matrix can be gotten by exciting virtual unbalance force on the balance place correspondingly. The effectiveness and flexibility of the proposed method have been illustrated by solving a shafting dynamic balancing example with no trial weights requirements. It is believed that the new methods developed in this work will help in reducing the time and cost of the equipment manufacturer or field dynamic balancing procedures.

2014-01-01T23:59:59.000Z

51

A Full-wave Model for Wave Propagation and Dissipation in the Inner Magnetosphere Using the Finite Element Method  

SciTech Connect

A wide variety of plasma waves play an important role in the energization and loss of particles in the inner magnetosphere. Our ability to understand and model wave-particle interactions in this region requires improved knowledge of the spatial distribution and properties of these waves as well as improved understanding of how the waves depend on changes in solar wind forcing and/or geomagnetic activity. To this end, we have developed a two-dimensional, finite element code that solves the full wave equations in global magnetospheric geometry. The code describes three-dimensional wave structure including mode conversion when ULF, EMIC, and whistler waves are launched in a two-dimensional axisymmetric background plasma with general magnetic field topology. We illustrate the capabilities of the code by examining the role of plasmaspheric plumes on magnetosonic wave propagation; mode conversion at the ion-ion and Alfven resonances resulting from external, solar wind compressions; and wave structure and mode conversion of electromagnetic ion cyclotron waves launched in the equatorial magnetosphere, which propagate along the magnetic field lines toward the ionosphere. We also discuss advantages of the finite element method for resolving resonant structures, and how the model may be adapted to include nonlocal kinetic effects.

Ernest Valeo, Jay R. Johnson, Eun-Hwa and Cynthia Phillips

2012-03-13T23:59:59.000Z

52

Operator-adapted finite element wavelets : theory and applications to a posteriori error estimation and adaptive computational modeling  

E-Print Network (OSTI)

We propose a simple and unified approach for a posteriori error estimation and adaptive mesh refinement in finite element analysis using multiresolution signal processing principles. Given a sequence of nested discretizations ...

Sudarshan, Raghunathan, 1978-

2005-01-01T23:59:59.000Z

53

Orientation dependent tensile deformation behavior of two-phase laminate composites: Model analysis and finite element results  

SciTech Connect

A model is presented which allows the distribution of stresses and strains within a two-phase laminate to be determined as a function of the angle between the normal vector to the laminate interfaces and the tensile axis during elastic and elastic-plastic deformation. The model is applied to {alpha}{sub 2}(Ti{sub 3}Al)/{gamma}(TiAl) and, for comparison, to Al/Al{sub 2}O{sub 3} laminates in order to study (a) the transfer of stresses between the two phases due to the mutual deformation constraint at the interphase boundaries and (b) the dependence of the yield stress on the orientation of the lamellae with respect to the tensile axis. The model predictions are in good agreement with the results of finite element computations within the composite except for certain boundary layers at the outer surfaces.

Mertins, H.; Lahann, H.J. [GKSS-Forschungszentrum Geesthacht GmbH (Germany). Inst. fuer Werkstofforschung] [GKSS-Forschungszentrum Geesthacht GmbH (Germany). Inst. fuer Werkstofforschung

1996-03-01T23:59:59.000Z

54

On simple and accurate finite element models for nonlinear bending analysis of beams and plates  

E-Print Network (OSTI)

T x; dQTxx dx = ¡q(x) MTxx = Dxxd` T dx ; Q T x = AxzKs `T + dw T 0 dx ¶ (2.5a) 16 † The Reddy Beam Theory (RBT) dMRxx dx = Q R x +fi dPxx dx ¡flRx (2.6a) dQRx dx = q(x)+fl dRxx dx ¡fi d2Pxx dx2 (2.6b) MRxx = Dxxd` R dx ¡fiFxx d`R dx + d2wR0 dx2... >: ˆT for TBT U = „Dxx`RD xx ¡fiFxxdw R 0dx for simplifled RBT (2.12) A = 8 >>>> >> >: Dxx AxzKs for TBT ^Dxx „Axz for simplifled RBT (2.13) 18 B = 8> >>> >> >: 0 for TBT ^Dxx „Axz for simplifled RBT (2.14) II.2.3. A unifled flnite element model...

Urthaler Lapeira, Yetzirah Yksya

2007-09-17T23:59:59.000Z

55

Mid-rise Building Progressive Collapse Finite Element Modeling with Consideration of Occupant Egress.  

E-Print Network (OSTI)

??A progressive collapse is characterized by initial local damage to a structural element leading to collapse of a large portion of the structure. Recently, investigation… (more)

Gabay, Zachary

2012-01-01T23:59:59.000Z

56

Finite Element Modelling of the Sawing of DC Cast AA2024 Aluminium Alloy Slabs  

SciTech Connect

In the semi-continuous casting of large cross-section rolling sheet ingots of high-strength aluminum alloys (2xxx and 7xxx series), the control of the residual (internal) stresses generated by the non-uniform cooling becomes a necessity. These stresses must be relieved by a thermal treatment before the head and foot of the ingot can be cut. Otherwise, the saw can be caught owing to compressive stresses or cut parts may be ejected thus injuring people or damaging equipment. These high added-value ingots need to be produced in secure conditions. Moreover, a better control of the sawing procedure could allow the suppression of the thermal treatment and therefore save time and energy. By studying the stress build-up during casting and the stress relief during sawing, key parameters for the control and optimization of the processing steps, can be derived. To do so, the direct chill (DC) casting of the AA2024 alloy is modeled with ABAQUS 6.5 with special attention to the thermo-mechanical properties of the alloy. The sawing operation is then simulated by removing mesh elements so as to reproduce the progression of the saw in the ingot. Preliminary results showing the stress relief during sawing accompanied by the risk of saw blocking due to compression or initiating a crack ahead of the saw, are analyzed with an approach based on the rate of strain energy release.

Drezet, J.-M. [Computational Materials Laboratory, School of Engineering, Ecole Polytechnique Federale de Lausanne, Station 12, CH-1015 Lausanne (Switzerland); Ludwig, O. [Calcom-ESI SA, PSE-A, CH-1015 Lausanne (Switzerland); Heinrich, B. [Alcan Aluminium Valais SA, CH3960 Sierre (Switzerland)

2007-04-07T23:59:59.000Z

57

Finite element modeling of the temperature rise due to the propagation of ultrasonic waves in viscoelastic materials and experimental validation  

Science Journals Connector (OSTI)

The ultrasound stimulated thermography method is usually used to detect the temperature rise at a defect position. The temperature rise can be due to the friction between the edges of the defect and/or the plastic deformation around the defect. This paper presents another aspect of the method when the ultrasounds are propagating in a viscoelasticanisotropicmaterial such as polymers or fiber-reinforced polymers. The attenuation of the waves produces a distributed temperature field. Therefore even a defect that does not produce some heat can be detected the ultrasonic field is modified. A finite element model is used for computing the temperature field and for predicting the possibility for an infrared camera of detecting the temperature rise and its modification due to a defect. The model computes the stress and displacement fields associated with the propagation and the loss of energy. Then the heat equation is solved with this loss as a source of heating. An experiment is done with a sonotrode that excites a PVC plate. The ultrasonic displacement at the top of the plate is measured with a laser velocimeter and introduced in the model. Finally the model result is compared to the image produced by the camera.

B. Hosten; C. Bacon; C. Biateau

2008-01-01T23:59:59.000Z

58

Climbing elements in finite coxeter groups  

E-Print Network (OSTI)

We define the notion of a climbing element in a finite real reflection group relative to a total order on the reflection set and we characterise these elements in the case where the total order arises from a bipartite Coxeter element.

Brady, Thomas; Watt, And Colum

2010-01-01T23:59:59.000Z

59

Finite element analysis of multilayer coextrusion.  

SciTech Connect

Multilayer coextrusion has become a popular commercial process for producing complex polymeric products from soda bottles to reflective coatings. A numerical model of a multilayer coextrusion process is developed based on a finite element discretization and two different free-surface methods, an arbitrary-Lagrangian-Eulerian (ALE) moving mesh implementation and an Eulerian level set method, to understand the moving boundary problem associated with the polymer-polymer interface. The goal of this work is to have a numerical capability suitable for optimizing and troubleshooting the coextrusion process, circumventing flow instabilities such as ribbing and barring, and reducing variability in layer thickness. Though these instabilities can be both viscous and elastic in nature, for this work a generalized Newtonian description of the fluid is used. Models of varying degrees of complexity are investigated including stability analysis and direct three-dimensional finite element free surface approaches. The results of this work show how critical modeling can be to reduce build test cycles, improve material choices, and guide mold design.

Hopkins, Matthew Morgan; Schunk, Peter Randall; Baer, Thomas A. (Proctor & Gamble Company, West Chester, OH); Mrozek, Randy A. (Army Research Laboratory, Adelphi, MD); Lenhart, Joseph Ludlow (Army Research Laboratory, Adelphi, MD); Rao, Rekha Ranjana; Collins, Robert (Oak Ridge National Laboratory); Mondy, Lisa Ann

2011-09-01T23:59:59.000Z

60

An elastic-perfectly plastic flow model for finite element analysis of perforated materials  

SciTech Connect

This paper describes the formulation of an elastic-perfectly plastic flow theory applicable to equivalent solid [EQS] modeling of perforated materials. An equilateral triangular array of circular penetrations is considered. The usual assumptions regarding geometry and loading conditions applicable to the development of elastic constants for EQS modeling of perforated plates are considered to apply here. An elastic-perfectly plastic [EPP] EQS model is developed for a collapse surface that includes fourth-order stress terms. The fourth order yield function has been shown to be appropriate for plates with a triangular array of circular holes. A complete flow model is formulated using the consistent tangent modulus approach based on the fourth order yield function.

Jones, D.P.; Gordon, J.L.; Hutula, D.N.; Banas, D.; Newman, J.B.

1999-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling finite element" 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

A multi-scale iterative approach for finite element modeling of thermal contact resistance  

E-Print Network (OSTI)

Surface topography has long been considered a key factor in the performance of many contact applications including thermal contact resistance. However, essentially all analytical and numerical models of thermal contact ...

Thompson, Mary Kathryn, 1980-

2007-01-01T23:59:59.000Z

62

A Lyapunov Exponent Approach for Identifying Chaotic Behavior in a Finite Element Based Drillstring Vibration Model  

E-Print Network (OSTI)

The purpose of this work is to present a methodology to predict vibrations of drilllstrings for oil recovery service. The work extends a previous model of the drill collar between two stabilizers in the literature to include drill collar flexibility...

Mongkolcheep, Kathira

2010-10-12T23:59:59.000Z

63

Three-dimensional DC anisotropic resistivity modelling using finite elements on unstructured grids  

Science Journals Connector (OSTI)

......model as an example, the memory cost using the U2 grid is around one-tenth...as heat exchanger to exploit the geothermal energy. Within regional stress systems...consequently, lowers the computational costs significantly. A singularity removal......

Wei Wang; Xiaoping Wu; Klaus Spitzer

2013-01-01T23:59:59.000Z

64

CONVERGENCE OF A MULTISCALE FINITE ELEMENT METHOD ...  

E-Print Network (OSTI)

Mar 3, 1999 ... In this paper, we consider solving a class of two-dimensional, second order, el- liptic boundary ... a standard finite element or finite difference method is used to solve the equations, the degrees of ..... terfaces. The result depends on the geometry of the jump interfaces. ...... a measure of the relative error.

1999-04-17T23:59:59.000Z

65

Improved detection of rough defects for ultrasonic NDE inspections based on finite element modeling of elastic wave scattering  

SciTech Connect

Defects which posses rough surfaces greatly affect ultrasonic wave scattering behaviour, often reducing the magnitude of reflected signals. Ultrasonic inspections rely upon this response for detecting and sizing flaws. For safety critical components reliable characterisation is crucial. Therefore, providing an accurate means to predict reductions in signal amplitude is essential. An extension of Kirchhoff theory has formed the basis for the UK power industry inspection justifications. However, it is widely recognised that these predictions are pessimistic owing to analytical approximations. A numerical full field modelling approach does not fall victim to such limitations. Here, a Finite Element model is used to aid in setting a non-conservative reporting threshold during the inspection of a large pressure vessel forging that might contain embedded rough defects. The ultrasonic response from multiple rough surfaces defined by the same statistical class is calculated for normal incident compression waves. The approach is validated by comparing coherent scattering with predictions made by Kirchhoff theory. At lower levels of roughness excellent agreement is observed, whilst higher values confirm the pessimism of Kirchhoff theory. Furthermore, the mean amplitude in the specular direction is calculated. This represents the information obtained during an inspection, indicating that reductions due to increasing roughness are significantly less than the coherent component currently being used.

Pettit, J. R. [Rolls-Royce Nuclear, PO BOX 2000, Derby, UK, DE21 7XX and Research Centre for NDE, Imperial College London, Exhibition Road, London SW7 2AZ (United Kingdom); Walker, A. [Rolls-Royce Nuclear, PO BOX 2000, Derby DE21 7XX (United Kingdom); Lowe, M. J. S. [Research Centre for NDE, Imperial College London, Exhibition Road, London SW7 2AZ (United Kingdom)

2014-02-18T23:59:59.000Z

66

Modeling Slag Penetration and Refractory Degradation Using the Finite Element Method  

SciTech Connect

Refractory degradation due to slag penetration can significantly reduce the service life of gasifier refractory linings. This paper describes a modeling approach that was developed to predict refractory spalling as a function of operating temperature, coal feedstock and refractory type. The model simulates the coupled thermal, diffusion, and mechanical interactions of coal slag with refractory ceramics. The heat transfer and slag diffusion solutions are directly coupled through a temperature-dependent effective diffusivity for slag penetration. The effective diffusivity is defined from slag penetration tests conducted in our laboratories on specific coal slag and refractory combinations. Chemically-induced swelling of the refractory and the build-up of mechanical stresses are functions of the slag penetration. The model results are compared with analytical spalling models and validated by experimental data in order to develop an efficient refractory degradation model for implementation in a systems level gasifier model. The ultimate goal of our research is to provide a tool that will help optimize gasifier performance by balancing conversion efficiency with refractory life.

Johnson, Kenneth I.; Williford, Ralph E.; Matyas, Josef; Pilli, Siva Prasad; Sundaram, S. K.; Korolev, Vladimir N.

2008-09-01T23:59:59.000Z

67

Patient specific finite element model of the face soft tissues for computer-assisted  

E-Print Network (OSTI)

(dental models) and radiology (cephalometry). This paper presents a complete protocol for computer of the dental occlusion, and aesthetic, with morphometric criterion that run out of a norm (face asym- metry a planning based only on skull and dental analysis. Moreover, one of the main patient requests is a reliable

Paris-Sud XI, Université de

68

Calcolo 43: 197215, 2006 A FINITE ELEMENT MODEL FOR MARTENSITIC THIN FILMS  

E-Print Network (OSTI)

is a measure of interfacial energy per unit area, (F, , c) is a composition-dependent free energy density, c energy for martensitic crystals is given. The energy density models the softening of the elastic modulus controlling the low-energy path from the cubic to the tetragonal lattice, the loss of stability

Luskin, Mitchell

69

Finite Element Modeling of Suspended Particle Migration in Non-Newtonian Fluids  

SciTech Connect

Shear-induced migration of particles is studied during the slow flow of suspensions of spheres (particle volume fraction {phi} = 0.50) in an inelastic but shear-thinning, suspending fluid in flow between counterrotating concentric cylinders, The conditions are such that nonhydrodynamic effects are negligible. The movement of particles away from the high shear rate region is more pronounced than in a Newtonian suspending liquid. We test a continuum constitutive model for the evolution of particle concentration in a flowing suspension proposed by Phillips et al. (1992) by using shear-thinning, suspending fluids. The fluid constitutive equation is Carreau-like in its shear-thinning behavior but also varies with the local particle concentration. The model is compared with the experimental data gathered with nuclear magnetic resonance (NMR) imaging.

Altobelli, S.; Baer, T.; Mondy, L.; Rao, R.; Stephens, T.

1999-03-04T23:59:59.000Z

70

Adaptive h-finite element modeling of wind flow around bridges  

Science Journals Connector (OSTI)

Design of suspension bridge span is known to be very challenging, particularly considering its stability against wind flow. Traditionally, analysis of bridge section is done using wind tunnel and is very time consuming, with normal experimentation and modeling works requiring minimum 6–8 weeks. To reduce cost and time requirements of wind tunnel experiments, as an alternate approach, wind flow around bridges are investigated by application of computer modeling. One challenging aspect of computational approach is to solve the Navier–Stokes (NS) equations accurately. In the present work, automatic mesh generation technique is used to transfer the continuous fluid flow into discrete numerical data, followed by use of h-adaptive technique. The adaptive simulation is carried out using two posteriori error estimations, which are based on the velocity gradient and vorticity. The current study uses the wind flow over the Great Belt East Bridge (GBEB) as a case study.

Sanjaya K. Patro; R. Panneer Selvam; Harold Bosch

2013-01-01T23:59:59.000Z

71

Finite element analysis of controlled laser coagulation experiments  

E-Print Network (OSTI)

A mathematical model to predict the effect of laser and tissue parameters on the zone of thermal injury by laser interaction on beef liver is presented. The heat transfer and coagulation process was modeled using a non-linear finite-element model...

Tolat, Nimish Prabodh

2012-06-07T23:59:59.000Z

72

Quadrilateral/hexahedral finite element mesh coarsening  

DOE Patents (OSTI)

A technique for coarsening a finite element mesh ("FEM") is described. This technique includes identifying a coarsening region within the FEM to be coarsened. Perimeter chords running along perimeter boundaries of the coarsening region are identified. The perimeter chords are redirected to create an adaptive chord separating the coarsening region from a remainder of the FEM. The adaptive chord runs through mesh elements residing along the perimeter boundaries of the coarsening region. The adaptive chord is then extracted to coarsen the FEM.

Staten, Matthew L; Dewey, Mark W; Scott, Michael A; Benzley, Steven E

2012-10-16T23:59:59.000Z

73

Finite element analysis of substation composite insulators  

Science Journals Connector (OSTI)

Composite insulators are rapidly replacing their porcelain counterparts in electrical substation applications. These insulators consist of a glass-reinforced polymer (GRP) rod, with two metal end fittings radially crimped onto the ends of the rod during assembly. In this paper, axisymmetric finite element models are developed to evaluate the mechanical performance of composite insulators under externally applied axial compression. The analyses are performed by assuming both a perfectly bonded interface between the composite rod and the end fittings, and an imperfect interface which permits large relative sliding with Coulomb friction. Results indicate that the perfect interface model is unrealistic since it predicts singular stresses at the interface comer and an overall linear structural response. On the other hand, the imperfect interface model is found to simulate accurately the structural non-linearity caused by relative sliding of the GRP rod within the end fittings. The imperfect interface model has therefore been used to evaluate the effects of interface friction, and the extent of crimping, on the maximum load-bearing capacity of substation composite insulators.

A. Bansal; A. Schubert; M.V. Balakrishnan; M. Kumosa

1995-01-01T23:59:59.000Z

74

Rational Wachspress-type Finite Elements on Regular Hexagons  

Science Journals Connector (OSTI)

......Finite Elements on Regular Hexagons J. L. GOUT Departement de Mathematiques, Universite...Finite Elements on Regular Hexagons J. L. GOUT Departement de Mathematiques, Universite...1975) (see also Apprato, Arcangeli & Gout, 1979a, b; Gout, 1979, 1980a, b......

J. L. GOUT

75

GEO+, a finite element program on a personal computer  

E-Print Network (OSTI)

The following study is the first step toward implementation of a complete finite element analysis package on a personal computer for geotechnical engineering problems. A complete finite element analysis has been written in the C/C++ language...

Guillin, Clement Gerard

2012-06-07T23:59:59.000Z

76

Adapting a Beam-Based Rotordynamics Model to Accept a General Three-Dimensional Finite-Element Casing Model  

E-Print Network (OSTI)

-axisymmetric model, structural dynamics modes can be modeled by lateral modes in two orthogonal planes. Modal information of the complex 3D casing structures are generated, and then incorporated into the 2D code after a series of pre-processing steps. A reduction...

James, Stephen M.

2011-08-08T23:59:59.000Z

77

Dynamic finite-strain modelling of the human left ventricle in health and disease using an immersed boundary-finite element method  

Science Journals Connector (OSTI)

......grid-converged results, we use the grid spacing x = 0.156 cm for...dynamics. Advanced Computational Infrastructures for Parallel and Distributed...B. E. & Luo, X. Y. Hybrid finite difference/finite...Mesh Refinement Application Infrastructure. Available at http......

Hao Gao; David Carrick; Colin Berry; Boyce E. Griffith; Xiaoyu Luo

2014-10-01T23:59:59.000Z

78

UNIFIED FINITE ELEMENT DISCRETIZATIONS OF COUPLED DARCY-STOKES FLOW  

E-Print Network (OSTI)

by using standard Stokes elements like the MINI element or the Taylor­Hood element in the entire domain elements like the Taylor­Hood element or the MINI element for the Stokes region. The similar approach], to overcome this problem. This finite element space is defined with respect to a rectangular grid. On each

Winther, Ragnar

79

An h-Adaptive Finite-Element Technique for Constructing 3D Wind Fields  

Science Journals Connector (OSTI)

An h-adaptive, mass-consistent finite-element model (FEM) has been developed for constructing 3D wind fields over irregular terrain utilizing sparse meteorological tower data. The element size in the computational domain is dynamically controlled ...

Darrell W. Pepper; Xiuling Wang

2009-03-01T23:59:59.000Z

80

14th Finite Element Workshop --Ulm, July 2007 Finite Element Simulation  

E-Print Network (OSTI)

of Bonn, {martin.rumpf,ole.schwen}@ins.uni-bonn.de 1 #12;CT segment CFE Figure 1: The image based of the composite finite element (CFE) concept first introduced in [22, 23]. The main idea is to incorporate and corresponding geometric multigrid solvers. After a review of related methods, we explain the CFE method

Rumpf, Martin

Note: This page contains sample records for the topic "modeling finite element" 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

Finite Element Stent Design P. Mortier, M. De Beule, B. Verhegghe and P. Verdonck  

E-Print Network (OSTI)

of Drug-Eluting Stents (DES) was an enormous step forward in the treatment of narrowed arteries. Compared distribution. Numerical models (e.g. finite element models) provide a suitable tool to study and to improve stainless steel · Trifolded RAPTORTM balloon (nominal diameter 3 mm; Cordis) · Finite element code: ABAQUS

Gent, Universiteit

82

Guaranteed Verification of Finite Element Solutions of Heat Conduction  

E-Print Network (OSTI)

. . . . . . . . . . . . . . . . . . 1 1.2 Research goals . . . . . . . . . . . . . . . . . . . . . . . . . 3 1.3 Outline of the dissertation . . . . . . . . . . . . . . . . . . 4 II A POSTERIORI ERROR ESTIMATION OF A THERMAL BATTERY PROBLEM WITH HIGH ORTHOTROPY . . . . . 5 2....1 Thermal battery problem and its finite element solution . . 5 2.2 Upper and lower bounds based on residual estimators . . . 12 III ILLUSTRATION OF THE MAIN DIFFICULTY . . . . . . . . 31 3.1 Model problem with boundary layer . . . . . . . . . . . . . 31...

Wang, Delin

2012-07-16T23:59:59.000Z

83

Finite element training before real analysis: A personal view  

Science Journals Connector (OSTI)

In finite element structural analysis, we have the dilemma that an engineer can solve a very complex problem using multi-million dollar software on high-technology hardware with beautifully coloured pictures of the results, without knowing the fundamentals of the finite element method. In this paper the author presents a personal view of how this dilemma should be resolved. His solution emphasises the crucial importance of standards, quality assurance, reliability and, above all, education and training in finite element analysis.

John Robinson

1994-01-01T23:59:59.000Z

84

Wear 258 (2005) 17871793 Finite element analysis and experiments of metal/metal  

E-Print Network (OSTI)

of this simulation. © 2004 Published by Elsevier B.V. Keywords: Wear modeling; Finite element analysis 1 Published by Elsevier B.V. doi:10.1016/j.wear.2004.12.014 #12;1788 N.H. Kim et al. / Wear 258 (2005) 1787Wear 258 (2005) 1787­1793 Finite element analysis and experiments of metal/metal wear

Sawyer, Wallace

85

CharacteristicGalerkin and Mixed Finite Element Approximation of Contamination by Compressible  

E-Print Network (OSTI)

Characteristic­Galerkin and Mixed Finite Element Approximation of Contamination by Compressible­disposal contamination in porous media is modeled by a coupled system of partial differential equations for the brine, radionuclides, and heat and by a mixed finite element method for the pressure and velocity

Chou, So-Hsiang

86

A ThreeDimensional Finite Element Simulation for Transport of Nuclear Waste Contamination in Porous Media  

E-Print Network (OSTI)

A Three­Dimensional Finite Element Simulation for Transport of Nuclear Waste Contamination of South Carolina, Columbia, South Carolina ABSTRACT: Model equations for transport of nuclear­waste based up on the inherent physics. A three­dimensional finite element method for nuclear waste

Ewing, Richard E.

87

LOCKING-FREE FINITE ELEMENT METHOD FOR A BENDING MOMENT FORMULATION OF TIMOSHENKO BEAMS  

E-Print Network (OSTI)

LOCKING-FREE FINITE ELEMENT METHOD FOR A BENDING MOMENT FORMULATION OF TIMOSHENKO BEAMS FELIPE LEPE for Timo- shenko beams. It is known that standard finite elements applied to this model lead to wrong results when the thickness of the beam t is small. Here, we consider a mixed formulation in terms

Rodríguez, Rodolfo

88

Finite Element Analysis of TDR Cable-Grout-Soil Mass Interaction During Localized Shearing  

E-Print Network (OSTI)

1 Finite Element Analysis of TDR Cable-Grout-Soil Mass Interaction During Localized Shearing By J and laboratory measurement of Time Domain Reflectometry (TDR) cable-grout response to analyze the interaction between the cable, grout, and surrounding soil mass during localized shearing. Finite element (FE) model

89

Finite element simulation and parameter optimization of a flexible tactile pressure sensor array  

E-Print Network (OSTI)

A finite element model was developed to optimize design of a flexible tactile sensor. The sensor consists of layers of thin-film copper and PDMS, and the model can be used to determine the effects on sensor sensitivity and ...

Lee, Shira M. (Shira Miriam)

2005-01-01T23:59:59.000Z

90

3-D Finite Element Analyses of the Egan Cavern Field  

SciTech Connect

Three-dimensional finite element analyses were performed for the two gas-filled storage caverns at the Egan field, Jennings dome, Louisiana. The effects of cavern enlargement on surface subsidence, storage loss, and cavern stability were investigated. The finite element model simulated the leaching of caverns to 6 and 8 billion cubic feet (BCF) and examined their performance at various operating conditions. Operating pressures varied from 0.15 psi/ft to 0.9 psi/ft at the bottom of the lowest cemented casing. The analysis also examined the stability of the web or pillar of salt between the caverns under differential pressure loadings. The 50-year simulations were performed using JAC3D, a three dimensional finite element analysis code for nonlinear quasistatic solids. A damage criterion based on onset of dilatancy was used to evaluate cavern instability. Dilation results from the development of microfractures in salt and, hence, potential increases in permeability onset occurs well before large scale failure. The analyses predicted stable caverns throughout the 50-year period for the range of pressures investigated. Some localized salt damage was predicted near the bottom walls of the caverns if the caverns are operated at minimum pressure for long periods of time. Volumetric cavern closures over time due to creep were moderate to excessive depending on the salt creep properties and operating pressures. However, subsidence above the cavern field was small and should pose no problem, to surface facilities.

Klamerus, E.W.; Ehgartner, B.L.

1999-02-01T23:59:59.000Z

91

Curved finite elements by the method of initial strains  

E-Print Network (OSTI)

, pp. 383-432. 2. Clough, R. W. , "Comparison of Three Dimensional Finite Elements, " Proceedin s of the S osium on A lication of Finite Element Mhd l. t''i~Et f, Vd6'ltUt ty, 1969, pp. 1-26. 3. Stricklin, J. A. , informal proposal submitted to Dr...

Leick, Roger Dale

1974-01-01T23:59:59.000Z

92

Parallel Finite Element Simulation of Tracer Injection in Oil Reservoirs  

E-Print Network (OSTI)

Parallel Finite Element Simulation of Tracer Injection in Oil Reservoirs Alvaro L.G.A. Coutinho In this work, parallel finite element techniques for the simulation of tracer injection in oil reservoirs. Supercomputers have made it possible to consider global reservoir effects which can not be represented using

Coutinho, Alvaro L. G. A.

93

Finite element analysis of grain-matrix micro-cracking in shale within the context of a multiscale modeling  

E-Print Network (OSTI)

, hydrofracturing, or oil shale production. Current macro- scale and multiscale models do not account simultaneously

Regueiro, Richard A.

94

Rapid, automated imaging of mouse articular cartilage by microCT for early detection of osteoarthritis and finite element modelling of joint mechanics  

Science Journals Connector (OSTI)

SummaryObjective Mouse articular cartilage (AC) is mostly assessed by histopathology and its mechanics is poorly characterised. In this study: (1) we developed non-destructive imaging for quantitative assessment of AC morphology and (2) evaluated the mechanical implications of AC structural changes. Methods Knee joints obtained from naïve mice and from mice with osteoarthritis (OA) induced by destabilization of medial meniscus (DMM) for 4 and 12 weeks, were imaged by phosphotungstic acid (PTA) contrast enhanced micro-computed tomography (PTA-CT) and scored by conventional histopathology. Our software (Matlab) automatically segmented tibial AC, drew two regions centred on each tibial condyle and evaluated the volumes included. A finite element (FE) model of the whole mouse joint was implemented to evaluate AC mechanics. Results Our method achieved rapid, automated analysis of mouse AC (structural parameters in simulations estimated that AC thinning at early-stages in the DMM model (4 weeks) increases contact pressures (+39%) and Tresca stresses (+43%) in AC. Conclusion PTA-CT imaging is a fast and simple method to assess OA in murine models. Once applied more extensively to confirm its robustness, our approach will be useful for rapidly phenotyping genetically modified mice used for OA research and to improve the current understanding of mouse cartilage mechanics.

P. Das Neves Borges; A.E. Forte; T.L. Vincent; D. Dini; M. Marenzana

2014-01-01T23:59:59.000Z

95

Vocal tract changes caused by phonation into a tube: A case study using computer tomography and finite-element modeling  

Science Journals Connector (OSTI)

Phonation into a glass tube is a voice training and therapy method that leads to beneficial effects in voice production. It has not been known however what changes occur in the vocal tract during and after the phonation into a tube. This pilot study examined the vocal tract shape in a female subject before during and after phonation into a tube using computer tomography(CT). Three-dimensional finite-elementmodels (FEMs) of the vocal tract were derived from the CTimages and used to study changes in vocal tract input impedance. When phonating on vowel [a:] the data showed tightened velopharyngeal closure and enlarged cross-sectional areas of the oropharyngeal and oral cavities during and after the tube-phonation. FEM calculations revealed an increased input inertance of the vocal tract and an increased acoustic energy radiated out of the vocal tract after the tube-phonation. The results indicate that the phonation into a tube causes changes in the vocal tract which remain also when the tube is removed. These effects may help improving voice production in patients and voice professionals.

Tomáš Vampola; Anne-Maria Laukkanen; Jaromír Horá?ek; Jan G. Švec

2011-01-01T23:59:59.000Z

96

B-spline finite elements for plane elasticity problems  

E-Print Network (OSTI)

. The k-refinement is reported to be much more efficient and robust than the standard h or p- refinement used in the conventional FEM models. Besides the use of B-spline functions for structural problems, they have been used in some other fields as well... and convergence behavior. The paper reports a reduction in the numerical cost using B-spline FEM. The use of the B-spline finite element method for the thermistor problem [29,30] and for a numerical solution of Burger?s equation[31- 33] has been successfully...

Aggarwal, Bhavya

2007-04-25T23:59:59.000Z

97

Simulation of Fuel Oil System in Marine Engine Simulator Based on Finite Element Method  

Science Journals Connector (OSTI)

This paper focuses on the simulation research to fuel oil system. Hydrodynamic analysis to fuel oil system pipelines network is done and the modeling method is using finite element theory. A relative accepted ...

Diyang Li; Yuan Jiang; Boyang Li

2012-01-01T23:59:59.000Z

98

Physiological observations validate finite element models for estimating subject-specific electric field distributions induced by transcranial magnetic stimulation of the human motor cortex  

Science Journals Connector (OSTI)

Abstract Recent evidence indicates subject-specific gyral folding patterns and white matter anisotropy uniquely shape electric fields generated by TMS. Current methods for predicting the brain regions influenced by TMS involve projecting the TMS coil position or center of gravity onto realistic head models derived from structural and functional imaging data. Similarly, spherical models have been used to estimate electric field distributions generated by TMS pulses delivered from a particular coil location and position. In the present paper we inspect differences between electric field computations estimated using the finite element method (FEM) and projection-based approaches described above. We then more specifically examined an approach for estimating cortical excitation volumes based on individualistic FEM simulations of electric fields. We evaluated this approach by performing neurophysiological recordings during MR-navigated motormapping experiments. We recorded motor evoked potentials (MEPs) in response to single pulse TMS using two different coil orientations (45° and 90° to midline) at 25 different locations (5 × 5 grid, 1 cm spacing) centered on the hotspot of the right first dorsal interosseous (FDI) muscle in left motor cortex. We observed that motor excitability maps varied within and between subjects as a function of TMS coil position and orientation. For each coil position and orientation tested, simulations of the TMS-induced electric field were computed using individualistic FEM models and compared to MEP amplitudes obtained during our motormapping experiments. We found FEM simulations of electric field strength, which take into account subject-specific gyral geometry and tissue conductivity anisotropy, significantly correlated with physiologically observed MEP amplitudes (rmax = 0.91, p = 1.8 × 10-5 rmean = 0.81, p = 0.01). These observations validate the implementation of individualistic FEM models to account for variations in gyral folding patterns and tissue conductivity anisotropy, which should help improve the targeting accuracy of TMS in the mapping or modulation of human brain circuits.

Alexander Opitz; Wynn Legon; Abby Rowlands; Warren K. Bickel; Walter Paulus; William J. Tyler

2013-01-01T23:59:59.000Z

99

Accelerated finite element elastodynamic simulations using the GPU  

SciTech Connect

An approach is developed to perform explicit time domain finite element simulations of elastodynamic problems on the graphical processing unit, using Nvidia's CUDA. Of critical importance for this problem is the arrangement of nodes in memory, allowing data to be loaded efficiently and minimising communication between the independently executed blocks of threads. The initial stage of memory arrangement is partitioning the mesh; both a well established ‘greedy’ partitioner and a new, more efficient ‘aligned’ partitioner are investigated. A method is then developed to efficiently arrange the memory within each partition. The software is applied to three models from the fields of non-destructive testing, vibrations and geophysics, demonstrating a memory bandwidth of very close to the card's maximum, reflecting the bandwidth-limited nature of the algorithm. Comparison with Abaqus, a widely used commercial CPU equivalent, validated the accuracy of the results and demonstrated a speed improvement of around two orders of magnitude. A software package, Pogo, incorporating these developments, is released open source, downloadable from (http://www.pogo-fea.com/) to benefit the community. -- Highlights: •A novel memory arrangement approach is discussed for finite elements on the GPU. •The mesh is partitioned then nodes are arranged efficiently within each partition. •Models from ultrasonics, vibrations and geophysics are run. •The code is significantly faster than an equivalent commercial CPU package. •Pogo, the new software package, is released open source.

Huthwaite, Peter, E-mail: p.huthwaite@imperial.ac.uk

2014-01-15T23:59:59.000Z

100

FEHM (Finite Element Heat and Mass Transfer Code)  

NLE Websites -- All DOE Office Websites (Extended Search)

FEHM (Finite Element Heat and Mass Transfer Code) FEHM (Finite Element Heat and Mass Transfer Code) FEHM (Finite Element Heat and Mass Transfer Code) FEHM is used to simulate groundwater and contaminant flow and transport in deep and shallow, fractured and un-fractured porous media throughout the US DOE complex. June 29, 2013 software FEHM is used to simulate groundwater and contaminant flow and transport in deep and shallow, fractured and un-fractured porous media throughout the US DOE complex. Available for thumbnail of Feynman Center (505) 665-9090 Email FEHM (Finite Element Heat and Mass Transfer Code) FEHM is used to simulate groundwater and contaminant flow and transport in deep and shallow, fractured and un-fractured porous media throughout the US DOE complex. FEHM has proved to be a valuable asset on a variety of

Note: This page contains sample records for the topic "modeling finite element" 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

Finite Element Analysis of Marine Diesel Engine Crankshaft  

Science Journals Connector (OSTI)

In this paper, with the ANSYS, stress distribution and safety factor of crankshaft were analyzed by using 3D finite element method. The results show that the exposed destructive position is the transition circ...

Bin Zheng; Yongqi Liu; Ruixiang Liu…

2011-01-01T23:59:59.000Z

102

Determination of fracture toughness of AZ31 Mg alloy using the cohesive finite element method  

E-Print Network (OSTI)

Determination of fracture toughness of AZ31 Mg alloy using the cohesive finite element method X Received in revised form 21 June 2012 Accepted 11 August 2012 Keywords: Fracture toughness Cohesive finite is to develop a micromechanical approach for determining the fracture toughness. A phase-field model for grain

Chen, Long-Qing

103

A new finite element lifting surface technique  

E-Print Network (OSTI)

Element Lifting Surface Technique. (May 1973) James David Kocurek, B. S. , Texas ASM University 1 Directed by: Dr. Balusu M. Rao A numerical lifting surface technique based on discrete vortex loading elements is developed for calculating the steady..., incompress- ; ible, aerodynamic load distribution on a general, nonplanar, ideal- 1 ized body. The method, described as the "Vortex Box" technique, has been applied to general planar wings of arbitrary straight line ' geometry and to annular wings...

Kocurek, James David

2012-06-07T23:59:59.000Z

104

The Uranium Processing Facility Finite Element Meshing Discussion  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Uranium Processing Facility (UPF) Uranium Processing Facility (UPF) Finite Element Meshing Discussion ...Need picture of Building... October 25, 2011 Department of Energy - Natural Phenomenon Hazard Workshop 1 Loring Wyllie Arne Halterman Degenkolb Engineers, San Francisco Purpose of Presentation * Design vs. Analysis * Discuss the mesh criteria * Discuss the evolution of the mesh of the UPF main building model * Discuss how the mesh affects the analysis process October 25, 2011 2 Department of Energy - Natural Phenomenon Hazard Workshop FEM Modeling * GTStrudl typically used for DOE projects. * Mesh size is important * What is to be captured? * How complex is the system? * Current criteria set to capture in-plane and out-of-plane response. October 25, 2011 3

105

FINITE ELEMENT METHOD IN FLUID MECHANICS & HEAT TRANSFER  

E-Print Network (OSTI)

FINITE ELEMENT METHOD IN FLUID MECHANICS & HEAT TRANSFER AERSP-560 Department : Aerospace element techniques to especially fluid flow and heat transfer problems. A student who successfully method and write full sized application codes for analyzing fluid flow and heat transfer problems

Camci, Cengiz

106

A NONCONFORMING MIXED FINITE ELEMENT METHOD FOR ...  

E-Print Network (OSTI)

of the time-harmonic Maxwell's equations in a three-dimensional, bounded ... tric conductivity from measurements of natural electric and magnetic fields on the .... Let (?s(?) ¡s) and (?s(?) ¡s) indicate standard, complex Sobolev spaces ..... continuity constraints at the centroids of the interfaces between adjacent elements:.

1910-10-30T23:59:59.000Z

107

Three-dimensional thermo-elastic–plastic finite element modeling of quenching process of plain-carbon steel in couple with phase transformation  

Science Journals Connector (OSTI)

This study focuses on finite element investigations of quenching process which is commonly applied to improve mechanical properties such as strength, hardness, and wear/fatigue resistances, etc. During the quenching process, various kinds of microstructures evolve depending on the cooling rate and temperature variation within the steel. This microstructural evolution has a significant effect on the final dimension and geometry of the mechanical parts. In order to investigate the effect of temperature variation and phase transformation on the dimensional change and stress distribution, thermo-elastic–plastic constitutive equation coupled with the mechanical strain, thermal strain, phase transformation strain, and transformation induced plasticity is described in detail. Using the constitutive equation introduced, a finite element program was developed and used to predict distributions of the temperature, volume fraction of each phase transformed, and stress and dimensional change of the cylindrical specimen, shaft with key groove, and cam-lobe made of carbon steel. It was found out that numerically obtained values such as temperature history and stress distribution were in good agreement with the data available in the literature for the cylindrical carbon steel specimen. The developed program can be used for better understanding of mechanics involved with the quenching process.

Seong-Hoon Kang; Yong-Taek Im

2007-01-01T23:59:59.000Z

108

An AMR Capable Finite Element Diffusion Solver  

NLE Websites -- All DOE Office Websites (Extended Search)

hydrocodes have been used extensively at the National Ignition Facility (NIF) to model ignition target behavior during 1 and after the delivery of laser power 23. Over the...

109

Solar Electric Generating System II finite element analysis  

SciTech Connect

On June 2, 1992, Landers` earthquake struck the Solar Electric Generating System II, located in Daggett, California. The 30 megawatt power station, operated by the Daggett Leasing Corporation (DLC), suffered substantial damage due to structural failures in the solar farm. These failures consisted of the separation of sliding joints supporting a distribution of parabolic glass mirrors. At separation, the mirrors fell to the ground and broke. It was the desire of the DLC and the Solar Thermal Design Assistance Center (STDAC) of Sandia National Laboratories (SNL) and to redesign these joints so that, in the event of future quakes, costly breakage will be avoided. To accomplish this task, drawings of collector components were developed by the STDAC, from which a detailed finite element computer model of a solar collector was produced. This nonlinear dynamic model, which consisted of over 8,560 degrees of freedom, underwent model reduction to form a low order nonlinear dynamic model containing only 40 degrees of freedom. This model was then used as a design tool to estimate joint dynamics. Using this design tool, joint configurations were modified, and an acceptable joint redesign determined. The results of this analysis showed that the implementation of metal stops welded to support shafts for the purpose of preventing joint separation is a suitable joint redesign. Moreover, it was found that, for quakes of Landers` magnitude, mirror breakage due to enhanced vibration in the trough assembly is unlikely.

Dohner, J.L.; Anderson, J.R.

1994-04-01T23:59:59.000Z

110

Hierarchical strategy for rapid finite element analysis  

E-Print Network (OSTI)

that is being researched quite extensively due to its high strength and stiffness. But it is hard to model because other phenomena like quantum mechanics come into play in the nano-scale and conventional continuum mechanics is not valid at such scales. So... that is being researched quite extensively due to its high strength and stiffness. But it is hard to model because other phenomena like quantum mechanics come into play in the nano-scale and conventional continuum mechanics is not valid at such scales. So...

Varghese, Julian

2004-09-30T23:59:59.000Z

111

Modified Mini finite element for the Stokes problem in ?2 or ?3  

Science Journals Connector (OSTI)

We analyze a modified version of the Mini finite element (or the Mini* finite element) for the Stokes problem...2 or ?3. The cross?grid element of order one in ?3 is also analyzed. The stability is verified with ...

Yongdeok Kim; Sungyun Lee

112

Finite element decomposition of the human neocortex  

E-Print Network (OSTI)

. . . . . . . . . . . . . . . . . . . . . ?. .. . , . . . . . C. Application of Software Tools to the Human Neocortex. . . . . . . . 72 . . . . 72 . . . . 74 VIII RESULTS. . . . . 77 A. B. C. D. E. F. Contour Extraction . , Solid Model Reconstruction of the Right Hemisphere. . . . Extraction.... Summary. B. Future Work. . . . . . 101 . . . . . 101 REFERENCES. , . . . . . 105 . . . . . 110 LIST OF FIGURES FIGURE Page 1 Reconstruction stages. . . . . . 2 Voronoi diagram and Delaunay triangulation . . . . . 13 3 IVS and EVS of two contours...

Chow, Seeling

2012-06-07T23:59:59.000Z

113

Dennis, Eberhart, Dulikravich & Radons FINITE ELEMENT SIMULATION OF COOLING  

E-Print Network (OSTI)

). The simulations performed in this study consider ice packs applied to head and neck as well as using a head-cooling1 Dennis, Eberhart, Dulikravich & Radons FINITE ELEMENT SIMULATION OF COOLING OF REALISTIC 3-D Rapid cooling of the brain in the first minutes following the onset of cerebral ischemia

Dennis, Brian

114

AN ADAPTIVE SURFACE FINITE ELEMENT METHOD BASED ON VOLUME MESHES  

E-Print Network (OSTI)

makes use of a (standard) outer volume mesh to discretize an equation on a two-dimensional surface, interface, finite element, level set method, adaptivity, error estimator AMS subject classification. 65N15 measure The first author was partially supported by National Science Foundation grant DMS-1016094

Demlow, Alan

115

Finite Element Discretization Strategies for the Inverse Electrocardiographic (ECG) Problem  

E-Print Network (OSTI)

Finite Element Discretization Strategies for the Inverse Electrocardiographic (ECG) Problem Dafang electrocardiographic (ECG) problems re- quires the ability to both quantify and minimize approxi- mation errors specifically for the inverse ECG prob- lem. By quantitatively analyzing the connection between the ill

Utah, University of

116

Periodic Boundary Conditions in the ALEGRA Finite Element Code  

SciTech Connect

This document describes the implementation of periodic boundary conditions in the ALEGRA finite element code. ALEGRA is an arbitrary Lagrangian-Eulerian multi-physics code with both explicit and implicit numerical algorithms. The periodic boundary implementation requires a consistent set of boundary input sets which are used to describe virtual periodic regions. The implementation is noninvasive to the majority of the ALEGRA coding and is based on the distributed memory parallel framework in ALEGRA. The technique involves extending the ghost element concept for interprocessor boundary communications in ALEGRA to additionally support on- and off-processor periodic boundary communications. The user interface, algorithmic details and sample computations are given.

AIDUN,JOHN B.; ROBINSON,ALLEN C.; WEATHERBY,JOE R.

1999-11-01T23:59:59.000Z

117

A finite element method for low-speed compressible flows.  

SciTech Connect

The derivation and justification for various low-speed approximations to the fully compressible, Navier-Stokes equations are presented. A numerical formulation based on the finite element method is developed and implemented as an extension to the standard Boussinesq equations. Example steady and transient flow problems are simulated to examine the performance of the numerical algorithm and the solution differences with the more commonly studied Boussinesq approximation.

Martinez, Mario J.; Gartling, David K.

2003-04-01T23:59:59.000Z

118

Piezoelectric theory for finite element analysis of ultrasonic motors  

SciTech Connect

The authors present the fundamental equations of piezoelectricity and references. They show how a second form of the equations and a second set of coefficients can be found, through inversions involving the elasticity tensor. They show how to compute the clamped permittivity matrix from the unclamped matrix. The authors list the program pzansys.ftn and present examples of its use. This program does the conversions and calculations needed by the finite element program ANSYS.

Emery, J.D.; Mentesana, C.P.

1997-06-01T23:59:59.000Z

119

Implementation of finite element analysis into the athletic shoe design process  

E-Print Network (OSTI)

Finite element analysis is used by companies throughout the world as a substitution for manually testing prototypes. With the assistance of finite element analysis many companies and industries have decreased the time and ...

Hidalgo, Maria E. (Maria Estela), 1982-

2004-01-01T23:59:59.000Z

120

Modeling of underwater noise from pile driving using coupled finite element and parabolic equation model with improved parabolic equation starting field  

Science Journals Connector (OSTI)

An offshore wind farm will be constructed in the Yellow Sea west of Korean Peninsula where there are extensive fishing activity and numerous fishery farms. To study the effect of underwater piling noise on fishing and marine lives we model the pile driving noise propagation using coupled FE and PE model. The near-field noise is computed by FE model considering detailed specifications of the pile driving system. We apply 2D axis-symmetric geometry and utilize acoustic structure interaction analysis in the frequency domain. The FE results are used to compose the starting field for PE model where appropriate range selection is an important factor to cover most of the contributing ray paths. Extrapolation technique to compensate the lack of FE data and the numerical filtering method to smooth the FE result are discussed. In the far-field the noise propagation is modeled by the split step Pade PE algorithm. The improved PE starting field seems to give refined result than previous coupled model.

Jungyong Park

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling finite element" 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

Solving multidimensional reactive flow problems with adaptive finite elements  

E-Print Network (OSTI)

developments in the design and implementation of finite el- ement methods for the compressible Navier. Braack and T. Richter enthalpy, k its molar production rate, and Fk its mass diffusion flux not the most accurate diffusion model. For hydrogen flames, for instance, multicomponent diffusion models

Richter, Thomas

122

SIMULATION OF RADIO-FREQUENCY ABLATION USING COMPOSITE FINITE ELEMENT METHODS  

E-Print Network (OSTI)

with Composite-Finite- Element (CFE) methods2 . CFE methods are characterized by the capa- bility of resolving

Preusser, Tobias

123

NORTHWESTERN UNIVERSITY Finite Element Analysis of TDR Cable-Grout-Soil Mass  

E-Print Network (OSTI)

NORTHWESTERN UNIVERSITY Finite Element Analysis of TDR Cable-Grout-Soil Mass Interaction During Cable Shear Test.................................................................................................................... 9 Cable Types

124

BLT-EC (Breach, Leach Transport, and Equilibrium Chemistry), a finite-element model for assessing the release of radionuclides from low-level waste disposal units: Background, theory, and model description  

SciTech Connect

Performance assessment models typically account for the processes of sorption and dissolution-precipitation by using an empirical distribution coefficient, commonly referred to as K{sub d} that combines the effects of all chemical reactions between solid and aqueous phases. In recent years, however, there has been an increasing awareness that performance assessments based solely on empirically based K{sub d} models may be incomplete, particularly for applications involving radionuclides having sorption and solubility properties that are sensitive to variations in the in-situ chemical environment. To accommodate variations in the in-situ chemical environment, and to assess its impact on radionuclide mobility, it is necessary to model radionuclide release, transport, and chemical processes in a coupled fashion. This modeling has been done and incorporated into the two-dimensional, finite-element, computer code BLT-EC (Breach, Leach, Transport, Equilibrium Chemistry). BLT-EC is capable of predicting container degradation, waste-form leaching, and advective-dispersive, multispecies, solute transport. BLT-EC accounts for retardation directly by modeling the chemical processes of complexation, sorption, dissolution-precipitation, ion-exchange, and oxidation-reduction reactions. In this report we: (1) present a detailed description of the various physical and chemical processes that control the release and migration of radionuclides from shallow land LLW disposal facilities; (2) formulate the mathematical models that represent these processes; (3) outline how these models are incorporated and implemented in BLT-EC; and (4) demonstrate the application of BLT-EC on a set of example problems.

MacKinnon, R.J.; Sullivan, T.M. [Brookhaven National Lab., Upton, NY (United States); Simonson, S.A. [Massachusetts Inst. of Technology, Cambridge, MA (United States); Suen, C.J. [California State Univ., Fresno, CA (United States)

1995-08-01T23:59:59.000Z

125

Analysis of anelastic flow and numerical treatment via finite elements  

SciTech Connect

In this report, we reconsider the various approximations made to the full equations of motion and energy transport for treating low-speed flows with significant temperature induced property variations. This entails assessment of the development of so-called anelastic for low-Mach number flows outside the range of validity of the Boussinesq equations. An integral part of this assessment is the development of a finite element-based numerical scheme for obtaining approximate numerical solutions to this class of problems. Several formulations were attempted and are compared.

Martinez, M.J.

1994-05-01T23:59:59.000Z

126

Finite volume stochastic Ising model .##+$ & ## ## (3# )  

E-Print Network (OSTI)

Finite volume stochastic Ising model .##+$ & ## ## (3# ) ## (%s+.##(j# Ising model /##;.B'K.?'B#B#%#*B..1$' Jx AE.#oe/#+70#)h.U4Rf$* t# Ising model .##;RxB'K+b# O Markov ## R#,&# K#oefi#S+#OL& K*J#+#`O finite volume stochastic Ising model /c

Yoshida, Nobuo

127

mFES: A Robust Molecular Finite Element Solver for Electrostatic Energy Computations  

Science Journals Connector (OSTI)

We present a robust method for the calculation of electrostatic potentials of large molecular systems using tetrahedral finite elements (FE). Compared to the finite difference (FD) method using a regular simple cubic grid to solve the Poisson equation, ...

I. Sakalli; J. Schöberl; E. W. Knapp

2014-10-09T23:59:59.000Z

128

THE FINITE GROUPS WITH NO REAL p-ELEMENTS SILVIO DOLFI, GUNTER MALLE, AND GABRIEL NAVARRO  

E-Print Network (OSTI)

THE FINITE GROUPS WITH NO REAL p-ELEMENTS SILVIO DOLFI, GUNTER MALLE, AND GABRIEL NAVARRO Abstract/Generalitat Valenciana. 1 #12;2 SILVIO DOLFI, GUNTER MALLE, AND GABRIEL NAVARRO Theorem D. Let G be a finite group

Malle, Gunter

129

FINITE ELEMENT ANALYSIS OF BULK TRITIUM SHIPPING PACKAGE  

SciTech Connect

The Bulk Tritium Shipping Package was designed by Savannah River National Laboratory. This package will be used to transport tritium. As part of the requirements for certification, the package must be shown to meet the scenarios of the Hypothetical Accident Conditions (HAC) defined in Code of Federal Regulations Title 10 Part 71 (10CFR71). The conditions include a sequential 30-foot drop event, 30-foot dynamic crush event, and a 40-inch puncture event. Finite Element analyses were performed to support and expand upon prototype testing. Cases similar to the tests were evaluated. Additional temperatures and orientations were also examined to determine their impact on the results. The peak stress on the package was shown to be acceptable. In addition, the strain on the outer drum as well as the inner containment boundary was shown to be acceptable. In conjunction with the prototype tests, the package was shown to meet its confinement requirements.

Jordan, J.

2010-06-02T23:59:59.000Z

130

Finite element structural study of the VGOT wind turbine  

Science Journals Connector (OSTI)

We analyse the implementation of the finite element method to simulate the structural behaviour of the blade-wagons of variable-geometry oval-trajectory (VGOT) Darrieus wind turbines. The key feature of a VGOT machine is that each blade, instead of rotating around a central vertical axis, slides over rails mounted on a wagon formed by a tubular reticulated structure supported by standard train bogies. The structure should be designed to absorb the efforts in the vertical and traverse directions of the railroad due to the aerodynamic loads, the weight of the components and the centrifugal acceleration along the curved tracks. We show some results for the tip deflection and the tip torsion of the blade, the frontal and lateral angle variations in the blade bottom and the Von Misses tensions of five sample beams, all of them in function of the trajectory-length parameter; and some examples of the deformed configuration of the reticulated structure.

Alejandro D. Otero; Fernando L. Ponta

2004-01-01T23:59:59.000Z

132

Transient finite element analysis of electric double layer using Nernst-Planck-Poisson equations with a modified stern layer  

E-Print Network (OSTI)

Finite element analysis of electric double layer capacitors using a transient nonlinear Nernst-Planck-Poisson (NPP) model and Nernst-Planck-Poisson-modified Stern layer (NPPMS) model are presented in 1D and 2D. The NPP model provided unrealistic ion...

Lim, Jong Il

2007-04-25T23:59:59.000Z

133

TESLA FEL Report 200602 Finite Element Analyses for RF Photoinjector Gun Cavities  

E-Print Network (OSTI)

TESLA FEL Report 200602 Finite Element Analyses for RF Photoinjector Gun ..............................................................................................................................................................19 3.1. DESY GUN 2..................................................................................................................................................19 3.2. DESY GUN 4

134

Evaluation of Finite Element Method Based Software for Simulation of Hydropower Generator - Power Grid Interaction.  

E-Print Network (OSTI)

?? The accuracy, ease of use, and execution time of the finite element method based software Maxwell coupled to the system simulation software Simplorer was… (more)

Persarvet, Gustav

2011-01-01T23:59:59.000Z

135

Hypersonic heat transfer and anisotropic visualization with a higher order discontinuous Galerkin finite element method .  

E-Print Network (OSTI)

??Higher order discretizations of the Navier-Stokes equations promise greater accuracy than conventional computational aerodynamics methods. In particular, the discontinuous Galerkin (DG) finite element method has… (more)

Quattrochi, Douglas J. (Douglas John)

2006-01-01T23:59:59.000Z

136

E-Print Network 3.0 - advanced finite element Sample Search Results  

NLE Websites -- All DOE Office Websites (Extended Search)

Institute and Department of Mathematics Summary: .T. Williams, and E. Woodward 1982. Recent advances in the Galerkin finite-element method as applied... A review of...

137

Simulation of the ultrasonic array response from real branched cracks using an efficient finite element method  

SciTech Connect

A hybrid model to simulate the ultrasonic array response from stress corrosion cracks is presented. These cracks are branched and difficult to detect so the model is required to enable optimization of an array design. An efficient frequency-domain finite element method is described and selected to simulate the ultrasonic scattering. Experimental validation results are presented, followed by an example of the simulated ultrasonic array response from a real stress corrosion crack whose geometry is obtained from an X-ray Computed Tomography image. A simulation-assisted array design methodology, which includes the model and use of real crack geometries, is proposed.

Felice, Maria V. [Department of Mechanical Engineering, University of Bristol, Bristol BS8 1TR, United Kingdom and Rolls-Royce plc., Bristol BS34 7QE (United Kingdom); Velichko, Alexander; Wilcox, Paul D. [Department of Mechanical Engineering, University of Bristol, Bristol BS8 1TR (United Kingdom); Barden, Tim J.; Dunhill, Tony K. [Rolls-Royce plc., Bristol BS34 7QE (United Kingdom)

2014-02-18T23:59:59.000Z

138

An h-adaptive finite element method for turbulent heat transfer  

SciTech Connect

A two-equation turbulence closure model (k-{omega}) using an h-adaptive grid technique and finite element method (FEM) has been developed to simulate low Mach flow and heat transfer. These flows are applicable to many flows in engineering and environmental sciences. Of particular interest in the engineering modeling areas are: combustion, solidification, and heat exchanger design. Flows for indoor air quality modeling and atmospheric pollution transport are typical types of environmental flows modeled with this method. The numerical method is based on a hybrid finite element model using an equal-order projection process. The model includes thermal and species transport, localized mesh refinement (h-adaptive) and Petrov-Galerkin weighting for the stabilizing the advection. This work develops the continuum model of a two-equation turbulence closure method. The fractional step solution method is stated along with the h-adaptive grid method (Carrington and Pepper, 2002). Solutions are presented for 2d flow over a backward-facing step.

Carriington, David B [Los Alamos National Laboratory

2009-01-01T23:59:59.000Z

139

Beyond first-order finite element schemes in micromagnetics  

SciTech Connect

Magnetization dynamics in ferromagnetic materials is ruled by the Landau–Lifshitz–Gilbert equation (LLG). Reliable schemes must conserve the magnetization norm, which is a nonconvex constraint, and be energy-decreasing unless there is pumping. Some of the authors previously devised a convergent finite element scheme that, by choice of an appropriate test space – the tangent plane to the magnetization – reduces to a linear problem at each time step. The scheme was however first-order in time. We claim it is not an intrinsic limitation, and the same approach can lead to efficient micromagnetic simulation. We show how the scheme order can be increased, and the nonlocal (magnetostatic) interactions be tackled in logarithmic time, by the fast multipole method or the non-uniform fast Fourier transform. Our implementation is called feeLLGood. A test-case of the National Institute of Standards and Technology is presented, then another one relevant to spin-transfer effects (the spin-torque oscillator)

Kritsikis, E., E-mail: kritsikis@math.univ-paris13.fr [Laboratoire d'analyse, géométrie et applications, université Paris 13, CNRS UMR 7539, 93430 Villetaneuse (France); Vaysset, A.; Buda-Prejbeanu, L.D. [SPINTEC, INAC, UMR CEA/CNRS/UJF-Grenoble 1/Grenoble-INP, F-38054 Grenoble (France)] [SPINTEC, INAC, UMR CEA/CNRS/UJF-Grenoble 1/Grenoble-INP, F-38054 Grenoble (France); Alouges, F. [CMAP, CNRS and École polytechnique, F-91128 Palaiseau (France)] [CMAP, CNRS and École polytechnique, F-91128 Palaiseau (France); Toussaint, J.-C. [Institut Néel, CNRS and université Joseph Fourier, F-38042 Grenoble (France)] [Institut Néel, CNRS and université Joseph Fourier, F-38042 Grenoble (France)

2014-01-01T23:59:59.000Z

140

A finite element approach to the 3D CSEM modeling problem and applications to the study of the effect of target interaction andtopography  

E-Print Network (OSTI)

to the dissipation of charge accumulated on the conductor boundary. The e?ect of this interaction varies with host conductivity, transmitter frequency, and conductor geometry, orientation, and conductivity. For three test models containingtwo highly conductive...

Stalnaker, Jack Lee

2005-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling finite element" 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

Using a 3D finite element forward modeling code to analyze resistive structures with controlled-source electromagnetics in a marine environment  

E-Print Network (OSTI)

to simulate CSEM experiments. The objective of the present study is to model the changes in electromagnetic response for a resistive disk and a more geometrically complex structure, which are rough approximations of hydrocarbon reservoirs. The parameters...

King, Joshua David

2005-02-17T23:59:59.000Z

142

Finite element simulations of hydrodynamic trapping in microfluidic particle-trap array systems  

E-Print Network (OSTI)

Finite element simulations of hydrodynamic trapping in microfluidic particle- trap array systems;Finite element simulations of hydrodynamic trapping in microfluidic particle-trap array systems Xiaoxiao) simulation is a powerful tool in the design and implementation of microfluidic systems, especially

Nehorai, Arye

143

On Smoothing Surfaces in Voxel Based Finite Element Analysis of Trabecular Bone  

E-Print Network (OSTI)

-)finite element analysis based on three-dimen- sional computed tomography (CT) data of human bone takes place finite element (FE) analysis. The approach based on the FE analysis leads to linear systems of equations analysis the computational domain is composed of a multitude of tiny cubes, so-called voxels

Frey, Pascal

144

Finite element solutions of heat transfer in molten polymer flow in tubes with viscous dissipation  

E-Print Network (OSTI)

Finite element solutions of heat transfer in molten polymer flow in tubes with viscous dissipation the results of finite element analysis of a heat transfer problem of flowing polymer melts in a tube­Nusselt problem 1. Introduction Heat transfer to incompressible viscous non-Newto- nian fluids is a problem

Wei, Dongming

145

FINITE-ELEMENT FORMULATIONS FOR PROBLEMS OF LARGE ELASTIC-PLASTIC DEFORMATION  

E-Print Network (OSTI)

FINITE-ELEMENT FORMULATIONS FOR PROBLEMS OF LARGE ELASTIC-PLASTIC DEFORMATION R. M. MCM~EKING and J elastic-plastic flow.The method is based on Hill's variational principle for incremental deformations in a manner which allows any conventions finite element program, for "small strain" elastic-plastic analysis

146

Measurement and finite element analysis of temperature distribution in arc welding process  

Science Journals Connector (OSTI)

This presentation describes both the experimental measurement and finite element analysis used to study the temperature distribution during a metal inert gas (MIG) welding process, including the cooling down period. Welding was carried out on ... Keywords: FEA, MIG welding, arc welding, cracking, finite element analysis, metal inert gas welding, residual stress, simulation, temperature distribution, weldment temperature

C. K. Lee; J. Candy; C. P. H. Tan

2004-12-01T23:59:59.000Z

147

Multiscale finite element analysis of elastic wave scattering from localized defects  

Science Journals Connector (OSTI)

This paper investigates the use of a multiscale finite element approach to study the interaction between elastic waves and localized defects. The analysis of wave-defect interaction is of fundamental importance for the development of ultrasonic non-destructive ... Keywords: Elastic wave scattering, Finite element method, Multiscale analysis

F. Casadei, J. J. Rimoli, M. Ruzzene

2014-10-01T23:59:59.000Z

148

Finite element meshing approached as a global minimization process  

SciTech Connect

The ability to generate a suitable finite element mesh in an automatic fashion is becoming the key to being able to automate the entire engineering analysis process. However, placing an all-hexahedron mesh in a general three-dimensional body continues to be an elusive goal. The approach investigated in this research is fundamentally different from any other that is known of by the authors. A physical analogy viewpoint is used to formulate the actual meshing problem which constructs a global mathematical description of the problem. The analogy used was that of minimizing the electrical potential of a system charged particles within a charged domain. The particles in the presented analogy represent duals to mesh elements (i.e., quads or hexes). Particle movement is governed by a mathematical functional which accounts for inter-particles repulsive, attractive and alignment forces. This functional is minimized to find the optimal location and orientation of each particle. After the particles are connected a mesh can be easily resolved. The mathematical description for this problem is as easy to formulate in three-dimensions as it is in two- or one-dimensions. The meshing algorithm was developed within CoMeT. It can solve the two-dimensional meshing problem for convex and concave geometries in a purely automated fashion. Investigation of the robustness of the technique has shown a success rate of approximately 99% for the two-dimensional geometries tested. Run times to mesh a 100 element complex geometry were typically in the 10 minute range. Efficiency of the technique is still an issue that needs to be addressed. Performance is an issue that is critical for most engineers generating meshes. It was not for this project. The primary focus of this work was to investigate and evaluate a meshing algorithm/philosophy with efficiency issues being secondary. The algorithm was also extended to mesh three-dimensional geometries. Unfortunately, only simple geometries were tested before this project ended. The primary complexity in the extension was in the connectivity problem formulation. Defining all of the interparticle interactions that occur in three-dimensions and expressing them in mathematical relationships is very difficult.

WITKOWSKI,WALTER R.; JUNG,JOSEPH; DOHRMANN,CLARK R.; LEUNG,VITUS J.

2000-03-01T23:59:59.000Z

149

An implementation analysis of the linear discontinuous finite element method  

SciTech Connect

This paper provides an implementation analysis of the linear discontinuous finite element method (LD-FEM) that spans the space of (l, x, y, z). A practical implementation of LD includes 1) selecting a computationally efficient algorithm to solve the 4 x 4 matrix system Ax = b that describes the angular flux in a mesh element, and 2) choosing how to store the data used to construct the matrix A and the vector b to either reduce memory consumption or increase computational speed. To analyze the first of these, three algorithms were selected to solve the 4 x 4 matrix equation: Cramer's rule, a streamlined implementation of Gaussian elimination, and LAPACK's Gaussian elimination subroutine dgesv. The results indicate that Cramer's rule and the streamlined Gaussian elimination algorithm perform nearly equivalently and outperform LAPACK's implementation of Gaussian elimination by a factor of 2. To analyze the second implementation detail, three formulations of the discretized LD-FEM equations were provided for implementation in a transport solver: 1) a low-memory formulation, which relies heavily on 'on-the-fly' calculations and less on the storage of pre-computed data, 2) a high-memory formulation, which pre-computes much of the data used to construct A and b, and 3) a reduced-memory formulation, which lies between the low - and high-memory formulations. These three formulations were assessed in the Jaguar transport solver based on relative memory footprint and computational speed for increasing mesh size and quadrature order. The results indicated that the memory savings of the low-memory formulation were not sufficient to warrant its implementation. The high-memory formulation resulted in a significant speed advantage over the reduced-memory option (10-50%), but also resulted in a proportional increase in memory consumption (5-45%) for increasing quadrature order and mesh count; therefore, the practitioner should weigh the system memory constraints against any required runtime constraints to determine which option is more suitable for his or her specific applications. (authors)

Becker, T. L. [Bechtel Marine Propulsion Corporation, Knolls Atomic Power Laboratory, P.O. Box 1072, Schenectady, NY 12301-1072 (United States)

2013-07-01T23:59:59.000Z

150

Finite-element/progressive-lattice-sampling response surface methodology and application to benchmark probability quantification problems  

SciTech Connect

Optimal response surface construction is being investigated as part of Sandia discretionary (LDRD) research into Analytic Nondeterministic Methods. The goal is to achieve an adequate representation of system behavior over the relevant parameter space of a problem with a minimum of computational and user effort. This is important in global optimization and in estimation of system probabilistic response, which are both made more viable by replacing large complex computer models with fast-running accurate and noiseless approximations. A Finite Element/Lattice Sampling (FE/LS) methodology for constructing progressively refined finite element response surfaces that reuse previous generations of samples is described here. Similar finite element implementations can be extended to N-dimensional problems and/or random fields and applied to other types of structured sampling paradigms, such as classical experimental design and Gauss, Lobatto, and Patterson sampling. Here the FE/LS model is applied in a ``decoupled`` Monte Carlo analysis of two sets of probability quantification test problems. The analytic test problems, spanning a large range of probabilities and very demanding failure region geometries, constitute a good testbed for comparing the performance of various nondeterministic analysis methods. In results here, FE/LS decoupled Monte Carlo analysis required orders of magnitude less computer time than direct Monte Carlo analysis, with no appreciable loss of accuracy. Thus, when arriving at probabilities or distributions by Monte Carlo, it appears to be more efficient to expend computer-model function evaluations on building a FE/LS response surface than to expend them in direct Monte Carlo sampling.

Romero, V.J.; Bankston, S.D.

1998-03-01T23:59:59.000Z

151

An explicit finite element formulation for dynamic strain localization and damage evolution in metals  

SciTech Connect

An explicit finite element formulation, used to study the behavior and failure mechanisms of metallic materials under high strain rate loading, is presented. The formulation is based on the assumed-strain approach of Fish and Belytschko [1988], which allows localization bands to be embedded within an element, thereby alleviating mesh sensitivity and reducing the required computational effort. The behavior of the material outside localization bands (and of the virgin material prior to the onset of strain localization) is represented using a Gurson-type coupled plasticity-damage model based on the work of Johnson and Addessio [1988]. Assuming adiabatic conditions, the response of the localization band material is represented by a set of constitutive equations for large elasticviscoplastic deformations in metals at high strain rates and high homologous temperatures (see Brown et al. [1989]). Computational results are compared to experimental data for different metallic alloys to illustrate the advantages of the proposed modeling strategy.

Mourad, Hashem M [Los Alamos National Laboratory; Bronkhorst, Curt A [Los Alamos National Laboratory; Addessio, Francis L [Los Alamos National Laboratory

2010-12-16T23:59:59.000Z

152

Higher-order adaptive finite-element methods for Kohn–Sham density functional theory  

SciTech Connect

We present an efficient computational approach to perform real-space electronic structure calculations using an adaptive higher-order finite-element discretization of Kohn–Sham density-functional theory (DFT). To this end, we develop an a priori mesh-adaption technique to construct a close to optimal finite-element discretization of the problem. We further propose an efficient solution strategy for solving the discrete eigenvalue problem by using spectral finite-elements in conjunction with Gauss–Lobatto quadrature, and a Chebyshev acceleration technique for computing the occupied eigenspace. The proposed approach has been observed to provide a staggering 100–200-fold computational advantage over the solution of a generalized eigenvalue problem. Using the proposed solution procedure, we investigate the computational efficiency afforded by higher-order finite-element discretizations of the Kohn–Sham DFT problem. Our studies suggest that staggering computational savings—of the order of 1000-fold—relative to linear finite-elements can be realized, for both all-electron and local pseudopotential calculations, by using higher-order finite-element discretizations. On all the benchmark systems studied, we observe diminishing returns in computational savings beyond the sixth-order for accuracies commensurate with chemical accuracy, suggesting that the hexic spectral-element may be an optimal choice for the finite-element discretization of the Kohn–Sham DFT problem. A comparative study of the computational efficiency of the proposed higher-order finite-element discretizations suggests that the performance of finite-element basis is competing with the plane-wave discretization for non-periodic local pseudopotential calculations, and compares to the Gaussian basis for all-electron calculations to within an order of magnitude. Further, we demonstrate the capability of the proposed approach to compute the electronic structure of a metallic system containing 1688 atoms using modest computational resources, and good scalability of the present implementation up to 192 processors.

Motamarri, P. [Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI 48109 (United States)] [Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI 48109 (United States); Nowak, M.R. [Department of Electrical Engineering, University of Michigan, Ann Arbor, MI 48109 (United States)] [Department of Electrical Engineering, University of Michigan, Ann Arbor, MI 48109 (United States); Leiter, K.; Knap, J. [U.S. Army Research Labs, Aberdeen Proving Ground, Aberdeen, MD 21001 (United States)] [U.S. Army Research Labs, Aberdeen Proving Ground, Aberdeen, MD 21001 (United States); Gavini, V., E-mail: vikramg@umich.edu [Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI 48109 (United States)

2013-11-15T23:59:59.000Z

153

Adaptive strategies using standard and mixed finite elements for wind field adjustment  

SciTech Connect

In order to find a map of wind velocities, this study tries to obtain an incompressible wind field that adjusts to an experimental one: also verifying the corresponding boundary conditions of physical interest. This problem has been solved by several authors using finite differences or standard finite element techniques. In this paper, this problem is solved by two different adaptive finite element methods. The first makes use of standard finite element techniques, using linear interpolation of a potential function. In the second, a direct computation of the velocity field is undertaken by means of a mixed finite element method. Several error indicators are proposed for both formulations together with an adaptive strategy. We have applied both methods to several typical test problems, as well as to realistic data corresponding to the Island of Fuerteventura, with satisfactory results from a numerical point of view. 13 refs., 16 figs., 1 tab.

Winter, G.; Montero, G.; Montenegro, R. [Univ. of Las Palmas de Gran Canaria, FL (United States)] [Univ. of Las Palmas de Gran Canaria, FL (United States)

1995-01-01T23:59:59.000Z

154

Numerical simulation of borehole acoustic logging in the frequency and time domains with hp-adaptive finite elements  

E-Print Network (OSTI)

Numerical simulation of borehole acoustic logging in the frequency and time domains with hp elasticity Coupled problems hp-adaptive finite elements a b s t r a c t Accurate numerical simulation physical modeling combined with accurate and efficient numerical dis- cretization and solution techniques

Torres-Verdín, Carlos

155

Nonlinear structural finite element analysis using the preconditioned Lanczos method on serial and parallel computers  

Science Journals Connector (OSTI)

The application of the Lanczos algorithm in Newton-like methods for solving non-linear systems of equations arising in nonlinear structural finite element analysis is presented. It is shown that with appropria...

Th. Rottner; I. Lenhardt; G. Alefeld; K. Schweizerhof

1997-09-01T23:59:59.000Z

156

Hypersonic heat transfer and anisotropic visualization with a higher order discontinuous Galerkin finite element method  

E-Print Network (OSTI)

Higher order discretizations of the Navier-Stokes equations promise greater accuracy than conventional computational aerodynamics methods. In particular, the discontinuous Galerkin (DG) finite element method has O(hP+l) ...

Quattrochi, Douglas J. (Douglas John)

2006-01-01T23:59:59.000Z

157

Algebraic multigrid for stabilized finite element discretizations of the Navier Stokes equation  

E-Print Network (OSTI)

A multilevel method for the solution of systems of equations generated by stabilized Finite Element discretizations of the Euler and Navier Stokes equations on generalized unstructured grids is described. The method is ...

Okusanya, Tolulope Olawale, 1972 -

2002-01-01T23:59:59.000Z

158

Finite Element Analysis of Ballistic Penetration of Plain Weave Twaron CT709® Fabrics: A Parametric Study  

E-Print Network (OSTI)

The ballistic impact of Twaron CT709® plain weave fabrics is studied using an explicit finite element method. Many existing approximations pertaining to woven fabrics cannot adequately represent strain rate-dependent behavior exhibited by the Twaron...

Gogineni, Sireesha

2011-10-21T23:59:59.000Z

159

Finite element analysis of flows in secondary settling tanks D. Kleine 1 B. D. Reddy 2  

E-Print Network (OSTI)

Finite element analysis of flows in secondary settling tanks D. Kleine 1 B. D. Reddy 2 December 7, 2003 Abstract The equations governing unsteady flows in secondary settling tanks, a component settling tanks, and against results obtained from a finite difference code based on an idealized one

Reddy, Batmanathan Dayanand "Daya"

160

A finite element viscous flow analysis in a radial turbine scroll  

E-Print Network (OSTI)

1987 Major Subject: Mechanical Engineering A FINITE ELEMENT VISCOUS FLOW ANALYSIS IN A RADIAL TURBINE SCROLL A Thesis by DONALD LEE HILL JR. Approved as to style snd content by: Dr. Erian A. Baskharone (Chairman of Conunittee) Dr. Alan B azzolo...A FINITE ELEMENT VISCOUS FLOW ANALYSIS IN A RADIAL TURBINE SCROLL A Thesis DONALD LEE HILL JR. Submitted to the Graduate College. of Texas ASM University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE December...

Hill, Donald Lee

1987-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling finite element" 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

Finite element analysis of conjugate heat transfer in axisymmetric pipe flows  

E-Print Network (OSTI)

FINITE ELEMENT ANALYSIS OF CONJUGATE HEAT TRANSFER IN AXISYMMETRIC PIPE FLOWS A Thesis by ROBERT MILLER FITHEN Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MA STER... OF S CI EN CE August 1987 Major Subject: Mechanical Engineering FINITE ELEMENT ANALYSIS OF CONJUGATE HEAT TRANSFER IN AXISYMMETRIC PIPE FLOWS A Thesis by ROBERT MILLER FITHEN Approved ss to style and content by: N. K. Anand (Chairman of Committee...

Fithen, Robert Miller

2012-06-07T23:59:59.000Z

162

Approximation of vector fields using discrete div-rot variational splines in a finite element space  

Science Journals Connector (OSTI)

This paper deals with an approximation problem concerning vector fields through the new notion of div-rot variational splines. The minimizing problem is addressed in a finite element space through the choice of some semi-norms based on decomposition ... Keywords: 65D05, 65D07, 65D10, 65D17, Approximation of vector fields, Discrete problem, Finite element, Smoothing, Spline, Variational method

A. Kouibia; M. Pasadas

2014-01-01T23:59:59.000Z

163

Two dimensional finite element analysis of homogenization and failure in plain weave textile composites  

E-Print Network (OSTI)

TWO DIMENSIONAL FINITE ELEMENT ANALYSIS OF HOMOGENIZATION AND FAILURE IN PLAIN WEAVE TEXTILE COMPOSITES A Thesis by VEERARAGHAVA GOPAL KONDAGUNTA Submitted to the Office of Graduate Studies of Texas ARM University In partial fulffllment... of the requirements for the degree of MASTER OF SCIENCE August 1993 Major Subject: Aerospace Engineering TWO DIMENSIONAL FINITE ELEMENT ANALYSIS OF HOMOGENIZATION AND FAILURE IN PLAIN WEAVE TEXTILE COMPOSITES A Thesis by VEERARAGHAVA GOPAL KONDAGUNTA...

Kondagunta, Veeraraghava Gopal

2012-06-07T23:59:59.000Z

164

Evaluation of new techniques for two dimensional finite element analysis of woven composites  

E-Print Network (OSTI)

EVALUATION OF NEW TECHNIQUES FOR TWO DIMENSIONAL FINITE ELEMENT ANALYSIS OF WOVEN COMPOSITES A Thesis by SITARAM CHOWDARY GUNDAPANENI Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment... of the requirement for the degree of MASTER OF SCIENCE DECEMBER 1992 Major Subject: Aerospace Engineering EVALUATION OF NEW TECHNIQUES FOR TWO DIMENSIONAL FINITE ELEMENT ANALYSIS OF WOVEN COMPOSITES A Thesis by SITARAM CHOWDARY GUNDAPANENI Approved...

Gundapaneni, Sitaram Chowdary

2012-06-07T23:59:59.000Z

165

A shear deformable, doubly curved finite element for the analysis of laminated composite structures  

E-Print Network (OSTI)

A SHL'AR DEFORMABLE, DOUBLY CURVED FINITE ELEMENT FOR THE ANALYSIS OF LAMINATED COMPOSITE STRUCTURES A Thesis by JOSEPH PATRICK FUEHNE Submitted to the Graduate College of Texas AE-M University in partial fulfiHment of the requirement... for the degree of MASTER OF SCIENCE May 1988 Major Subject: Mechanical Engineering A SHEAR DEFORMABLE, DOUBLY CURVED FINITE ELEMENT FOR THE ANALYSIS OF LAMINATED COMPOSITE STRUCTURES A Thesis by JOSEPH PATRICK FUEHNE Approved as to style and content by...

Fuehne, Joseph Patrick

2012-06-07T23:59:59.000Z

166

A three dimensional finite element code for the analysis of damage in helically wound composite cylinders  

E-Print Network (OSTI)

A THREE DIMENSIONAL FINITE ELEMENT CODE FOR THE ANALYSIS OF DAMAGE IN HELICALLY WOUND COMPOSITE CYLINDERS A Thesis MARVIiN AiNTHONY ZOCHER Submitted to the Office of Graduate Studies of Texas Ag:M University in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE December 1990 Major Subject; Aerospace Engineering A THREE DIMENSIONAL FINITE ELEMENT CODE FOR THE ANALYSIS OF DAMAGE IN HELICALLY WOUND COMPOSITE CYLINDERS A Thesis by i%1ARVIN ANTHONY ZOCHER Approved...

Zocher, Marvin Anthony

2012-06-07T23:59:59.000Z

167

A VECTOR FINITE ELEMENT TIME-DOMAIN METHOD FOR ...  

E-Print Network (OSTI)

gential continuity across interfaces whereas the face elements have normal continuity ..... Example: Numerical dispersion for three-dimensional shear distortion. Let ..... The error measure is the standard L2 relative error shown below,.

SIAM (#1) 1035 2001 Apr 10 12:32:38

2001-08-14T23:59:59.000Z

168

Non-periodic finite-element formulation of KohnSham density functional theory  

E-Print Network (OSTI)

Non-periodic finite-element formulation of Kohn­Sham density functional theory Phanish-element formulation for Kohn­Sham density functional theory (KS-DFT). We transform the original variational problem, dislocations and crack tips using density functional theory (DFT) at reasonable computational cost by retaining

Ortiz, Michael

169

Application of Finite Mixture Models for Vehicle Crash Data Analysis  

E-Print Network (OSTI)

heterogeneity through the use of finite mixture regression models. A Finite mixture of Poisson or NB regression models is especially useful when the count data were generated from a heterogeneous population. To evaluate these models, Poisson and NB mixture...

Park, Byung Jung

2010-07-14T23:59:59.000Z

170

Pamgen, a library for parallel generation of simple finite element meshes.  

SciTech Connect

Generating finite-element meshes is a serious bottleneck for large parallel simulations. When mesh generation is limited to serial machines and element counts approach a billion, this bottleneck becomes a roadblock. Pamgen is a parallel mesh generation library that allows on-the-fly scalable generation of hexahedral and quadrilateral finite element meshes for several simple geometries. It has been used to generate more that 1.1 billion elements on 17,576 processors. Pamgen generates an unstructured finite element mesh on each processor at the start of a simulation. The mesh is specified by commands passed to the library as a 'C'-programming language string. The resulting mesh geometry, topology, and communication information can then be queried through an API. pamgen allows specification of boundary condition application regions using sidesets (element faces) and nodesets (collections of nodes). It supports several simple geometry types. It has multiple alternatives for mesh grading. It has several alternatives for the initial domain decomposition. Pamgen makes it easy to change details of the finite element mesh and is very useful for performance studies and scoping calculations.

Foucar, James G.; Drake, Richard Roy; Hensinger, David M.; Gardiner, Thomas Anthony

2008-04-01T23:59:59.000Z

171

A semi-implicit finite element method for viscous lipid membranes  

E-Print Network (OSTI)

We propose a robust simulation method for phospholipid membranes. It is based on a mixed three-field formulation that accounts for tangential fluidity (Boussinesq-Scriven law), bending elasticity (Canham-Helfrich model) and inextensibility. The unknowns are the velocity, vector curvature and surface pressure fields, all of which are interpolated with linear continuous finite elements. The method is semi-implicit - it requires the solution of a single linear system per time step. Conditional time stability is observed, with a time step restriction that scales as the square of the mesh size. Mesh quality and refinement are maintained by adaptively remeshing. Another ingredient is a numerical force that emulates the action of an optical tweezer, allowing for virtual interaction with the membrane. Extensive relaxation experiments are reported. Comparisons to exact shapes reveal the orders of convergence for position (5/3), vector curvature (3/2), surface pressure (1) and bending energy (2). Tweezing experiments a...

Rodrigues, Diego S; Mut, Fernando; Buscaglia, Gustavo C

2014-01-01T23:59:59.000Z

172

Experimental verification of finite element enhancement and MAC methods  

E-Print Network (OSTI)

of Squares Analysis of MAC Matrices for the Pipe Model . . 128 . . 128 69. Creamer's Natural Frequencies - Pipe Model (Group 2) . . 129 LIST OF FIGURES Figure 1. Free-free Shaft Model Page 2. Cantilevered, Vertical Pipe Model 3. Graphic Illustration..., minimum changes are required in the analytical mass and stiffness matrices to produce results that match the measured natural frequency and mode shapes. Then, it is up to the analyst to assess the minimum relative change to determine the validity...

Ibrahim, Syed Azman

1991-01-01T23:59:59.000Z

173

Rayleigh's Principle in Finite Element Calculations of Seismic Wave Response  

Science Journals Connector (OSTI)

......resulting error in frequency is of second order...conserve computer storage for large models...of Seismic Wave Response Warwick D. Smith...resulting error in frequency is of second order...conserve computer storage for large models...potential and kinetic energies of the system in......

Warwick D. Smith; Bruce A. Bolt

1976-06-01T23:59:59.000Z

174

stabilized finite element methods for coupled geomechanics and ...  

E-Print Network (OSTI)

7.23 Reservoir model with two shale layers . .... Water, oil and natural gas are all fluids that exist within the pore spaces and fractures of natural reservoir rocks.

175

Finite element plate formulation including transverse shear effects for representing composite shell structures  

E-Print Network (OSTI)

For Representing Composite Shell Structures. (May 1987) Jsmil M. Hamdallah, B. S. , University of Toledo Chairman of Advisory Committee: Dr. John J. Engblom A finite element formulation for the analysis of thin to moderately thick lam- inated composite shell... in an analysis if delamination is to be avoided. The results obtained in this research confirm the potential use of the element presented as an accurate and eflicient tool in the analysis of thin to moderately thick laminated shell structures. To my parents...

Hamdallah, Jamil M.

2012-06-07T23:59:59.000Z

176

An Object-Oriented Finite Element Framework for Multiphysics Phase Field Simulations  

SciTech Connect

The phase field approach is a powerful and popular method for modeling microstructure evolution. In this work, advanced numerical tools are used to create a phase field framework that facilitates rapid model development. This framework, called MARMOT, is based on Idaho National Laboratory's finite element Multiphysics Object-Oriented Simulation Environment. In MARMOT, the system of phase field partial differential equations (PDEs) are solved simultaneously with PDEs describing additional physics, such as solid mechanics and heat conduction, using the Jacobian-Free Newton Krylov Method. An object-oriented architecture is created by taking advantage of commonalities in phase fields models to facilitate development of new models with very little written code. In addition, MARMOT provides access to mesh and time step adaptivity, reducing the cost for performing simulations with large disparities in both spatial and temporal scales. In this work, phase separation simulations are used to show the numerical performance of MARMOT. Deformation-induced grain growth and void growth simulations are included to demonstrate the muliphysics capability.

Michael R Tonks; Derek R Gaston; Paul C Millett; David Andrs; Paul Talbot

2012-01-01T23:59:59.000Z

177

Application of equivalent elastic methods in three-dimensional finite element structural analysis  

SciTech Connect

This paper describes use of equivalent solid (EQS) modeling to obtain efficient solutions to perforated material problems using three-dimensional finite element analysis (3-D-FEA) programs. It is shown that EQS modeling in 3-D-FEA requires an EQS constitutive relationship with a sufficient number of independent constants to allow the EQS material to respond according to the elastic symmetry of the penetration pattern. It is also shown that a 3-D-FEA submodel approach to calculate peak stresses and ligament stresses from EQS results is very accurate and preferred over more traditional stress multiplier approaches. The method is demonstrated on the problem of a transversely pressurized simply supported plate with a central divider lane separating two perforated regions with circular penetrations arranged in a square pattern. A 3-D-FEA solution for a model that incorporates each penetration explicitly is used for comparison with results from an EQS solution for the plate. Results for deflection and stresses from the EQS solution are within 3% of results from the explicit 3-D-FE model. A solution to the sample problem is also provided using the procedures in the ASME B and PV Code. The ASME B and PV Code formulas for plate deflection were shown to overestimate the stiffening effects of the divider lane and the outer stiffening ring.

Jones, D.P.; Gordon, J.L.; Hutula, D.N.; Holliday, J.E.; Jandrasits, W.G. [Bechtel Bettis, Inc., West Mifflin, PA (United States). Bettis Atomic Power Lab.

1999-08-01T23:59:59.000Z

178

Parallel Adaptive Finite Element Software for Semiconductor Device Simulation*  

E-Print Network (OSTI)

.9 million grid problem run on the Intel Delta machine achieved 20% efficiency using 512 nodes and con was created. Quad­ and oct­tree utilities were developed and used to support the gridding of complex IC are computationally demanding and to date the infrastructure to support large scale 3D models has been insufficient

Dutton, Robert W.

179

Finite Element Analysis of Three-Phase Piezoelectric Nanocomposites  

E-Print Network (OSTI)

on performance. The nanocomposite consisted of a polyimide matrix, beta-CN APB/ODPA, enhanced with single wall carbon nanotubes and PZT-5A particles. The polyimide and nan- otube phases were modeled as a single homogenized phase. This results in a two...

Maxwell, Kevin S.

2010-10-12T23:59:59.000Z

180

Rayleigh's Principle in Finite Element Calculations of Seismic Wave Response  

Science Journals Connector (OSTI)

......of Seismic Wave Response Warwick D. Smith...resulting error in frequency is of second order...conserve computer storage for large models...estimatesof the seismic response of irregular Earth...complex one, and this frequency is then accurate...to the potential energy and the denominator......

Warwick D. Smith; Bruce A. Bolt

1958-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling finite element" 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

Finite element-based analysis of shunted piezoelectric structures for vibration damping  

Science Journals Connector (OSTI)

Piezoelectric patches shunted with passive electrical networks can be attached to a host structure for reduction of structural vibrations. This approach is frequently called ''shunted piezo damping'' and has the advantage of guaranteed stability and ... Keywords: Finite element analysis, Passive electrical network, Piezoelectric structure, Vibration damping

Jens Becker; Oliver Fein; Matthias Maess; Lothar Gaul

2006-12-01T23:59:59.000Z

182

Computing the dynamics of biomembranes by combining conservative level set and adaptive finite element methods  

Science Journals Connector (OSTI)

The numerical simulation of the deformation of vesicle membranes under simple shear external fluid flow is considered in this paper. A saddle-point approach is proposed for the imposition of the fluid incompressibility and the membrane inextensibility ... Keywords: Adaptive finite element method, Fluid mechanics, Helfrich energy, Level set method, Mass conservation, Vesicle dynamics

Aymen Laadhari, Pierre Saramito, Chaouqi Misbah

2014-04-01T23:59:59.000Z

183

Thermo-elasto-plastic finite element analysis of quasi-state processes in Eulerian reference  

E-Print Network (OSTI)

Thermo-elasto-plastic finite element analysis of quasi-state processes in Eulerian reference frames ­ Incremental scheme ­ Fine mesh along entire heat source path ­ Lengthy computer runs · Elasto-Plasticity at times ti and ti-1, respectively. Penn State University 5 #12;Elasto-Plasticity Equilibrium: r(r, t) + b

Michaleris, Panagiotis

184

Local Flaps: A Real-Time Finite Element Based Solution to the Plastic Surgery  

E-Print Network (OSTI)

Local Flaps: A Real-Time Finite Element Based Solution to the Plastic Surgery Defect Puzzle fundamental challenges in plastic surgery is the alter- ation of the geometry and topology of the skin for the patient after the procedure is completed. The plastic surgeon must look at the defect created

Liblit, Ben

185

Finite Element Analysis of a Composite Semi-Span Test Article With and Without Discrete Damage  

Science Journals Connector (OSTI)

AS&M, Inc. performed finite element analysis, with and without discrete damage, of a composite semi-span test article that represents the Boeing 220-passenger transport aircraft composite semi-span test article. A NASTRAN bulk data file and drawings ...

Lovejoy Andrew E.

2000-08-01T23:59:59.000Z

186

On the role of boundary conditions for CIP stabilization of higher order finite elements  

E-Print Network (OSTI)

On the role of boundary conditions for CIP stabilization of higher order finite elements Friedhelm Schieweck 13.11.2007 Abstract We investigate the Continuous Interior Penalty (CIP) stabilization method even in the limit case where the parameter of the CIP stabilization is zero, i.e., where the standard

Schieweck, Friedhelm

187

Computation of incompressible bubble dynamics with a stabilized finite element level set method  

E-Print Network (OSTI)

Computation of incompressible bubble dynamics with a stabilized finite element level set method. 100 (1992) 335­354] was applied in order to account for surface tension effects. To restrict as surface tension. The capability of the resultant algorithm is demonstrated with two and three dimensional

Frey, Pascal

188

Finite element simulation of three-dimensional free-surface flow problems  

E-Print Network (OSTI)

surface. The technique is illustrated through an implementation for surface-tension-dominated viscous understanding the evolution and stability of free surfaces provides one of the major incentivesFinite element simulation of three-dimensional free-surface flow problems M.A. Walkley1 £, P

Jimack, Peter

189

Stabilized finite element formulations for liquid membranes and their application to droplet contact  

E-Print Network (OSTI)

and liquid coats. The mechanics of liquid membranes is governed by the surface tension of liquids, whichStabilized finite element formulations for liquid membranes and their application to droplet of the curvilinear coordinate system that is used for the surface description of the membrane. Particular emphasize

190

A Mixed Finite Element Approximation for Compressible Flow of Contamination from Nuclear  

E-Print Network (OSTI)

A Mixed Finite Element Approximation for Compressible Flow of Contamination from Nuclear Waste in Porous Media S. H. CHOU AND Q. LI Abstract A compressible nuclear waste disposal contamination in porous the effects of molecular diffusion and dispersion. Secondly, the ``complete compressibility'' case

Chou, So-Hsiang

191

A 2D finite element with through the thickness parabolic temperature distribution for heat transfer simulations including welding  

Science Journals Connector (OSTI)

Abstract The arc welding process involves thermal cycles that cause the appearance of undesirable residual stresses. The determination of this thermal cycle is the first step to a thermomechanical analysis that allows the numerical calculation of residual stresses. This study describes the formulation of a 2D finite element with through the thickness parabolic temperature distribution, including an element estabilization procedure. The 2D element described in this paper can be used to perform thermal analysis more economically than 3D elements, especially in plates, because the number of degrees of freedom through the thickness will always be three. A numerical model of a tungsten arc welding (GTAW) setup was made based on published experimental results. Size and distribution of the heat source input, thermal properties dependent on temperature, surface heat losses by convection and latent heat during phase change were considered. In parallel the same setup was modeled using ANSYS software with 3D elements (SOLID70) to compare against 2D numerical results. The results obtained by 2D model, 3D model and experimental data showed good agreement.

Darlesson Alves do Carmo; Alfredo Rocha de Faria

2015-01-01T23:59:59.000Z

192

An error analysis of a finite element method for a system of nonlinear advection--diffusion--reaction equations  

Science Journals Connector (OSTI)

In this paper we present an analysis of a finite element method for solving a system of nonlinear advection-diffusion-reaction equations. We prove the existence and uniqueness of the numerical solution, and obtain a prior error estimates optimal in H^1 ... Keywords: Advection--diffusion--reaction, Error estimate, Finite element, Nonlinear

Biyue Liu

2009-08-01T23:59:59.000Z

193

Finite element investigation of multi-phase transformation within carburized carbon steel  

Science Journals Connector (OSTI)

Mechanical components for the automobiles, aircrafts and machines are required to have the higher strength, hardness and wear resistance, when these parts are generally subjected to high load and impact. Such mechanical properties can be obtained from the carburization and quenching processes. Thus, in this study, numerical investigation using three-dimensional finite element technique was made to simulate the carburization and multi-phase transformation processes within the carburized carbon steel during quenching. In order to simulate the carburization process, the second Fick's equation and carbon diffusional equation were adapted. For numerical simulation of the diffusional phase transformation occurred during the non-isothermal quenching process, subdivision of the cooling curve into various small isothermal steps was introduced with the help of various time–temperature–transformation (TTT) diagrams of carbon steel. In addition, Scheil's additive rule and Johnson–Mehl–Avarami–Kolmogorov (JMAK) equation were also solved. On the other hand, Koistinen and Marburger's equation was used to model the diffusionless transformation. Through numerical analyses of carburization and quenching processes, the temperature and volume fraction of each phase were predicted for simple cylindrical specimen and complex geometries considering the latent heat generated during phase transformation. The numerical results compared well with the data available in the literature.

Seong-Hoon Kang; Yong-Taek Im

2007-01-01T23:59:59.000Z

194

Failure of Mineralized Collagen Microfibrils Using Finite Element Simulation Coupled to Mechanical Quasi-brittle Damage  

E-Print Network (OSTI)

Bone is a multiscale heterogeneous materiel of which principal function is to support the body structure and to resist mechanical loading and fractures. Bone strength does not depend only on the quantity and quality of bone which is characterized by the geometry and the shape of bones but also on the mechanical proprieties of its compounds, which have a significant influence on its deformation and failure. This work aim to use a 3D nano-scale finite element model coupled to the concept of quasi-brittle damage with the behaviour law isotropic elasticity to investigate the fracture behaviour of composite materiel collagen-mineral (mineralized collagen microfibril). Fracture stress-number of cross-links and damping capacity-number of cross-links curves were obtained under tensile loading conditions at different densities of the mineral phase. The obtained results show that number of cross-links as well as the density of mineral has an important influence on the strength of microfibrils which in turn clarify the ...

Barkaoui, Abdelwahed; Hambli, Ridha; 10.1016/j.proeng.2011.04.526

2011-01-01T23:59:59.000Z

195

Sensitivity analysis of single-layer graphene resonators using atomic finite element method  

SciTech Connect

Atomic finite element simulation is applied to study the natural frequency and sensitivity of a single-layer graphene-based resonator with CCCC, SSSS, CFCF, SFSF, and CFCF boundary conditions using the commercial code ANSYS. The fundamental frequencies of the graphene sheet are compared with the results of the previous finite element study. In addition, the sensitivity of the resonator is compared with the early work based on nonlocal elasticity theory. The results of the comparison are very good in all considered cases. The sensitivities of the resonator with different boundary conditions are obtained, and the order based on the boundary condition is CCCC > SSSS > CFCF > SFSF > CFFF. The highest sensitivity is obtained when the attached mass is located at the center of the resonator. This is useful for the design of a highly sensitive graphene-based mass sensor.

Lee, Haw-Long; Hsu, Jung-Chang; Lin, Shu-Yu; Chang, Win-Jin [Department of Mechanical Engineering, Kun Shan University, Tainan 71003, Taiwan (China)] [Department of Mechanical Engineering, Kun Shan University, Tainan 71003, Taiwan (China)

2013-09-28T23:59:59.000Z

196

Spring-supported thrust bearings used in hydroelectric generators: Finite element analysis of pad deflection  

Science Journals Connector (OSTI)

An iterative solution technique has been developed for fluid film lubrication of large spring-supported thrust bearings subject to hydrodynamic and hydrostatic lubrication using finite element analysis for pad deflection. Oil film pressures are obtained using a control volume formulation of the Reynolds equation while pad deflections are determined with a commercial finite element analysis package. Low rotor speeds are specified so that isothermal conditions prevail. A computer program links these two numerical methods to implement a solution procedure that consists of iterative loops for applied load, input flow rate, and pad deflection. Illustrative solutions have been obtained showing the influence of spring stiffness, lubricant viscosity, load, and location of the hydrostatic supply pocket.

Ms.A.L. Brown; Dr.J.B. Medley; Mr.J.H. Ferguson

2001-01-01T23:59:59.000Z

197

Three dimensional finite element methods: Their role in the design of DC accelerator systems  

SciTech Connect

High Voltage Engineering has designed, built and tested a 2 MV dual irradiation system that will be applied for radiation damage studies and ion beam material modification. The system consists of two independent accelerators which support simultaneous proton and electron irradiation (energy range 100 keV - 2 MeV) of target sizes of up to 300 Multiplication-Sign 300 mm{sup 2}. Three dimensional finite element methods were used in the design of various parts of the system. The electrostatic solver was used to quantify essential parameters of the solid-state power supply generating the DC high voltage. The magnetostatic solver and ray tracing were used to optimize the electron/ion beam transport. Close agreement between design and measurements of the accelerator characteristics as well as beam performance indicate the usefulness of three dimensional finite element methods during accelerator system design.

Podaru, Nicolae C.; Gottdang, A.; Mous, D. J. W. [High Voltage Engineering Europa B.V., P.O. Box 99, 3800 AB, Amersfoort (Netherlands)

2013-04-19T23:59:59.000Z

198

Enhanced finite element analysis using the PATRAN-G pre- and post processor program  

E-Print Network (OSTI)

the layers of a composite inaterial with nodes and orientation General overview diagram of PATRAN-G svsyteni and interfaces Finite element mesh of 36 element plate with nodes labeled Stress contour plot showing the in-plane stress in the x...-direction for layer 1 Stress contour plot showing the in-plane stress in the y-direction for layer 1 Stress contour plot showing the in-plane xy stress for layer 1 Stress contour plot showing the transverse xz stress for layer 9 Stress contour plot...

Murry, Margaret Lois

2012-06-07T23:59:59.000Z

199

Finite element simulation of moisture movement and solute transport in a large caisson  

SciTech Connect

The results of the solute transport experiments performed on compacted, crushed Bandelier Tuff in caisson B of the experimental cluster described by DePoorter (1981) are simulated. Both one- and three-dimensional simulations of solute transport have been performed using two selected finite element codes. Results of bromide and iodide tracer experiments conducted during near-steady flow conditions have been analyzed for pulse additions made on December 6, 1984, and followed over a period of up to 60 days. In addition, a pulse addition of nonconservative strontium tracer on September 28, 1984, during questionably steady flow conditions has been analyzed over a period of 240 days. One-dimensional finite element flow and transport simulations were carried out assuming the porous medium to be homogeneous and the injection source uniformly distributed. To evaluate effects of the nonuniform source distribution and also to investigate effects of inhomogeneous porous medium properties, three dimensional finite element analyses of transport were carried out. Implications of the three-dimensional effects for the design and analysis of future tracer studies are discussed.

Huyakorn, P.S.; Jones, B.G.; Parker, J.C.; Wadsworth, T.D.; White, H.O. Jr.

1987-04-01T23:59:59.000Z

200

An operator-customized wavelet-finite element approach for the adaptive solution of second-order partial differential equations on unstructured meshes  

E-Print Network (OSTI)

The Finite Element Method (FEM) is a widely popular method for the numerical solution of Partial Differential Equations (PDE), on multi-dimensional unstructured meshes. Lagrangian finite elements, which preserve C? continuity ...

D'Heedene, Stefan F., 1977-

2005-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling finite element" 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

Finite element analysis of bending in a threaded connector for a 5 1/2-in. Marine riser  

SciTech Connect

This paper describes the development of a new finite element modelling technique for performing nonlinear bending analysis of tubulars and its application to a threaded connector for a 5-1/2 inch production tubing marine riser. A finite element technique has been developed for analyzing bending loads applied to an axisymmetric geometry. The method uses a Fourier series solution. The first two terms of the series are solved simultaneously, allowing nonlinearities to be included since the method does not use superposition, which normally requires linearity. Existing methods of analysis require either a linear elastic assumption, and axisymmetric approximation of bending loads, or a full three dimensional analysis. The new technique includes nonlinearities in mechanical properties, gapping, and friction. It is more accurate than the method where axisymmetric loads are applied so that pipe OD stresses are the same as those that would result from bending. The model is considerably less complicated to use than a three dimensional model and is also considerably less expensive. The method described above is applied to a 5-1/2 inch threaded connector. The connector is analyzed under make-up, tension, pressure, bending, and shear loads. Predictions include average and reversing stresses in the pin and box wall and at stress concentrations. These predictions can be used to evaluate the fatigue life of the connector.

Allen, M.B.; Eichberger, L.C.

1984-05-01T23:59:59.000Z

202

Time-independent hybrid enrichment for finite element solution of transient conduction–radiation in diffusive grey media  

SciTech Connect

We investigate the effectiveness of the partition-of-unity finite element method for transient conduction–radiation problems in diffusive grey media. The governing equations consist of a semi-linear transient heat equation for the temperature field and a stationary diffusion approximation to the radiation in grey media. The coupled equations are integrated in time using a semi-implicit method in the finite element framework. We show that for the considered problems, a combination of hyperbolic and exponential enrichment functions based on an approximation of the boundary layer leads to improved accuracy compared to the conventional finite element method. It is illustrated that this approach can be more efficient than using h adaptivity to increase the accuracy of the finite element method near the boundary walls. The performance of the proposed partition-of-unity method is analyzed on several test examples for transient conduction–radiation problems in two space dimensions.

Mohamed, M. Shadi, E-mail: m.s.mohamed@durham.ac.uk [School of Engineering and Computing Sciences, University of Durham, South Road, Durham DH1 3LE (United Kingdom); Seaid, Mohammed; Trevelyan, Jon [School of Engineering and Computing Sciences, University of Durham, South Road, Durham DH1 3LE (United Kingdom)] [School of Engineering and Computing Sciences, University of Durham, South Road, Durham DH1 3LE (United Kingdom); Laghrouche, Omar [Institute for Infrastructure and Environment, Heriot-Watt University, Edinburgh EH14 4AS (United Kingdom)] [Institute for Infrastructure and Environment, Heriot-Watt University, Edinburgh EH14 4AS (United Kingdom)

2013-10-15T23:59:59.000Z

203

Finite element analysis of laminar mixed convection in the entrance region of horizontal annular ducts  

SciTech Connect

The laminar mixed convection in the entrance region of horizontal straight ducts of an annular cross section is studied by means of a generally applicable finite element procedure based on the parabolized simplification of the Navier-Stokes and energy equations and on the Boussinesq approximation of the buoyancy term. The procedure is validated through comparisons of computed results with available data from the literature. New results concern annuli with radius ratios equal to 0.25, 0.5, and 0.75 subjected to the fundamental boundary condition of the second and the third kinds, for Prandtl numbers equal to 0.7 and 7, and different values of Grashof number.

Nonino, C.; Giudice, S. del [Univ. di Udine (Italy). Dipt. di Energetica e Macchine

1996-02-23T23:59:59.000Z

204

On the stability of bubble functions and a stabilized mixed finite element formulation for the Stokes problem  

E-Print Network (OSTI)

In this paper we investigate the relationship between stabilized and enriched finite element formulations for the Stokes problem. We also present a new stabilized mixed formulation for which the stability parameter is derived purely by the method of weighted residuals. This new formulation allows equal order interpolation for the velocity and pressure fields. Finally, we show by counterexample that a direct equivalence between subgrid-based stabilized finite element methods and Galerkin methods enriched by bubble functions cannot be constructed for quadrilateral and hexahedral elements using standard bubble functions.

Turner, D Z; Hjelmstad, K D

2008-01-01T23:59:59.000Z

205

Parallel Computations of Natural Convection Flow in a Tall Cavity Using an Explicit Finite Element Method  

SciTech Connect

The Galerkin Finite Element Method was used to predict a natural convection flow in an enclosed cavity. The problem considered was a differentially heated, tall (8:1), rectangular cavity with a Rayleigh number of 3.4 x 10{sup 5} and Prandtl number of 0.71. The incompressible Navier-Stokes equations were solved using a Boussinesq approximation for the buoyancy force. The algorithm was developed for efficient use on massively parallel computer systems. Emphasis was on time-accurate simulations. It was found that the average temperature and velocity values can be captured with a relatively coarse grid, while the oscillation amplitude and period appear to be grid sensitive and require a refined computation.

Dunn, T.A.; McCallen, R.C.

2000-10-17T23:59:59.000Z

206

Optimal design of switched reluctance motor using two-dimensional finite element method  

Science Journals Connector (OSTI)

Switched reluctance motor (SRM) has some advantages such as low cost high torque density etc. but SRM has essentially high torque ripple due to its salient structure. To apply SRM to the industrial field we have to minimize torque ripple which is the weak point of SRM. This article introduces optimal design process of SRM using a numerical method such as two-dimensional (2D) finite element method. The electrical and geometrical design parameters have been adopted as 2D design variables. From this work we can obtain the optimal design which minimizes the torque ripple. We also can obtain the optimal design which maximizes the average torque. Finally this article presents performance comparison of two optimal designs the minimized torque ripple and the maximized average torque.

Youn-Hyun Kim; Jae-Hak Choi; Sung-In Jung; Sol Kim; Ju Lee; Min-Sik Chu; Kyung-Jin Hong; Dong-Hoon Choi

2002-01-01T23:59:59.000Z

207

An angularly refineable phase space finite element method with approximate sweeping procedure  

SciTech Connect

An angularly refineable phase space finite element method is proposed to solve the neutron transport equation. The method combines the advantages of two recently published schemes. The angular domain is discretized into small patches and patch-wise discontinuous angular basis functions are restricted to these patches, i.e. there is no overlap between basis functions corresponding to different patches. This approach yields block diagonal Jacobians with small block size and retains the possibility for S{sub n}-like approximate sweeping of the spatially discontinuous elements in order to provide efficient preconditioners for the solution procedure. On the other hand, the preservation of the full FEM framework (as opposed to collocation into a high-order S{sub n} scheme) retains the possibility of the Galerkin interpolated connection between phase space elements at arbitrary levels of discretization. Since the basis vectors are not orthonormal, a generalization of the Riemann procedure is introduced to separate the incoming and outgoing contributions in case of unstructured meshes. However, due to the properties of the angular discretization, the Riemann procedure can be avoided at a large fraction of the faces and this fraction rapidly increases as the level of refinement increases, contributing to the computational efficiency. In this paper the properties of the discretization scheme are studied with uniform refinement using an iterative solver based on the S{sub 2} sweep order of the spatial elements. The fourth order convergence of the scalar flux is shown as anticipated from earlier schemes and the rapidly decreasing fraction of required Riemann faces is illustrated. (authors)

Kophazi, J.; Lathouwers, D. [Faculty of Applied Sciences, Delft University of Technology, Mekelweg 15, NL-2629 JB Delft (Netherlands)

2013-07-01T23:59:59.000Z

208

Stress development and shape change during press-hardening process using phase-transformation-based finite element analysis  

Science Journals Connector (OSTI)

Abstract Elastically driven shape change, or springback, in a press-hardened U-channel part made from a tailor-welded blank (TWB) was simulated using a fully coupled thermo-mechanical–metallurgical finite element (FE) method. The TWB consists of boron steel and high-strength low-alloy steel, which have significantly different hardenabilities. A combined implicit–explicit three-step simulation consisting of air cooling, forming and die quenching, and springback was used for computational efficiency. All the required material models such as the modified phase-transformation kinetics and phase-transformation-related stress-update scheme were implemented in the FE software ABAQUS with the user-defined subroutines UMAT, VUMAT, and HETVAL. The developed FE procedure, including the material models, satisfactorily predicted the experimentally measured shape changes of the TWB part. Here we present an in-depth analysis of the residual stress development during forming and die quenching using different material modeling schemes. It should be noted that the stress evolution of the two materials with high and low hardenabilities were significantly different depending on the phase transformation kinetics during forming and quenching. Moreover, in order to enhance the prediction capability of the press-hardening simulations, it was essential to include the phase-transformation-related strains in the material model.

H.H. Bok; J.W. Choi; D.W. Suh; M.G. Lee; F. Barlat

2014-01-01T23:59:59.000Z

209

Fourier-Finite Element Method with linear basis functions on the sphere: Application to elliptic- and transport-equations  

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Fourier-Finite Element Method (FFEM) on the sphere, which performs with operation count of O(N2 log2 N) for 2N × N grids in spherical coordinates, was developed using linear basis functions. Dependent field variables are expanded with the Fourier ...

Hyeong-Bin Cheong; Hae-Jin Kong; Hyun-Gyu Kang; Jae-Deok Lee

210

A ThreeDimensional Finite Element Simulation for Transport of Nuclear Waste Contamination in Porous Media \\Lambda  

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A Three­Dimensional Finite Element Simulation for Transport of Nuclear Waste Contamination for transport of nuclear­waste contamination in three­dimensional porous media are presented with a description of contamination of groundwater by high­level nuclear waste and a wide variety of other sources makes a proper

Ewing, Richard E.

211

1100 IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING, VOL. 50, NO. 9, SEPTEMBER 2003 Finite-Element Time-Domain Algorithms for  

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frequencies in the context of finite-element time-domain (FETD) numerical solutions of electric potential. The new algorithms, which permit treatment of multiple-pole dielectric relaxations, are based on the auxiliary differential equation method and are unconditionally stable. We validate the algorithms

212

Finite Element Solution of Nonlinear Transient Rock Damage with Application in Geomechanics of Oil and Gas Reservoirs  

E-Print Network (OSTI)

the geomechanics of oil and gas reservoirs. The fragile microstructure of some rocks makes it difficult to predict of Steel, Aluminum, Concrete, etc. Moreover, the pattern of rock damage in oil and gas reservoirsFinite Element Solution of Nonlinear Transient Rock Damage with Application in Geomechanics of Oil

Patzek, Tadeusz W.

213

Numerical Stochastic Homogenization Method and Multiscale Stochastic Finite Element Method - A Paradigm for Multiscale Computation of Stochastic PDEs  

SciTech Connect

Multiscale modeling of stochastic systems, or uncertainty quantization of multiscale modeling is becoming an emerging research frontier, with rapidly growing engineering applications in nanotechnology, biotechnology, advanced materials, and geo-systems, etc. While tremendous efforts have been devoted to either stochastic methods or multiscale methods, little combined work had been done on integration of multiscale and stochastic methods, and there was no method formally available to tackle multiscale problems involving uncertainties. By developing an innovative Multiscale Stochastic Finite Element Method (MSFEM), this research has made a ground-breaking contribution to the emerging field of Multiscale Stochastic Modeling (MSM) (Fig 1). The theory of MSFEM basically decomposes a boundary value problem of random microstructure into a slow scale deterministic problem and a fast scale stochastic one. The slow scale problem corresponds to common engineering modeling practices where fine-scale microstructure is approximated by certain effective constitutive constants, which can be solved by using standard numerical solvers. The fast scale problem evaluates fluctuations of local quantities due to random microstructure, which is important for scale-coupling systems and particularly those involving failure mechanisms. The Green-function-based fast-scale solver developed in this research overcomes the curse-of-dimensionality commonly met in conventional approaches, by proposing a random field-based orthogonal expansion approach. The MSFEM formulated in this project paves the way to deliver the first computational tool/software on uncertainty quantification of multiscale systems. The applications of MSFEM on engineering problems will directly enhance our modeling capability on materials science (composite materials, nanostructures), geophysics (porous media, earthquake), biological systems (biological tissues, bones, protein folding). Continuous development of MSFEM will further contribute to the establishment of Multiscale Stochastic Modeling strategy, and thereby potentially to bring paradigm-shifting changes to simulation and modeling of complex systems cutting across multidisciplinary fields.

X. Frank Xu

2010-03-30T23:59:59.000Z

214

Deforming fluid domains within the finite element method: Five mesh-based tracking methods in comparison  

E-Print Network (OSTI)

Fluid flow applications can involve a number of coupled problems. One is the simulation of free-surface flows, which require the solution of a free-boundary problem. Within this problem, the governing equations of fluid flow are coupled with a domain deformation approach. This work reviews five of those approaches: interface tracking using a boundary-conforming mesh and, in the interface capturing context, the level-set method, the volume-of-fluid method, particle methods, as well as the phase-field method. The history of each method is presented in combination with the most recent developments in the field. Particularly, the topics of extended finite elements (XFEM) and NURBS-based methods, such as Isogeometric Analysis (IGA), are addressed. For illustration purposes, two applications have been chosen: two-phase flow involving drops or bubbles and sloshing tanks. The challenges of these applications, such as the geometrically correct representation of the free surface or the incorporation of surface tension ...

Elgeti, Stefanie

2015-01-01T23:59:59.000Z

215

Finite element analysis of a crack tip in silicate glass: No evidence for a plastic zone  

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Recently, the claim was made that cracks in silicate glasses propagate by the nucleation, growth, and coalescence of cavities at crack tips, which is the same way as in metals but at a much smaller scale. This hypothesis for crack growth is based in part on the measurement of surface displacements near the tip of an emerging crack, which is the point at which a crack front intersects the side surface of the specimen. Surface displacements measured by atomic force microscopy were less than theoretically predicted. The difference between the theoretical and experimental displacements was attributed to a plastic zone surrounding the tip of the moving crack. In this paper, we show that the theoretical analysis used earlier was based on an incorrect assumption about the functional dependence of the displacement with distance from the crack tip. We use a full three-dimensional finite element analysis combined with an asymptotic solution of the crack geometry to obtain a solution to the surface displacement problem. We show that the calculated displacements are fully consistent with those experimentally measured by using an atomic force microscope. No divergence from elastic behavior is observed. Our results support the view that crack propagation in glass is entirely brittle. No evidence for plasticity at the crack tips is obtained.

T. Fett, G. Rizzi, D. Creek, S. Wagner, J. P. Guin, J. M. López-Cepero, and S. M. Wiederhorn

2008-05-15T23:59:59.000Z

216

Finite element modeling of SHTE and PSVTM electroseismics  

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ties of the presented methodology to detect gas (oil) saturated thin layers are shown. ... In geophysical exploration, the electro-osmosis phenomenon is known as .... between electromagnetic and mechanical processes is represented in the above ...... developments suggest viable applications in exploration and production.

zyserman

217

One dimensional electroseismic modeling using the finite element ...  

E-Print Network (OSTI)

The symbols ?i,j, i=b,t, j=B,M denote the bottom and top boundaries, ...... suggest viable applications in exploration and production”, 75th SEG Annual Meeting,.

2013-01-30T23:59:59.000Z

218

A Mixed Finite Element Framework for Modeling Coupled Fluid Flow ...  

E-Print Network (OSTI)

such as recovery from compaction drive, waterflooding, surface subsidence, seal in- tegrity ...... and for rocks and concrete it is in the range of 0.4-0.6. ...... incorporate into the programs an automatic, self-adaptive, procedure which adjusts.

Birendra Jha

2005-10-03T23:59:59.000Z

219

Finite element modeling of hydraulic fracturing in 3D  

E-Print Network (OSTI)

Mar 22, 2013 ... Two examples of hydraulic fracturing are given. when the pressure buildup ... Hydraulic fracturing is the coupled dynamics of frac- ture and ?uid ...

2013-03-22T23:59:59.000Z

220

Finite-element modelling: a new tool for the biologist  

Science Journals Connector (OSTI)

...distributed computing 1. Introduction Car manufacturers do not destroy thousands...be used to either replace their defective counterparts or to perform entirely...application is in the design of car crash- worthiness. Cars must both protect the occupants...

2000-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling finite element" 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

Parallel finite element modeling of earthquake ground response and liquefaction  

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Machines Corporation (IBM). Arduino, P. , Kramer, S. , and2000; Shao and Desai 2000; Arduino et al. 2001). Currently,

Lu, Jinchi

2006-01-01T23:59:59.000Z

222

Finite element analysis and design of large diameter flexible vertical pipes subjected to incremental compacted backfill loads and creep effects  

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FINITE ELEMENT ANALYSIS AND DESiGN OF LARGE DIANETER FLEXIBLE VERTICAL PIPES SUBJECTED TO INCREMENTAL COMPACTED BACKFILL LOADS AND CREEP EFFECTS A Thesis by MOHAMMAD KABIR HOSSAIN Submitted to the Office of Graduate Studies of Texas A... BACKFILL LOADS AND CREEP EFFECTS A Thesis by MOHAMMAD KABIR HOSSAIN Approved as to sty1e and content by: R be+r L. Lytton (Chair of Committee) Ozden 0. Ochoa (Member) Derek V. Morris (Member) ames T P Yao (Head of rtment) ABSTRACT Finite...

Hossain, Mohammad Kabir

2012-06-07T23:59:59.000Z

223

Nonlinear acceleration of a continuous finite element discretization of the self-adjoint angular flux form of the transport equation  

SciTech Connect

Nonlinear acceleration of a continuous finite element (CFE) discretization of the transport equation requires a modification of the transport solution in order to achieve local conservation, a condition used in nonlinear acceleration to define the stopping criterion. In this work we implement a coarse-mesh finite difference acceleration for a CFE discretization of the second-order self adjoint angular flux (SAAF) form of the transport equation and use a post processing to enforce local conservation. Numerical results are given for one-group source calculations of one-dimensional slabs. We also give a formal derivation of the boundary conditions for the SAAF. (authors)

Sanchez, R. [Commissariat a l'Energie Atomique et Aux Energies Alternatives, Service des Etudes des Reacteurs et de Mathematiques Appliquees, CEA DEN/DM2S/SERMA, 91191 Gif-sur-Yvettes Cedex (France); Rabiti, C.; Wang, Y. [Idaho National Laboratory, 2525 Fremont Avenue, Idaho Falls, ID 83415 (United States)

2012-07-01T23:59:59.000Z

224

2-D discrete element modeling of unconsolidated sandstones.  

E-Print Network (OSTI)

??In this work unconsolidated sands saturated with heavy oil were modeled using a discrete element numerical model, (DEM). The DEM code was built in Mathematica… (more)

Franquet Barbara, Javier Alejandro

2012-01-01T23:59:59.000Z

225

Efficient periodic band diagram computation using a finite element method, Arnoldi eigensolver and sparse linear system solver  

E-Print Network (OSTI)

We present here a Finite Element Method devoted to the simulation of 3D periodic structures of arbitrary geometry. The numerical method based on ARPACK and PARDISO libraries, is discussed with the aim of extracting the eigenmodes of periodical structures and thus establishing their frequency band gaps. Simulation parameters and the computational optimization are the focus. Resolution will be used to characterize EBG (Electromagnetic Band Gap) structures, such as plasma rods and metallic cubes.

Garnier, Romain; Pascal, Olivier

2014-01-01T23:59:59.000Z

226

A finite-patch model of a flexible plate via Kane's dynamics  

Science Journals Connector (OSTI)

Military hardware must undergo extensive shock-response analysis to predict survivability to mechanical shock. Although finite element modelling is commonly used to model such hardware, alternative methods which offer the possibility of shorter modelling, modification, or simulation times continue to be desirable. This research effort applies Kane's dynamics to the problem of plate modelling, toward shock-response analysis of homogeneous plates having various geometries and boundary conditions. Analytical equations of motion are found for a continuous flexible plate that is discretised in checkerboard fashion as a patchwork of rigid rectangular patches connected by flexible springs and damped modally. A MATLAB implementation is used to validate the model against pertinent analytical and numerical benchmark analyses, for a variety of boundary conditions. The model is then reduced by applying non-holonomic constraints directly using Kane's method, and revalidated via MATLAB for a rectangular plate in simple support.

R. David Hampton

2012-01-01T23:59:59.000Z

227

Parallel Solution of the Wave Equation Using Higher Order Finite Elements  

E-Print Network (OSTI)

by stability constraints. One wants to do the same when solving with fi­ nite elements. However, except for preserving the stability of the scheme. We describe the new elements, referring the reader to [3] or [12 b = â?? 1 â?? 2 â?? 3 is a ``bubble'' function. The additional degree of freedom is the function value

Kern, Michel

228

Hypersonic Heat Transfer and Anisotropic Visualization with a Higher Order Discontinuous Galerkin Finite Element Method  

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Hypersonic Heat Transfer and Anisotropic Visualization with a Higher Order Discontinuous Galerkin;Hypersonic Heat Transfer and Anisotropic Visualization with a Higher Order Discontinuous Galerkin Finite used to predict heat transfer to a cylinder in a hypersonic flow. The strong shock is captured

Peraire, Jaime

229

Assessment of ground vibration impact from automotive and transit sources on future biotechnology research center using finite element analysis (FEA)  

Science Journals Connector (OSTI)

A new science and biotechnology research center was to be built in a metropolitan industrial area. There was concern that ground vibration from a nearby freeway street traffic and trains on an adjacent railroad would impact vibration sensitive research equipment inside the building. Ground vibration was measured at the project site prior to construction. Finite Element Analysis(FEA) was used to develop a computer simulation of the building structure using the measured ground vibration as input to the FEAmodel. The study determined the building floor vibration due to exterior sources would achieve the project’s criteria for the building structure as designed.

James E. Phillips

2007-01-01T23:59:59.000Z

230

An outgoing energy flux boundary condition for finite difference ICRP antenna models  

SciTech Connect

For antennas at the ion cyclotron range of frequencies (ICRF) modeling in vacuum can now be carried out to a high level of detail such that shaping of the current straps, isolating septa, and discrete Faraday shield structures can be included. An efficient approach would be to solve for the fields in the vacuum region near the antenna in three dimensions by finite methods and to match this solution at the plasma-vacuum interface to a solution obtained in the plasma region in one dimension by Fourier methods. This approach has been difficult to carry out because boundary conditions must be imposed at the edge of the finite difference grid on a point-by-point basis, whereas the condition for outgoing energy flux into the plasma is known only in terms of the Fourier transform of the plasma fields. A technique is presented by which a boundary condition can be imposed on the computational grid of a three-dimensional finite difference, or finite element, code by constraining the discrete Fourier transform of the fields at the boundary points to satisfy an outgoing energy flux condition appropriate for the plasma. The boundary condition at a specific grid point appears as a coupling to other grid points on the boundary, with weighting determined by a kemel calctdated from the plasma surface impedance matrix for the various plasma Fourier modes. This boundary condition has been implemented in a finite difference solution of a simple problem in two dimensions, which can also be solved directly by Fourier transformation. Results are presented, and it is shown that the proposed boundary condition does enforce outgoing energy flux and yields the same solution as is obtained by Fourier methods.

Batchelor, D.B.; Carter, M.D.

1992-11-01T23:59:59.000Z

231

DYNA3D: A nonlinear, explicit, three-dimensional finite element code for solid and structural mechanics, User manual. Revision 1  

SciTech Connect

This report is the User Manual for the 1993 version of DYNA3D, and also serves as a User Guide. DYNA3D is a nonlinear, explicit, finite element code for analyzing the transient dynamic response of three-dimensional solids and structures. The code is fully vectorized and is available on several computer platforms. DYNA3D includes solid, shell, beam, and truss elements to allow maximum flexibility in modeling physical problems. Many material models are available to represent a wide range of material behavior, including elasticity, plasticity, composites, thermal effects, and rate dependence. In addition, DYNA3D has a sophisticated contact interface capability, including frictional sliding and single surface contact. Rigid materials provide added modeling flexibility. A material model driver with interactive graphics display is incorporated into DYNA3D to permit accurate modeling of complex material response based on experimental data. Along with the DYNA3D Example Problem Manual, this document provides the information necessary to apply DYNA3D to solve a wide range of engineering analysis problems.

Whirley, R.G.; Engelmann, B.E.

1993-11-01T23:59:59.000Z

232

Dynamic analysis of shells of revolution submerged in an acoustic medium by the finite element method  

E-Print Network (OSTI)

of the spherical shell transformation matrix relating (q} and (u) for an element generalized added mass matrix due to radiated pressure matrix relating (q) and (I) for an element unknown source strength velocity of sound in fluid coupled equivalent nodal load... A method 1s presented for the evaluation of the displacements and the surface pressure which are induced by the harmonic exc1tation of a shell of revolution submerged in an acoustic medium. The method utilizes a source distribution approach...

Ng, Chi Kin

1978-01-01T23:59:59.000Z

233

Incorporation and modification of a shear deformable finite element into MARC  

E-Print Network (OSTI)

Calculation. Failure Progression Prediction. 2 4 6 8 9 10 QHD40 ELEMENT FUNDAMENTALS . . Review of QHD40 Element Displacement Field. Constitutive Relations. Interlaminar Stresses. 12 12 15 16 TAPER FORMULATION. 20 Taper Capabilities... 42 Cantilevered tapered plate . Page 65 43 Cross-sectional view of tapered laminate 44 Cantilevered plate with Sxg mesh and boundary conditions . . . . . 68 45 Tapered vs. flat plate deflection. . 69 46 Tapered plate transverse displacement. 47...

Hofman, Brad Burdell

2012-06-07T23:59:59.000Z

234

Implementation of B-splines in a Conventional Finite Element Framework  

E-Print Network (OSTI)

continu- ity requirements for classical plate analysis. There is very good agreement between analytical and existing numerical solutions. PengCheng et al. utilized a multivariable spline element method to perform vibration analysis of plates [28... continu- ity requirements for classical plate analysis. There is very good agreement between analytical and existing numerical solutions. PengCheng et al. utilized a multivariable spline element method to perform vibration analysis of plates [28...

Owens, Brian C.

2010-01-16T23:59:59.000Z

235

A MIXED FINITE ELEMENT--FINITE VOLUME FORMULATION OF THE BLACKOIL MODEL #  

E-Print Network (OSTI)

three independent components (oil, gas, and water) form the three phases (liquid, vapor, and aqua. The two chemical components, oil and gas, represent ideal mean hydrocarbons. At standard pressure and temperature (``stock­tank'' conditions or STC), the ``oil'' hydrocarbon will be present in the liquid phase

Bergamaschi, Luca

236

Comparasion of finite difference and finite element hydrodynamic models applied to the Laguna Madre Estuary, Texas  

E-Print Network (OSTI)

Station. Calibrated Velocity at the Humble Channd Station. . Calibrated Vdocity at the GIWW at JFK Causeway Station . . Calibrated Velocity at the GIWW Marker 199 Station. Calibrated Velocity at the North of Bagm Bay Station. Calibrated Velocity... Station. . . . . . . . . . Comparison of Velocity at the Humble Channel Station . Page 63 63 67 67 67 68 68 71 71 71 72 72 72 73 73 74 79 80 82 82 82 83 83 &3 LIST OF FIGURES - continued 61 62 63 65 66 67 68 Comparison...

McArthur, Karl Edward

2012-06-07T23:59:59.000Z

237

A finite difference model for low frequency sound measurement in kraft recovery boilers.  

Science Journals Connector (OSTI)

Kraft recovery boilers greatly enhance the efficiency of paper pulp mills by burning the organic wastes recovered from the pulp making process and generating electricity but significant smelt?water explosion hazards exist when steam is used as the working fluid due to sodiumcompounds in the sludge from the waste incineration process. Current practice is to use acoustic emission sensors to monitor for leaks in the bottom wall and to initiate an automatic shutdown sequence for the boiler once a leak is detected. A high?frequency model previously developed by the authors and verified by measurements performed in Skoghall Sweden indicated strong attenuation in the sludge between the point of leakage and the detectors but experimental results demonstrated a pass band at low frequencies (under 20 kHz). In this paper the authors develop a two?degree?of?freedom finite difference model for the prediction of acoustic attenuation at low frequencies. The bottom wall is modeled as a periodic tube and fin arrangement and a time?domain finite difference method is used whereby the fin and tube are simple lumped elements. The model is then compared to previous experimental results with which excellent agreement is obtained.

Robert Hildebrand; Matthew Carroll; Ville Jarvinen; Juha Miettinen

2010-01-01T23:59:59.000Z

238

A finite difference model for free surface gravity drainage  

SciTech Connect

The unconfined gravity flow of liquid with a free surface into a well is a classical well test problem which has not been well understood by either hydrologists or petroleum engineers. Paradigms have led many authors to treat an incompressible flow as compressible flow to justify the delayed yield behavior of a time-drawdown test. A finite-difference model has been developed to simulate the free surface gravity flow of an unconfined single phase, infinitely large reservoir into a well. The model was verified with experimental results in sandbox models in the literature and with classical methods applied to observation wells in the Groundwater literature. The simulator response was also compared with analytical Theis (1935) and Ramey et al. (1989) approaches for wellbore pressure at late producing times. The seepage face in the sandface and the delayed yield behavior were reproduced by the model considering a small liquid compressibility and incompressible porous medium. The potential buildup (recovery) simulated by the model evidenced a different- phenomenon from the drawdown, contrary to statements found in the Groundwater literature. Graphs of buildup potential vs time, buildup seepage face length vs time, and free surface head and sand bottom head radial profiles evidenced that the liquid refills the desaturating cone as a flat moving surface. The late time pseudo radial behavior was only approached after exaggerated long times.

Couri, F.R.; Ramey, H.J. Jr.

1993-09-01T23:59:59.000Z

239

Fast finite-element calculation of gravity anomaly in complex geological regions  

Science Journals Connector (OSTI)

......accuracy of the FFEM in handling problems where the geometry...distribution of the material body are both far from...heterogeneity in the material body on the accuracy...Fig. 2). Figure 2 Diagram showing the geometry...The dimensions of the material body elements, empty......

Yongen Cai; Chi-yuen Wang

2005-09-01T23:59:59.000Z

240

Finite-difference modeling of commercial aircraft using TSAR  

SciTech Connect

Future aircraft may have systems controlled by fiber optic cables, to reduce susceptibility to electromagnetic interference. However, the digital systems associated with the fiber optic network could still experience upset due to powerful radio stations, radars, and other electromagnetic sources, with potentially serious consequences. We are modeling the electromagnetic behavior of commercial transport aircraft in support of the NASA Fly-by-Light/Power-by-Wire program, using the TSAR finite-difference time-domain code initially developed for the military. By comparing results obtained from TSAR with data taken on a Boeing 757 at the Air Force Phillips Lab., we hope to show that FDTD codes can serve as an important tool in the design and certification of U.S. commercial aircraft, helping American companies to produce safe, reliable air transportation.

Pennock, S.T.; Poggio, A.J.

1994-11-15T23:59:59.000Z

Note: This page contains sample records for the topic "modeling finite element" 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

Parallelization of the Red-Black Algorithm on Solving the Second-Order PN Transport Equation with the Hybrid Finite Element Method  

SciTech Connect

The Red-Black algorithm has been successfully applied on solving the second-order parity transport equation with the PN approximation in angle and the Hybrid Finite Element Method (HFEM) in space, i.e., the Variational Nodal Method (VNM) [1,2,3,4,5]. Any transport solving techniques, including the Red-Black algorithm, need to be parallelized in order to take the advantage of the development of supercomputers with multiple processors for the advanced modeling and simulation. To our knowledge, an attempt [6] was done to parallelize it, but it was devoted only to the z axis plans in three-dimensional calculations. General parallelization of the Red-Black algorithm with the spatial domain decomposition has not been reported in the literature. In this summary, we present our implementation of the parallelization of the Red-Black algorithm and its efficiency results.

Yaqi Wang; Cristian Rabiti; Giuseppe Palmiotti

2011-06-01T23:59:59.000Z

242

An artificial-neural-network method for the identification of saturated turbogenerator parameters based on a coupled finite-element/state-space computational algorithm  

SciTech Connect

An artificial neural network (ANN) is used in the identification of saturated synchronous machine parameters under diverse operating conditions. The training data base for the ANN is generated by a time-stepping coupled finite-element/state-space (CFE-SS) modeling technique which is used in the computation of the saturated parameters of a 20-kV, 733-MVA, 0.85 pf (lagging) turbogenerator at discrete load points in the P-Q capability plane for three different levels of terminal voltage. These computed parameters constitute a learning data base for a multilayer ANN structure which is successfully trained using the back-propagation algorithm. Results indicate that the trained ANN can identify saturated machine reactances for arbitrary load points in the P-Q plane with an error less than 2% of those values obtained directly from the CFE-SS algorithm. Thus, significant savings in computational time are obtained in such parameter computation tasks.

Chaudhry, S.R.; Ahmed-Zaid, S. [Clarkson Univ., Potsdam, NY (United States). Electrical and Computer Engineering Dept.] [Clarkson Univ., Potsdam, NY (United States). Electrical and Computer Engineering Dept.; Demerdash, N.A. [Marquette Univ., Milwaukee, WI (United States). Electrical and Computer Engineering Dept.] [Marquette Univ., Milwaukee, WI (United States). Electrical and Computer Engineering Dept.

1995-12-01T23:59:59.000Z

243

Linkage analysis with an alternative formulation for the mixed model of inheritance: The finite polygenic mixed model  

SciTech Connect

This paper presents an extension of the finite polygenic mixed model of Fernando et al. to linkage analysis. The finite polygenic mixed model, extended for linkage analysis, leads to a likelihood that can be calculated using efficient algorithms developed for oligogenic models. For comparison, linkage analysis of 5 simulated 4021-member pedigrees was performed using the usual mixed model of inheritance, approximated by Hasstedt, and the finite polygenic mixed model extended for linkage analysis presented here. Maximum likelihood estimates of the finite polygenic mixed model could be inferred to be closer to the simulated values in these pedigrees. 31 refs., 2 tabs.

Stricker, C. [Swiss Federal Institute of Technology, Zuerich (Switzerland); Fernando, R.L. [Louisiana State Univ., New Orleans, LA (United States); Elston, R.C. [Univ. of Illinois, Urbana, IL (United States)

1995-12-01T23:59:59.000Z

244

Three-dimensional finite difference time domain modeling of the Earth-ionosphere cavity resonances  

E-Print Network (OSTI)

domain (FDTD) model of Schumann resonances (SR) with a set of classical eigenfrequency and quality factorThree-dimensional finite difference time domain modeling of the Earth-ionosphere cavity resonances-dimensional finite difference time domain modeling of the Earth-ionosphere cavity resonances, Geophys. Res. Lett., 32

Pasko, Victor

245

A Finite Element-Multibody Dynamics Co-simulation Methodology Applied to FAST  

E-Print Network (OSTI)

6 6 4 (Qv)R (Qv) (Qv)f 3 7 7 7 7 5 (2.7) The assembly is accomplished using a Boolean transformation matrix [24] which 23 identi es the connectivity conditions between the elements. The mass and sti ness matrix is given by the rst... external forces and Qv is the quadratic velocity vector. The detailed expression for the terms in the matrices is given by Shabana [24]. For the studies herein, the turbine rotation con ned to the rotor plane is assumed. Also, the blades are assumed...

Suryakumar, Vishvas Samuel

2013-05-02T23:59:59.000Z

246

2-D discrete element modeling of unconsolidated sandstones  

E-Print Network (OSTI)

developed in this thesis is compared to the results of triaxial tests performed in cylindrical core samples of unconsolidated sandstones saturated with heavy oil. The discrete element model treats the sand as a two dimensional assembly of particles...

Franquet Barbara, Javier Alejandro

2012-06-07T23:59:59.000Z

247

Finite-Element Simulation Of Hot-Water-Type Geothermal Reservoirs...  

Open Energy Info (EERE)

the unknown variables of displacement, pore pressure and temperature using an elasto-plastic stress-strain relationship. The mathematical model combines the simultaneous...

248

E-Print Network 3.0 - athena finite elements Sample Search Results  

NLE Websites -- All DOE Office Websites (Extended Search)

at San Diego Collection: Plasma Physics and Fusion 88 Dynamic Modeling and Simulation with ABACUSS II 28th February 2002 Summary: concerned with predicting the...

249

FDM Helmholtz modeling of finite grating and waveguide width effects on resonant subwavelength grating reflectivity.  

SciTech Connect

Resonant subwavelength gratings (RSGs) may be used as narrow-band wavelength and angular reflectors. Rigorous coupled wave analysis (RCWA) predicts 100% reflectivity at the resonant frequency of an incident plane wave from an RSG of infinite extent. For devices of finite extent or for devices illuminated with a finite beam, the peak reflectivity drops, coupled with a broadening of the peak. More complex numerical methods are required to model these finite effects. We have modeled finite devices and finite beams with a two-dimensional finite difference Helmholtz equation. The effect of finite grating aperture and finite beam size are investigated. Specific cases considered include Gaussian beam illumination of an infinite grating, Gaussian illumination of a finite grating, and plane wave illumination of an apertured grating. For a wide grating with a finite Gaussian beam, it is found that the reflectivity is an exponential function of the grating width. Likewise, for an apertured grating the reflectivity shows an exponential decay with narrowing aperture size. Results are compared to other methods, including plane wave decomposition of Gaussian beams using RCWA for the case of a finite input beam, and a semi-analytical techniques for the case of the apertured grating.

Kemme, Shanalyn A.; Peters, David William; Hadley, G. Ronald

2003-07-01T23:59:59.000Z

250

Computer modeling of single-cell and multicell thermionic fuel elements  

SciTech Connect

Modeling efforts are undertaken to perform coupled thermal-hydraulic and thermionic analysis for both single-cell and multicell thermionic fuel elements (TFE). The analysis--and the resulting MCTFE computer code (multicell thermionic fuel element)--is a steady-state finite volume model specifically designed to analyze cylindrical TFEs. It employs an interactive successive overrelaxation solution technique to solve for the temperatures throughout the TFE and a coupled thermionic routine to determine the total TFE performance. The calculated results include temperature distributions in all regions of the TFE, axial interelectrode voltages and current densities, and total TFE electrical output parameters including power, current, and voltage. MCTFE-generated results compare experimental data from the single-cell Topaz-II-type TFE and multicell data from the General Atomics 3H5 TFE to benchmark the accuracy of the code methods.

Dickinson, J.W.; Klein, A.C. [Oregon State Univ., Corvallis, OR (United States). Dept. of Nuclear Engineering

1996-05-01T23:59:59.000Z

251

FEAPpv --A Finite Element Analysis Program Personal Version 3.1 User Manual  

E-Print Network (OSTI)

Department of Civil and Environmental Engineering University of California at Berkeley Berkeley, California.1 Execution of FEAPpv and Input/Output Files. . . . . . . . . . . . . . 4 2.2 Modification of Default Options.6 Plasticity Models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 7.7 Heat Conduction Material

California at Berkeley, University of

252

Deformation Effects in One and Two Chiral Bags Studied with Use of the Finite Element Method  

Science Journals Connector (OSTI)

......Current interest on nuclear forces is focused on...understanding from the sub-nuclear level. With such a motivation...6) with use of low energy effective models of QCD...shown that the lowest energy solu- tion has a doughnut...and the members of his nuclear theory group for their......

Shin-ichi Nawa

1991-08-01T23:59:59.000Z

253

Anisotropic poroelasticity and wave-induced fluid flow: harmonic finite-element simulations  

Science Journals Connector (OSTI)

......decreasing permeability, which is...model Q-(quality factor...obtain the quality factors and...in the reservoir and in the cap rock, where possible...water-saturated Utsira sandstone and low-permeability mudstone...where is the porosity). Also......

J. M. Carcione; J. E. Santos; S. Picotti

2011-09-01T23:59:59.000Z

254

The EM algorithm for the extended finite mixture of the factor analyzers model  

Science Journals Connector (OSTI)

This paper is devoted to extending common factors and categorical variables in the model of a finite mixture of factor analyzers based on the multivariate generalized linear model and the principle of maximum random utility in the probabilistic choice ...

Xingcai Zhou; Xinsheng Liu

2008-04-01T23:59:59.000Z

255

Finite Element Analysis of Indentation in Fiber-Reinforced Polymer Composites  

E-Print Network (OSTI)

indentation tests on the ber of a unidirectional glass/epoxy composite for the strength assessment of its matrix- ber interphase. Their study rested on the assumption that the measured displacement comprises surface indentation and compression components... deformation problem is considered in Chapter II. The indentation load is idealized as a point load. The individual constituents (matrix, in- terphase and ber) of the composite material are modelled as homogeneous, linearly elastic solids whose mechanical...

Ravishankar, Arun

2012-07-16T23:59:59.000Z

256

The inclusion of damage effects in an incremental finite element analysis of composite plates  

E-Print Network (OSTI)

Buckling Patterns for Unidirectional Composites is available describing damage accumulation (damage history) models. Some assume simple reductions of material matrix properties and/or stiffness reductions [27-29]. These reduce particular material pro..., 2) compressive fiber breakage, 3) tensile matrix cracking, 4) compressive matrix cracking, 5) fiber microbuckling, 6) delamination. The Z. Hashin [39] failure criteria is attractive because it separates the failure of a composite laminate...

Kilpatrick, Mark Christopher

1984-01-01T23:59:59.000Z

257

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

258

Calculation of demagnetization curves of NdFeB-magnets using the finite-element-method  

SciTech Connect

A method is developed, which allows to investigate the influence of magnetostatic coupling of structural details on the demagnetization curve within a two dimensional model. In contrast to former methods, which assigned to each grain one value of magnetic field and one value of nucleation field only, this method takes into account the spatial distribution of these fields. It considers not only the coupling between adjacent grains but also the effect of distant grains. The nucleation fields along the boundary of the grains are generated by a statistical method. The magnetic field is calculated by FEM.

Binner, A.; Roth, S.; Stiller, C. [Inst. fuer Festkoerper- und Werkstofforschung Dresden e.V (Germany)] [Inst. fuer Festkoerper- und Werkstofforschung Dresden e.V (Germany)

1994-03-01T23:59:59.000Z

259

Finite-element analysis of the deformation of thin Mylar films due to measurement forces.  

SciTech Connect

Significant deformation of thin films occurs when measuring thickness by mechanical means. This source of measurement error can lead to underestimating film thickness if proper corrections are not made. Analytical solutions exist for Hertzian contact deformation, but these solutions assume relatively large geometries. If the film being measured is thin, the analytical Hertzian assumptions are not appropriate. ANSYS is used to model the contact deformation of a 48 gauge Mylar film under bearing load, supported by a stiffer material. Simulation results are presented and compared to other correction estimates. Ideal, semi-infinite, and constrained properties of the film and the measurement tools are considered.

Baker, Michael Sean; Robinson, Alex Lockwood; Tran, Hy D.

2012-01-01T23:59:59.000Z

260

Discrete-element model for the interaction between ocean waves and sea ice  

SciTech Connect

We present a discrete element method (DEM) model to simulate the mechanical behavior of sea ice in response to ocean waves. The wave/ice interaction can potentially lead to the fracture and fragmentation of sea ice depending on the wave amplitude and period. The fracture behavior of sea ice is explicitly modeled by a DEM method, where sea ice is modeled by densely packed spherical particles with finite size. These particles are bonded together at their contact points through mechanical bonds that can sustain both tensile & compressive forces and moments. Fracturing can be naturally represented by the sequential breaking of mechanical bonds. For a given amplitude and period of incident ocean wave, the model provides information for the spatial distribution and time evolution of stress and micro-fractures and the fragment size distribution. We demonstrate that the fraction of broken bonds,, increases with increasing wave amplitude. In contrast, the ice fragment size decreases with increasing amplitude.

Xu, Zhijie; Tartakovsky, Alexandre M.; Pan, Wenxiao

2012-01-05T23:59:59.000Z

Note: This page contains sample records for the topic "modeling finite element" 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

Experimental and finite-element study of residual stresses in Zircaloy-4(R) and OFHC copper tubes  

SciTech Connect

Nonhomogeneous plastic deformation associated with metal-forming operations results in a state of residual stress in the final product. In the experimental phase of this study, residual stress distribution in Zr-4(R) and copper tubes is determined by electropolishing the outer (or inner) and surface of the tubes while measuring the developed strains at the inner (or outer) surface. Material removal by electropolishing proved to be an efficient and suitable technique due to its constant mass removal rate under conditions which do not alter the patter of residual stresses in the specimen. In the case of Zr-4(R) specimens, experiments were conducted on the as-received (stress relieved) as well as specimens annealed at 500 C for one hour. The effect of various degrees of cold working on the residual stress patterns of drawn copper tubing is determined by performing similar experiments on soft, 1/4-hard, 1/2-hard, and hard temper, OFHC copper specimens. In the second phase of this investigation, an elastic-plastic finite-element code (ABAQUS) is employed in a parametric study to determined the optimum processing conditions for drawing copper tubes.

Rasty, J.

1987-01-01T23:59:59.000Z

262

Acoustic scattering by axisymmertic finite-length bodies with application to fish : measurement and modeling  

E-Print Network (OSTI)

This thesis investigates the complexities of acoustic scattering by finite bodies in general and by fish in particular through the development of an advanced acoustic scattering model and detailed laboratory acoustic ...

Reeder, D. Benjamin (Davis Benjamin), 1966-

2002-01-01T23:59:59.000Z

263

Finite-geometry models of electric field noise from patch potentials in ion traps  

E-Print Network (OSTI)

We model electric field noise from fluctuating patch potentials on conducting surfaces by taking into account the finite geometry of the ion trap electrodes to gain insight into the origin of anomalous heating in ion traps. ...

Low, Guang Hao

264

A posteriori error estimates for mixed finite element and finite volume methods for problems coupled through a boundary with nonmatching grids  

Science Journals Connector (OSTI)

......October 2014 research-article Articles A posteriori error estimates for mixed finite...volume methods for problems coupled through a boundary with nonmatching grids T. Arbogast...adjoining domains sharing boundary conditions on a common boundary interface in the important......

T. Arbogast; D. Estep; B. Sheehan; and S. Tavener

2014-10-01T23:59:59.000Z

265

Experimental and finite element analysis research on cold-formed steel lipped channel beams under web crippling  

Science Journals Connector (OSTI)

Abstract This article presents the results of an investigation into web crippling behavior of cold-formed steel lipped channel beams subjected to end-one-flange (EOF), interior-one-flange (IOF), end-two-flange (ETF), and interior-two-flange (ITF) loading conditions. A total of 48 cold-formed steel lipped channel beams with different boundary conditions, loading conditions, bearing lengths, and section heights were tested. The experimental scheme, failure modes, concentrated load-general vertical deformation and strain intensity distribution curves are presented in the article. The effect of boundary condition, loading condition, bearing length and section height on web crippling ultimate capacity and ductility of cold-formed steel lipped channel beams was also studied. Results of these tests show that the effect of bearing length on the web crippling ultimate capacity in EOF and ETF loading conditions is more obvious than those in IOF and ITF loading conditions. When bearing length is 50, 100, and 150 mm, web crippling ultimate capacity of cold-formed steel lipped channel beams with web slenderness=78 reaches its peak. The middle web enters plasticity and form plastic hinge zone. The values of web crippling ultimate capacity in interior-flange loading conditions are larger than those in end-flange loading conditions. It is shown that the specimens in the interior-flange loading conditions have higher ultimate capacity, larger initial stiffness and better ductility than those of specimens in the end-flange loading conditions. Finite element analysis can simulate experimental failure mode and web crippling ultimate capacity. The calculation equations of web crippling ultimate capacity put forward in the article can accurately predict experimental value.

Yu Chen; Xixiang Chen; Chaoyang Wang

2015-01-01T23:59:59.000Z

266

Generalization of the Atkinson-Wilcox Theorem and the Development of a Novel Scaled Boundary Finite Element Formulation for the Numerical Simulation of Electromagnetic Radiation  

E-Print Network (OSTI)

The Scaled Boundary Finite Element Method is a novel semi-analytical method jointly developed by Chongmin Song and John P Wolf to solve problems in elastodynamics and allied problems in civil engineering. This novel method has been recently reformulated for the following categories of problems in electromagnetics: (1) Determination of Eigen values of metallic cavity structures, 2) Full wave analysis of Shielded micro-strip transmission line structures, and Very Large Scale Integrated Circuit (VLSI) interconnects, and 3) Full wave analysis of periodic structures. In this paper, a novel Scaled Boundary Finite Element formulation is developed for the numerical simulation of the time harmonic electromagnetic radiation in free space from metallic structures of arbitrary shape. The development of the novel formulation necessitates the generalization of the familiar Atkinson-Wilcox radiation series expansion so as to be applicable for arbitrary boundary circumscribing the source of radiation.

Rajan, V S P

2006-01-01T23:59:59.000Z

267

Some Ising model related results for certain subshifts of finite type  

E-Print Network (OSTI)

Some Ising model related results for certain subshifts of finite type Mattias Wallerstedt \\Lambda, Sweden, mattias@math.chalmers.se i #12; Abstract We generalise some results for the Ising model on nonamenable graphs 18 5 Large deviation results 21 6 References 31 iv #12; 1 Introduction The Ising model

Patriksson, Michael

268

A FINITE-VOLUME VERSION OF AIZENMAN-HIGUCHI THEOREM FOR THE 2D ISING MODEL  

E-Print Network (OSTI)

A FINITE-VOLUME VERSION OF AIZENMAN-HIGUCHI THEOREM FOR THE 2D ISING MODEL LOREN COQUILLE AND YVAN-neighbor Ising model at inverse temperature 0 are of the form µ+ + (1 - )µ- , where µ+ and µ- are the two-neighbor ferromagnetic (2d n.n.f.) Ising model, with boundary condition and at inverse temperature 0

Velenik, Yvan

269

A weighted reverse Cuthill-McKee procedure for finite element method algorithms to solve strongly anisotropic electrodynamic problems  

SciTech Connect

This paper presents a technique for improving the convergence rate of a generalized minimum residual (GMRES) algorithm applied for the solution of a algebraic system produced by the discretization of an electrodynamic problem with a tensorial electrical conductivity. The electrodynamic solver considered in this work is a part of a magnetohydrodynamic (MHD) code in the low magnetic Reynolds number approximation. The code has been developed for the analysis of MHD interaction during the re-entry phase of a space vehicle. This application is a promising technique intensively investigated for the shock mitigation and the vehicle control in the higher layers of a planetary atmosphere. The medium in the considered application is a low density plasma, characterized by a tensorial conductivity. This is a result of the behavior of the free electric charges, which tend to drift in a direction perpendicular both to the electric field and to the magnetic field. In the given approximation, the electrodynamics is described by an elliptical partial differential equation, which is solved by means of a finite element approach. The linear system obtained by discretizing the problem is solved by means of a GMRES iterative method with an incomplete LU factorization threshold preconditioning. The convergence of the solver appears to be strongly affected by the tensorial characteristic of the conductivity. In order to deal with this feature, the bandwidth reduction in the coefficient matrix is considered and a novel technique is proposed and discussed. First, the standard reverse Cuthill-McKee (RCM) procedure has been applied to the problem. Then a modification of the RCM procedure (the weighted RCM procedure, WRCM) has been developed. In the last approach, the reordering is performed taking into account the relation between the mesh geometry and the magnetic field direction. In order to investigate the effectiveness of the methods, two cases are considered. The RCM and WRCM procedures has successfully improved the convergence rate of the GMRES solver. For strong anisotropies, the WRCM procedure appears to have a higher convergence rate. The same behavior is shown when applying the methods to the rebuilding of an hypersonic MHD experiment.

Cristofolini, Andrea; Latini, Chiara; Borghi, Carlo A. [Department of Electrical Engineering, University of Bologna, Viale Risorgimento 2, 40136 Bologna (Italy)

2011-02-01T23:59:59.000Z

270

Indeterminate masses, elements and models in information fusion  

Science Journals Connector (OSTI)

In this paper at the beginning, we make a short history of the logics, from the classical Boolean logic to the most general logic of today neutrosophic logic. We define the general logic space and give the definition of the neutrosophic logic. Then we introduce the indeterminate models in information fusion, which are due either to the existence of some indeterminate elements in the fusion space or to some indeterminate masses. The best approach for dealing with such models is the neutrosophic logic, which is part of neutrosophy. Neutrosophic logic is connected with neutrosophic set and neutrosophic probability and statistics.

Florentin Smarandache

2013-01-01T23:59:59.000Z

271

FINITE GROUPS WITH TWO CONJUGACY CLASSES OF p-ELEMENTS AND RELATED QUESTIONS FOR p-BLOCKS  

E-Print Network (OSTI)

K¨ULSHAMMER, GABRIEL NAVARRO, BENJAMIN SAMBALE, AND PHAM HUU TIEP Abstract. We prove that a finite:01:25 BST Version 2 - Submitted to BLMS #12;2 K¨ULSHAMMER, NAVARRO, SAMBALE, AND TIEP Theorem A can

272

Modeling the Effect of Finite-Rate Hydrogen Diffusion on Porosity Formation in Aluminum Alloys  

E-Print Network (OSTI)

Modeling the Effect of Finite-Rate Hydrogen Diffusion on Porosity Formation in Aluminum Alloys KENT of hydrogen in the melt is developed to predict pore formation during the solidification of aluminum alloys by Lee et al.[3] Recent examples of porosity models for aluminum alloy castings, including the effect

Beckermann, Christoph

273

FINITE VOLUME METHODS FOR UNIDIRECTIONAL DISPERSIVE WAVE MODELS  

E-Print Network (OSTI)

], the BBM equation [4] and Boussinesq systems [11, 40, 8]. All these models assume the wave to be weakly to dispersive unidi- rectional water wave propagation in one space dimension. In particular we consider a KdV-BBM differential equation modeling unidirectional wave propagation. Specifically, we consider the KdV-BBM equation

Paris-Sud XI, Université de

274

Finite-Size Scaling for the Ising Model on the Möbius Strip and the Klein Bottle  

Science Journals Connector (OSTI)

We study the finite-size scaling properties of the Ising model on the Möbius strip and the Klein bottle. The results are compared with those of the Ising model under different boundary conditions, that is, the free, cylindrical, and toroidal boundary conditions. The difference in the magnetization distribution function p(m) for various boundary conditions is discussed in terms of the number of the percolating clusters and the cluster size. We also find interesting aspect-ratio dependence of the value of the Binder parameter at T=Tc for various boundary conditions. We discuss the relation to the finite-size correction calculations for the dimer statistics.

Kazuhisa Kaneda and Yutaka Okabe

2001-03-05T23:59:59.000Z

275

Finite-density effective sigma meson mass in chiral models  

Science Journals Connector (OSTI)

Properties of chirally-invariant models of nuclear matter are calculated with the relativistic Hartree approximation. Our emphasis is on the behavior of the effective ? meson mass. We find that the effective ? mass does not scale with the effective nucleon mass, which in these calculations is proportional to the expectation value of the ? field, i.e., the chiral order parameter. These results suggest that a decrease in the effective ? mass with increasing nucleon density is not a generic feature of chiral models. We also find that the incompressibility of nuclear matter is lower for those models with higher effective ? masses.

David K. Griegel and Thomas D. Cohen

1989-03-01T23:59:59.000Z

276

Building relativistic mean field models for finite nuclei and neutron stars  

E-Print Network (OSTI)

Background: Theoretical approaches based on density functional theory provide the only tractable method to incorporate the wide range of densities and isospin asymmetries required to describe finite nuclei, infinite nuclear matter, and neutron stars. Purpose: A relativistic energy density functional (EDF) is developed to address the complexity of such diverse nuclear systems. Moreover, a statistical perspective is adopted to describe the information content of various physical observables. Methods: We implement the model optimization by minimizing a suitably constructed chi-square objective function using various properties of finite nuclei and neutron stars. The minimization is then supplemented by a covariance analysis that includes both uncertainty estimates and correlation coefficients. Results: A new model, FSUGold2, is created that can well reproduce the ground-state properties of finite nuclei, their monopole response, and that accounts for the maximum neutron star mass observed up to date. In particul...

Chen, Wei-Chia

2014-01-01T23:59:59.000Z

277

Massively Parallel Spectral Element Large Eddy Simulation of a Turbulent Channel Using Wall Models  

E-Print Network (OSTI)

the strength and ability to push forward and succeed. I owe you guys everything and nobody could ask for a better family. I love you all. iv NOMENCLATURE CFD Computational Fluid Dynamics DNS Direct Numerical Simulation RANS Reynolds Averaged Navier...-Stokes LES Large Eddy Simulation FEM Finite Element Method SEM Spectral Element Method SGS Sub-Grid Scale TLM Two Layer Method Re Reynolds Number Re Friction Reynolds Number U1 Characteristic Velocity GLL Gauss-Lobatto-Legendre Cs Smagorinski Coe...

Rabau, Joshua I

2013-05-01T23:59:59.000Z

278

Solution of Nonlinear Rational Expectations Models with Applications toFinite-Horizon Life-Cycle Models of Consumption  

Science Journals Connector (OSTI)

This paper considers the solution of nonlinear rational expectations models resulting from the optimality conditions of a finite-horizon intertemporal optimization problem satisfying Bellman's principle of optimality (and possibly involving inequality ... Keywords: exact and certainty-equivalent solutions, intertemporal consumer choice, minimum weighted residual method, nonlinear rational expectations models

Michael Binder; M. Hashem Pesaran; S. Hossein Samiei

2000-04-01T23:59:59.000Z

279

Enforcing elemental mass and energy balances for reduced order models  

SciTech Connect

Development of economically feasible gasification and carbon capture, utilization and storage (CCUS) technologies requires a variety of software tools to optimize the designs of not only the key devices involved (e., g., gasifier, CO{sub 2} adsorber) but also the entire power generation system. High-fidelity models such as Computational Fluid Dynamics (CFD) models are capable of accurately simulating the detailed flow dynamics, heat transfer, and chemistry inside the key devices. However, the integration of CFD models within steady-state process simulators, and subsequent optimization of the integrated system, still presents significant challenges due to the scale differences in both time and length, as well the high computational cost. A reduced order model (ROM) generated from a high-fidelity model can serve as a bridge between the models of different scales. While high-fidelity models are built upon the principles of mass, momentum, and energy conservations, ROMs are usually developed based on regression-type equations and hence their predictions may violate the mass and energy conservation laws. A high-fidelity model may also have the mass and energy balance problem if it is not tightly converged. Conservations of mass and energy are important when a ROM is integrated to a flowsheet for the process simulation of the entire chemical or power generation system, especially when recycle streams are connected to the modeled device. As a part of the Carbon Capture Simulation Initiative (CCSI) project supported by the U.S. Department of Energy, we developed a software framework for generating ROMs from CFD simulations and integrating them with Process Modeling Environments (PMEs) for system-wide optimization. This paper presents a method to correct the results of a high-fidelity model or a ROM such that the elemental mass and energy are conserved perfectly. Correction factors for the flow rates of individual species in the product streams are solved using a minimization algorithm based on Lagrangian multiplier method. Enthalpies of product streams are also modified to enforce the energy balance. The approach is illustrated for two ROMs, one based on a CFD model of an entrained-flow gasifier and the other based on the CFD model of a multiphase CO{sub 2} adsorber.

Ma, J.; Agarwal, K.; Sharma, P.; Lang, Y.; Zitney, S.; Gorton, I.; Agawal, D.; Miller, D.

2012-01-01T23:59:59.000Z

280

Three-dimensional finite difference time domain modeling of the Schumann resonance  

E-Print Network (OSTI)

Three-dimensional finite difference time domain modeling of the Schumann resonance parameters to as Schumann resonances and are excited by lightning discharges. The detection of such resonances on other frequency propagation is employed to study the Schumann resonance problems on Titan, Venus, and Mars

Pasko, Victor

Note: This page contains sample records for the topic "modeling finite element" 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

Meson properties in a nonlocal SU(3) chiral quark model at finite temperature  

SciTech Connect

Finite temperature meson properties are studied in the context of a nonlocal SU(3) quark model which includes flavor mixing and the coupling of quarks to the Polyakov loop (PL). We analyze the behavior of scalar and pseudoscalar meson masses and mixing angles, as well as quark-meson couplings and pseudoscalar meson decay constants.

Contrera, G. A. [CONICET, Rivadavia 1917, 1033 Buenos Aires (Argentina); Physics Department, Centro Atomico Constituyentes, Buenos Aires (Argentina); Gomez Dumm, D. [CONICET, Rivadavia 1917, 1033 Buenos Aires (Argentina); IFLP, Dpto. de Fisica, Universidad Nacional de La Plata, C.C. 67, (1900) La Plata (Argentina); Scoccola, N. N. [CONICET, Rivadavia 1917, 1033 Buenos Aires (Argentina); Universidad Favaloro, Solis 453, 1078 Buenos Aires (Argentina)

2010-11-12T23:59:59.000Z

282

FINITE VOLUME METHODS FOR UNIDIRECTIONAL DISPERSIVE WAVE MODELS  

E-Print Network (OSTI)

V95], the BBM equation [BBM72] and Boussinesq systems [Bou72, Per67, BCS02]. All these models as- sume to dispersive unidi- rectional water wave propagation in one space dimension. In particular we consider a KdV-BBM the KdV-BBM equation in its general form: ut + ux + uux - uxxt + uxxx = 0, (1.1) for x R, t > 0

Paris-Sud XI, Université de

283

Thermodynamics and fluctuations of conserved charges in Hadron Resonance Gas model in finite volume  

E-Print Network (OSTI)

The thermodynamics of hot and dense matter created in heavy-ion collision experiments are usually studied as a system of infinite volume. Here we report on possible effects for considering a finite system size for such matter in the framework of the Hadron Resonance Gas model. The bulk thermodynamic variables as well as the fluctuations of conserved charges are considered. We find that the finite size effects are insignificant once the observables are scaled with the respective volumes. The only substantial effect is found in the fluctuations of electric charge which may therefore be used to extract information about the volume of fireball created in heavy-ion collision experiments.

Bhattacharyya, Abhijit; Samanta, Subhasis; Sur, Subrata

2015-01-01T23:59:59.000Z

284

Structure of finite-RSB asymptotic Gibbs measures in the diluted spin glass models  

E-Print Network (OSTI)

We suggest a possible approach to proving the M\\'ezard-Parisi formula for the free energy in the diluted spin glass models, such as diluted K-spin or random K-sat model at any positive temperature. In the main contribution of the paper, we show that a certain small modification of the Hamiltonian in any of these models forces all finite-RSB asymptotic Gibbs measures in the sense of the overlaps to satisfy the M\\'ezard-Parisi ansatz for the distribution of spins. Unfortunately, what is still missing is a description of the general full-RSB asymptotic Gibbs measures. If one could show that the general case can be approximated by finite-RSB case in the right sense then one could a posteriori remove the small modification of the Hamiltonian to recover the M\\'ezard-Parisi formula for the original model.

Dmitry Panchenko

2014-06-18T23:59:59.000Z

285

Distributed three-dimensional finite-difference modeling of wave propagation in acoustic media  

Science Journals Connector (OSTI)

Finite-difference modeling of wave propagation in heterogeneous media is a useful technique in a number of disciplines including earthquake and oil exploration seismology laboratory ultrasonics ocean acoustics radar imaging nondestructive evaluation and others. However the size of the models that can be treated by finite-difference methods in three spatial dimensions has limited their application to supercomputers. We describe a finite-difference domain-decomposition method for the three-dimensional acoustic wave equation which is well suited to distributed parallelization. We have implemented this algorithm using the PVM message-passing library and show here benchmarks on two different distributed memory architectures the IBM SP2 and a network of low-cost PCs running the Linux operating system. We present performance measurements of this algorithm on both the low-bandwidth PC network (10-Mbits/s Ethernet) and the high-bandwidth SP2 cluster (40-Mbits/s switch). These results demonstrate the feasibility of doing distributed finite-difference acoustic modeling on networks of workstations but point to the substantial efficiencies that can be expected as higher bandwidth networks become available. © 1997 American Institute of Physics.

Alberto Villarreal

1997-01-01T23:59:59.000Z

286

CP(N-1) model on finite interval in the large N limit  

E-Print Network (OSTI)

The CP(N-1) \\sigma\\ model on finite interval of length R with Dirichlet boundary conditions is analysed in the 1/N expansion. The theory has two phases, separated by a phase transition at R ~ 1/\\Lambda, \\Lambda\\ is dynamical scale of the CP(N-1) model. The vacuum energy dependence of R, and especially Casimir-type scaling 1/R, is discussed.

A. Milekhin

2012-07-02T23:59:59.000Z

287

Quark matter and meson properties in a Nonlocal SU(3) chiral quark model at finite temperature  

SciTech Connect

We study the finite temperature behavior of light scalar and pseudoscalar meson properties in the context of a three-flavor nonlocal chiral quark model. The model includes mixing with active strangeness degrees of freedom, and takes care of the effect of gauge interactions by coupling the quarks with a background color field. We analyze the chiral restoration and deconfinement transitions, as well as the temperature dependence of meson masses, mixing angles, and decay constants.

Gomez Dumm, D., E-mail: dumm@fisica.unlp.edu.ar [UNLP, IFLP, Departamento de Fisica (Argentina); Contrera, G. A., E-mail: contrera@tandar.cnea.gov.ar [CONICET (Argentina)

2012-06-15T23:59:59.000Z

288

One Time-step Finite Element Discretization of the Equation of Motion of Two-fluid Flows  

E-Print Network (OSTI)

at the boundary and at the interface between the two fluids. We discretize this system with the "mini boundary; "mini-element" INTRODUCTION This work is devoted to the numerical solution of the equations, an Arbitrary Lagrangian-Eulerian method of approximation (ALE), which is based on a grid that moves

Maury, Bertrand

289

Building relativistic mean field models for finite nuclei and neutron stars  

E-Print Network (OSTI)

Background: Theoretical approaches based on density functional theory provide the only tractable method to incorporate the wide range of densities and isospin asymmetries required to describe finite nuclei, infinite nuclear matter, and neutron stars. Purpose: A relativistic energy density functional (EDF) is developed to address the complexity of such diverse nuclear systems. Moreover, a statistical perspective is adopted to describe the information content of various physical observables. Methods: We implement the model optimization by minimizing a suitably constructed chi-square objective function using various properties of finite nuclei and neutron stars. The minimization is then supplemented by a covariance analysis that includes both uncertainty estimates and correlation coefficients. Results: A new model, FSUGold2, is created that can well reproduce the ground-state properties of finite nuclei, their monopole response, and that accounts for the maximum neutron star mass observed up to date. In particular, the model predicts both a stiff symmetry energy and a soft equation of state for symmetric nuclear matter--suggesting a fairly large neutron-skin thickness in Pb208 and a moderate value of the nuclear incompressibility. Conclusions: We conclude that without any meaningful constraint on the isovector sector, relativistic EDFs will continue to predict significantly large neutron skins. However, the calibration scheme adopted here is flexible enough to create models with different assumptions on various observables. Such a scheme--properly supplemented by a covariance analysis--provides a powerful tool to identify the critical measurements required to place meaningful constraints on theoretical models.

Wei-Chia Chen; J. Piekarewicz

2014-08-18T23:59:59.000Z

290

Finite-element method simulation of effects of microstructure, stress state, and interface strength on flow localization and constraint development in Nb/Cr{sub 2}Nb in situ composites  

SciTech Connect

The effects of volume fraction of particles, stress state, and interface strength on the yield strength, flow localization, plastic constraint, and damage development in Nb/Cr{sub 2}Nb in situ composites were investigated by the finite-element method (FEM). The microstructure of the in situ composite was represented in terms of a unit rectangular or square cell containing Cr{sub 2}Nb particles embedded within a solid-solution-alloy matrix. The hard particles were considered to be elastic and isotropic, while the matrix was elastic-plastic, obeying the Ramberg-Osgood constitutive relation. The FEM model was utilized to compute the composite strength, local hydrostatic stress, and plastic strain distributions as functions of volume fraction of particles, stress state, and interface strength. The results were used to elucidate the influence of volume fracture of particles, stress state, and interface property on the development of plastic constraint and damage in Nb/Cr{sub 2}Nb composites.

Lin, G.; Chan, K.S.

1999-12-01T23:59:59.000Z

291

Development of fatigue stress spectrum and fatigue life prediction of endless winder sheave for wind turbine lift using finite element analysis  

Science Journals Connector (OSTI)

This paper aims to develop the fatigue stress spectrum and predicted fatigue life of the endless winder sheave using finite element (FE) analysis which is utilized in wind turbine lift. First we identified the fatigue critical location (FCL) of endless winder sheave through a static FE analysis. And the lifting velocity was measured using the non-contact velocity dectector. Based on the measured lifting velocity and compressive loads by traction of endless winder sheave the compressive load-angle of rotation history at the FCL was determined. According to the compressive load-angle of rotation time history total 230 FE analyses were performed with the interval of the angle of rotation of 15° we eventually obtained the fatigue stress spectrum at the FCL. These results were processed using the rainflow cycle counting and the Goodman equation. Finally the fatigue life of sheave was evaluated using the linear damage cumulative rule.

2014-01-01T23:59:59.000Z

292

Studying fast wave propagation and absorption at any cyclotron harmonic using a 2D finite element area coordinates wave equation solver  

SciTech Connect

Fourier analysis in the poloidal direction is a standard ingredient in present-day 2D wave equation solvers describing radio frequency waves in hot tokamak plasmas. Although a powerful and elegant technique, Fourier analysis has the disadvantage that a large number of modes is needed to describe the field pattern on a magnetic surface if a short wavelength mode exists on any - even very small - subpart of the particle trajectory. The present paper examines the potential of a method that does not suffer from this drawback: a finite element technique relying on simple linear or cubic area base functions that are defined on irregular elementary surfaces of triangular shape. The wave equation is solved in its weak Galerkin variational form and for realistic 2D tokamak geometry, accounting for the toroidal curvature but assuming the toroidal angle is ignorable, allowing to study the wave pattern for each of the independent toroidal modes excited by the antenna individually.The locally uniform full hot plasma dielectric tensor to all orders in finite Larmor radius was adopted. As the main intended application is the study of fast wave behavior (heating and current drive) at arbitrary harmonics, the wave vector complex amplitude appearing in the dielectric tensor is determined through a local dispersion root evaluation. High frequency fast wave propagation and damping is provided as an illustration in view of possible application of this type of current drive in future high density reactor-like tokamaks.

Lerche, Ernesto; Van Eester, Dirk [LPP-ERM/KMS, Association Euratom-'Belgian State', TEC Partner, Brussels (Belgium)

2011-12-23T23:59:59.000Z

293

Proper orthogonal decomposition approach and error estimation of mixed finite element methods for the tropical Pacific Ocean  

E-Print Network (OSTI)

for the tropical Pacific Ocean reduced gravity model Zhendong Luo a , Jiang Zhu b , Ruiwen Wang b , I.M. Navon c Available online 8 May 2007 Abstract In this paper, the tropical Pacific Ocean reduced gravity model and the insufficient knowledge of air­sea exchange processes. The tropical Pacific Ocean reduced gravity model

Navon, Michael

294

Dynamics of strong-coupling models for cuprate superconductors: Exact results on finite lattices  

SciTech Connect

We discuss recent applications of exact numerical continued fraction expansion (CFE) techniques to calculate dynamical correlation functions of various strong-coupling models related to the high-temperature cuprate superconductors. For the two-dimensional square-lattice spin-1/2 Heisenberg antiferromagnet, we present exact results for the zero-temperature dynamical structure factor on finite-sized lattices and compare them to approximate results from a Schwinger boson mean-field theory, recently proposed by Arovas and Auerbach. We find that the mean-field theory represents a very good approximation to the exact spin excitation spectra and to the static spin correlations. We then investigation the dynamical spin-spin structure factor and the single-particle spectral function for finite model clusters with dopant induced hole-type charge carriers, in the strong-coupling limit of both the single-band Hubbard model (t-J-model) and the three-band Hubbard model (Kondo-Heisenberg model). Our results are consistent with the physical picture recently proposed by Zhang and Rice which implies an approximate mapping of the low-energy states in the three-band model onto an effective single-band theory. 33 refs., 4 figs.

Schuettler, H.B.; Chen, C.-X. (Georgia Univ., Athens, GA (USA). Center for Simulational Physics); Fedro, A.J. (Argonne National Lab., IL (USA) Northern Illinois Univ., Dekalb, IL (USA). Dept. of Physics)

1989-01-01T23:59:59.000Z

295

Modeling a solar energy collector with an integrated phase-change material  

E-Print Network (OSTI)

In this thesis, a finite-element computer model was created to simulate a solar air heater with an integrated-phase change material. The commercially available finite element package ADINA-Fluid was used to generate the ...

Guerra, Alexander Adrian

2009-01-01T23:59:59.000Z

296

Modeling a solar energy collector with an integrated phase-change material .  

E-Print Network (OSTI)

??In this thesis, a finite-element computer model was created to simulate a solar air heater with an integrated-phase change material. The commercially available finite element… (more)

Guerra, Alexander Adrian

2009-01-01T23:59:59.000Z

297

Numerical simulations and predictive models of undrained penetration in soft soils  

E-Print Network (OSTI)

of rateindependent finite element analyses of pre-embedded penetration depths, and validate the results by upper and lower bound solutions from classical plasticity theory. Furthermore, strain rate effects are modeled by finite element simulations within a framework...

Shi, Han

2005-11-01T23:59:59.000Z

298

Failure analysis of reinforced polyurethane foam-based LNG insulation structure using damage-coupled finite element analysis  

Science Journals Connector (OSTI)

Abstract The primary aim of this study was to develop a unified anisotropic elasto-viscoplastic-damage model that describes the material nonlinear behavior and damage/crack growth of a reinforced polyurethane foam-based liquefied natural gas carrier insulation system. A Bodner–Partom unified elasto-viscoplastic model independent of the yield surface and loading history was expanded to an anisotropic unified model. To predict the damage growth and the crack initiation/growth of reinforced polyurethane foam, a Bodner–Chan damage model was applied to the proposed unified elasto-viscoplastic-damage model. The developed mechanical model was implicitly formulated and implemented into an ABAQUS user-defined material subroutine. To validate the proposed numerical method, the simulation results were compared with the results of a series of static uniaxial tests and dynamic cyclic tests conducted on the reinforced polyurethane foam and the liquefied natural gas carrier insulation system, respectively.

Chi-Seung Lee; Jae-Myung Lee

2014-01-01T23:59:59.000Z

299

Simulation Research on Switched Reluctance Motor Modeling and Control Strategy Based on ANSOFT  

Science Journals Connector (OSTI)

Based on ANSOFT software, the 2d and 3d finite element models of switch reluctance motor were established, the dynamic simulations on the switch reluctance motor finite element models were researched by different control strategies. The accuracy and ... Keywords: SRM, Ansoft, the finite element, simulation

Yuelun Ling; Mianhua Wang; Yan Wang; Fenli Wang

2010-03-01T23:59:59.000Z

300

Elements & Compounds Atoms (Elements)  

E-Print Network (OSTI)

#12;Elements & Compounds #12;Atoms (Elements) Molecules (Compounds) Cells Elements & Compounds #12;Nucleus Electrons Cloud of negative charge (2 electrons) Fig. 2.5: Simplified model of a Helium (He) Atom He 4.002602 2 Helium Mass Number (~atomic mass) = number of Neutrons + Protons = 4 for Helium Atomic

Frey, Terry

Note: This page contains sample records for the topic "modeling finite element" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
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to obtain the most current and comprehensive results.


301

Shell model nuclear matrix elements for competing mechanisms contributing to double beta decay  

SciTech Connect

Recent progress in the shell model approach to the nuclear matrix elements for the double beta decay process are presented. This includes nuclear matrix elements for competing mechanisms to neutrionless double beta decay, a comparison between closure and non-closure approximation for {sup 48}Ca, and an updated shell model analysis of nuclear matrix elements for the double beta decay of {sup 136}Xe.

Horoi, Mihai [Department of Physics, Central Michigan University, Mount Pleasant, Michigan, 48859 (United States)

2013-12-30T23:59:59.000Z

302

Finite Element Procedures for 2D and 3D Seismoelectric Modeling  

E-Print Network (OSTI)

Por favor si te parece esto bien, hace el laburo de estimar la constante C8 ya que la necesitamos, quedara seguro en funcion de las cotas de los coeficientes de ...

303

A finite element model of the turbulent flow field in a centrifugal impeller  

E-Print Network (OSTI)

' ? + ? ? ' ? j+ WTi aNi aNj 1 aNi aNj ? aNj p '" a" r2ae ae + ? Wit NI ? ] d(dq aNj 'ae (28) I +I B2 jj: 2 [ J ( S2 NI Nj d( dq -I -I (29) +I +I ? I J IN; dgdq aMk (3o) +I +I Ct Ij = 2l JIQNjNj dgdq -I -I (31) ~ I ~ I C&, ;&= ~IJIN; ae (32) +I... ' ? + ? ? ' ? j+ WTi aNi aNj 1 aNi aNj ? aNj p '" a" r2ae ae + ? Wit NI ? ] d(dq aNj 'ae (28) I +I B2 jj: 2 [ J ( S2 NI Nj d( dq -I -I (29) +I +I ? I J IN; dgdq aMk (3o) +I +I Ct Ij = 2l JIQNjNj dgdq -I -I (31) ~ I ~ I C&, ;&= ~IJIN; ae (32) +I...

Hlavaty, Steven Todd

2012-06-07T23:59:59.000Z

304

Decoupled Modeling of Chilled Water Cooling Coils Using a Finite Element Method  

E-Print Network (OSTI)

&M University Abstract Chilled water cooling coils are important components in air handling unit systems. Generally the cooling coil removes both moisture and sensible heat from entering air. Since the sensible and latent heat transfer modes are coupled... and the saturation humidity ratio vs. temperature curve on the psychrometric chart is non-linear, it is very difficult to solve cooling coil heat transfer differential equations across the entire coil. However, the sensible and latent heat transfer modes can...

Wang, G.; Liu, M.

2005-01-01T23:59:59.000Z

305

An hp finite element adaptive scheme to solve the Laplace model for fluid-solid vibrations  

E-Print Network (OSTI)

Exactas y Naturales, Universidad de Buenos Aires, 1428, Buenos Aires, Argentina b Centro At´omico Bariloche, 4800, Bariloche, Argentina c CI2 MA, Departamento de Ingenier´ia Matem´atica, Universidad de. We show its reliability and efficiency by proving that the estimator is equivalent to the energy norm

Armentano, María Gabriela

306

Finite-element harmonic experiments to model fractured induced anisotropy in  

E-Print Network (OSTI)

, Argentina. cUniversidad Nacional de La Plata, La Plata, Argentina. dIstituto Nazionale di Oceanografia e di problems, and derive optimal a priori energy error estimates. First, the numerical results are validated

Santos, Juan

307

Preliminary finite element modeling of a piezoelectric actuated marine propulsion fin.  

E-Print Network (OSTI)

??New technologies surrounding composite materials and autonomous underwater vehicle (AUV) design have led to numerous studies involving the marine propulsion for these AUVs. AUVs traditionally… (more)

Streett, Andrew

2006-01-01T23:59:59.000Z

308

Preliminary Finite Element Modeling of a Piezoelectric Actuated Marine Propulsion Fin.  

E-Print Network (OSTI)

?? New technologies surrounding composite materials and autonomous underwater vehicle (AUV) design have led to numerous studies involving the marine propulsion for these AUVs. AUVs… (more)

Streett, Andrew R.

2006-01-01T23:59:59.000Z

309

Mechanical testing of bones: the positive synergy of finite–element models and in vitro experiments  

Science Journals Connector (OSTI)

...loading, but not from a traumatic event; Jeffery 1974; Rockwood et al. 1991), then...pp. 211-234. New York, NY: ASME. Jeffery, C. C. 1974 Spontaneous fractures of...00003086-200212000-00037 ) Szivek, J. A. , J. B. Benjamin, and P. L. Anderson 2000 An experimental...

2010-01-01T23:59:59.000Z

310

k - Version of Finite Element Method for Polymer flows using Giesekus Constitutive Model  

E-Print Network (OSTI)

. It is shown that in the hpk framework when hd goes to 0 and k goes to infinity, physics is approached where the lid meets the stationary vertical walls. Various numerical studies are presented upto deborah number of 2.4 for hd = 0.1 and 0.05. The converged...

Deshpande, Kedar M.

2008-01-31T23:59:59.000Z

311

Finite element modeling of the RAH-66 Comanche Helicopter Tailcone section using PATRAN and DYTRAN .  

E-Print Network (OSTI)

??The United States Army contracted Boeing-Sikorsky to develop the RAH-66 Comanche, a new, armed reconnaissance helicopter that features stealth technology designed to improve survivability when… (more)

Libby, Jeffrey A.

2001-01-01T23:59:59.000Z

312

Ionic Polymer-Metal Composites: Thermodynamical Modeling and Finite Element Solution  

E-Print Network (OSTI)

equations and the transient response of q and C1 are obtained (as shown in appendix A). Mechanical equilibrium equation for the beam is given by EI(v00000 + kC 00 1 ) = w (2.14) along with the natural and essential boundary conditions (EI(v000 + kC1...) M) _v00jx=0 = 0; (EI(v000 + kC1) M) _v00jx=L = 0 (EI(v0000 + kC 0 1) F ) _v0jx=0 = 0; (EI(v0000 + kC 01) F ) _v0jx=L = 0 (2.15) At a given cross section of the beam R _q + S _C1 = V q p DIC1 (2.16) Q _C1 + S _q = EIkv000 (BI + EIk2)C1...

Arumugam, Jayavel

2012-10-19T23:59:59.000Z

313

Thermo-Poroelastic Modeling of Reservoir Stimulation and Microseismicity Using Finite Element Method with Damage Mechanics  

E-Print Network (OSTI)

Stress and permeability variations around a wellbore and in the reservoir are of much interest in petroleum and geothermal reservoir development. Water injection causes significant changes in pore pressure, temperature, and stress in hot reservoirs...

Lee, Sang Hoon

2012-02-14T23:59:59.000Z

314

Investigation of Primary Blast Injury and Protection using Sagittal and Transverse Finite Element Head Models.  

E-Print Network (OSTI)

??The prevalence of blast related mild traumatic brain injury (mTBI) in recent military conflicts, attributed in part to an increased exposure to improvised explosive devices… (more)

Singh, Dilaver

2015-01-01T23:59:59.000Z

315

Quantification of cellular penetrative forces using lab-on-a-chip technology and finite element modeling  

Science Journals Connector (OSTI)

...with both mechanisms and hence does not allow discrimination between...shown that an increase in turgor does not cause a change in tube diameter...Biology 1 ( 1 ): 96 – 113 . 23 Erbar C ( 2003 ) Pollen tube transmitting tissue...1621 – 1631 . 34 astrom H Sorri O Raudaskoski M ( 1995 ) Role of microtubules...

Amir Sanati Nezhad; Mahsa Naghavi; Muthukumaran Packirisamy; Rama Bhat; Anja Geitmann

2013-01-01T23:59:59.000Z

316

Adaptive finite element modelling of two-dimensional magnetotelluric fields in general anisotropic media  

Science Journals Connector (OSTI)

......the error indicator is updated. This process is repeated until the required level of...after 16 grid refinement and the iteration process was terminated. The final mesh contains...induction problem, 71th Annual Internat. Mtg., Soc. Expl. Geophys. (Expanded......

Yuguo Li; Josef Pek

2008-12-01T23:59:59.000Z

317

Multiscale modelling and nonlinear finite element analysis as clinical tools for the assessment of fracture risk  

Science Journals Connector (OSTI)

...accurately predict fracture risk they must also account for age...monitoring the long-term fracture risk of-patients. 6. The multiscale...approach to predict fracture risk is to combine accurate loading...resolving bone microstructure in acceptable amounts of time and computer...

2010-01-01T23:59:59.000Z

318

A parallel finite-element method for three-dimensional controlled-source electromagnetic forward modelling  

Science Journals Connector (OSTI)

......of classical QMR), but have minimal storage requirements. A variation of QMR for...of them do not require computation and storage. The construction of this pre-conditioner...geometry: two half-spaces that represent seawater (sigma0 = 3.3Sm 1) and sediments......

Vladimir Puzyrev; Jelena Koldan; Josep de la Puente; Guillaume Houzeaux; Mariano Vázquez; José María Cela

2013-01-01T23:59:59.000Z

319

Detecting and modeling cement failure in high pressure/ high temperature wells using finite-element method  

E-Print Network (OSTI)

. In the event that high-pressure and high-temperature (HPHT) conditions are encountered, we must attempt to achieve permeability in the set cement to prevent gas migration and to prevent any other fluid passing through to collapse the entire structure. Therefore...

Shahri, Mehdi Abbaszadeh

2006-04-12T23:59:59.000Z

320

3D Contact Finite Element Simulation of the Automobile Gasoline Economizer of the One-way Gear Device  

Science Journals Connector (OSTI)

Automobile gasoline economizer of the one-way gear device is a simple, effective and low cost saving device, which consists of inside core, pawl and outer ratchet. The 3d contact model is established on the base of elastic contact theory and then the ... Keywords: gear devices, contact stress, contact strain, FEA, automobile gasoline economizer

Yanxia Wang; Shanliang Sun; Hui Gao

2010-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling finite element" 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

Parallel, Multigrid Finite Element Simulator for Fractured/Faulted and Other Complex Reservoirs based on Common Component Architecture (CCA)  

SciTech Connect

Black-oil, compositional and thermal simulators have been developed to address different physical processes in reservoir simulation. A number of different types of discretization methods have also been proposed to address issues related to representing the complex reservoir geometry. These methods are more significant for fractured reservoirs where the geometry can be particularly challenging. In this project, a general modular framework for reservoir simulation was developed, wherein the physical models were efficiently decoupled from the discretization methods. This made it possible to couple any discretization method with different physical models. Oil characterization methods are becoming increasingly sophisticated, and it is possible to construct geologically constrained models of faulted/fractured reservoirs. Discrete Fracture Network (DFN) simulation provides the option of performing multiphase calculations on spatially explicit, geologically feasible fracture sets. Multiphase DFN simulations of and sensitivity studies on a wide variety of fracture networks created using fracture creation/simulation programs was undertaken in the first part of this project. This involved creating interfaces to seamlessly convert the fracture characterization information into simulator input, grid the complex geometry, perform the simulations, and analyze and visualize results. Benchmarking and comparison with conventional simulators was also a component of this work. After demonstration of the fact that multiphase simulations can be carried out on complex fracture networks, quantitative effects of the heterogeneity of fracture properties were evaluated. Reservoirs are populated with fractures of several different scales and properties. A multiscale fracture modeling study was undertaken and the effects of heterogeneity and storage on water displacement dynamics in fractured basements were investigated. In gravity-dominated systems, more oil could be recovered at a given pore volume of injection at lower rates. However, if oil production can be continued at high water cuts, the discounted cumulative production usually favors higher production rates. The workflow developed during the project was also used to perform multiphase simulations in heterogeneous, fracture-matrix systems. Compositional and thermal-compositional simulators were developed for fractured reservoirs using the generalized framework. The thermal-compositional simulator was based on a novel 'equation-alignment' approach that helped choose the correct variables to solve depending on the number of phases present and the prescribed component partitioning. The simulators were used in steamflooding and in insitu combustion applications. The framework was constructed to be inherently parallel. The partitioning routines employed in the framework allowed generalized partitioning on highly complex fractured reservoirs and in instances when wells (incorporated in these models as line sources) were divided between two or more processors.

Milind Deo; Chung-Kan Huang; Huabing Wang

2008-08-31T23:59:59.000Z

322

Computational upscaled modeling of heterogeneous porous media flow utilizing finite volume method  

E-Print Network (OSTI)

-Gupta (Member) Al Boggess (Head of Department) May 2004 Major Subject: Mathematics iii ABSTRACT Computational Upscaled Modeling of Heterogeneous Porous Media Flow Utilizing Finite Volume Method. (May 2004) Victor Eralingga Ginting, B.S., Institute of Technology... of L2 norm of solution error for =h = 0:64, and n = 16. 39 3.6 Comparison of L2 norm of solution error for N = 32. : : : : : : : : : 39 3.7 Results for anisotropic case, lx1 = 0:40, lx2 = 0:01, = 1:0. : : : : : : 41 3.8 Results for anisotropic case...

Ginting, Victor Eralingga

2005-08-29T23:59:59.000Z

323

Finite-geometry models of electric field noise from patch potentials in ion traps  

SciTech Connect

We model electric field noise from fluctuating patch potentials on conducting surfaces by taking into account the finite geometry of the ion trap electrodes to gain insight into the origin of anomalous heating in ion traps. The scaling of anomalous heating rates with surface distance d is obtained for several generic geometries of relevance to current ion trap designs, ranging from planar to spheroidal electrodes. The influence of patch size is studied both by solving Laplace's equation in terms of the appropriate Green's function as well as through an eigenfunction expansion. Scaling with surface distance is found to be highly dependent on the choice of geometry and the relative scale between the spatial extent of the electrode, the ion-electrode distance, and the patch size. Our model generally supports the d{sup -4} dependence currently found by most experiments and models, but also predicts geometry-driven deviations from this trend.

Low, Guang Hao [MIT-Harvard Center for Ultracold Atoms, Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Department of Physics, Cavendish Laboratory, J. J. Thomson Avenue, Cambridge, CB3 0HE (United Kingdom); Herskind, Peter F.; Chuang, Isaac L. [MIT-Harvard Center for Ultracold Atoms, Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

2011-11-15T23:59:59.000Z

324

Supporting material for the paper 'Analysis of an interface stabilised finite element method: The advection-diffusion-reaction equation'  

E-Print Network (OSTI)

compilation of the form parameters.optimize = True # Define boundary of domain class Boundary(SubDomain): def inside(self, x, on_boundary): return on_boundary def solve(mesh, order, model): # Advective velocity V_b = VectorFunctionSpace(mesh, "CG", order+6) b... , V: Constant(V.mesh(), (4.0/5.0, 3.0/5.0)) tmp0 = "(cos((pi*(1+x[0])*(1+x[1])*(1+x[1])/8))*pi*(1+x[1])*(1+x[1])/8)" tmp1 = "(cos((pi*(1+x[0])*(1+x[1])*(1+x[1])/8))*2*pi*(1+x[0])*(1+x[1])/8)" source = "(4.0/5.0)*tmp0 + (3.0/5.0)*tmp1 + 1 + sin((pi*(1+x...

Wells, G N

2009-10-28T23:59:59.000Z

325

Investigation of water and CO2 (carbon dioxide) flooding using micro-CT (micro-computed tomography) images of Berea sandstone core using finite element simulations  

Science Journals Connector (OSTI)

The present study reports a numerical investigation of water and CO2 (carbon dioxide) flooding at the pore scale of a porous medium. We use high resolution micro-computed tomography (micro-CT) images of Berea sandstone core to obtain the pore geometry. The numerical solution used for the simulation was carried out by a finite element based software package. Level Set method is used to determine the position of the interface between two immiscible fluids when oil is displaced by water and CO2, respectively. The present formulation is validated against single-phase flow through the porous structure. It is found that, fluid flow inside the pore space takes place through preferential inlet and outlet pores. For two-phase flow, it is observed that continuous displacement of oil occurs during water flooding but CO2 is able to displace oil at certain locations in the pores. Also, the separation of flow front is observed in the case of CO2 flooding. A quantitative comparison of the results obtained in two types of flooding simulations suggests that water displaces a higher volume of oil than CO2 in the time period for which the simulations are performed.

Akshay C. Gunde; Bijoyendra Bera; Sushanta K. Mitra

2010-01-01T23:59:59.000Z

326

Challenges for a reliable shell model description of the neutrinoless double beta decay matrix elements  

Science Journals Connector (OSTI)

Assuming that the neutrinos are Majorana particles and the neutrinoless double beta (0???) decay is observed a reliable 0??? matrix element is necessary to decide the neutrino mass hierarchy and the minimum neutrino mass. Many nuclear structure techniques including the shell model are presently used to calculate these matrix elements. In the last few years one could see a slow convergence of these results but not yet at a level of 20 several shell model effective interactions and varying other parameters finding results in a range that spans about 20In this contribution we describe challenges for obtaining reliable shell model 0??? matrix elements with emphasis to 76 Ge and 82 Se decays.

2011-01-01T23:59:59.000Z

327

Finite size scaling of the 5D Ising model with free boundary conditions  

E-Print Network (OSTI)

There has been a long running debate on the finite size scaling for the Ising model with free boundary conditions above the upper critical dimension, where the standard picture gives a $L^2$ scaling for the susceptibility and an alternative theory has promoted a $L^{5/2}$ scaling, as would be the case for cyclic boundary. In this paper we present results from simulation of the far largest systems used so far, up to side $L=160$ and find that this data clearly supports the standard scaling. Further we present a discussion of why rigorous results for the random-cluster model provides both supports the standard scaling picture and provides a clear explanation of why the scalings for free and cyclic boundary should be different.

Lundow, P H

2014-01-01T23:59:59.000Z

328

The Casimir force on a piston at finite temperature in Randall-Sundrum models  

E-Print Network (OSTI)

The Casimir effect for a three-parallel-plate system at finite temperature within the frame of five-dimensional Randall-Sundrum models is studied. In the case of Randall-Sundrum model involving two branes we find that the Casimir force depends on the plates distance and temperature after one outer plate has been moved to the distant place. Further we discover that the sign of the reduced force is negative as the plate and piston locate very close, but the reduced force nature becomes repulsive when the plates distance is not very tiny and finally the repulsive force vanishes with extremely large plates separation. The thermal influence causes the repulsive Casimir force greater. Within the frame of one-brane scenario the reduced Casimir force between the piston and one plate left keeps attractive no matter how high the temperature is. It is interesting that the thermal effect leads the attractive Casimir force greater instead of changing the force nature.

Hongbo Cheng

2011-12-29T23:59:59.000Z

329

Finite-size effects for the Ising model on helical tori N. Sh. Izmailian1,2,3  

E-Print Network (OSTI)

Finite-size effects for the Ising model on helical tori N. Sh. Izmailian1,2,3 and Chin-Kun Hu1 11 October 2007 We analyze the exact partition function of the Ising model on a square lattice under attention in recent decades. Based on the exactly known partition function of the two-dimensional 2D Ising

330

FINITE RATE OF INNOVATION BASED MODELING AND COMPRESSION OF ECG G. Baechler N. Freris R.F. Quick  

E-Print Network (OSTI)

FINITE RATE OF INNOVATION BASED MODELING AND COMPRESSION OF ECG SIGNALS G. Baechler N. Freris R and compress ECG signals. This technique generalizes classical FRI estimation to enable the use of a sum of asym- metric Cauchy-based pulses for modeling electrocardiogram (ECG) signals. We experimentally show

Dalang, Robert C.

331

Measurement and modeling of uranium and strategic element sorption by amidoxime resins in natural seawater  

E-Print Network (OSTI)

MEASUREMENT AND MODELING OF URANIUM AND STRATEGIC ELEMENT SORPTION BY AMIDOXIME RESINS IN NATURAL SEAMATER A Thesis by JOSE GREGORIO PINA-JORDAN Submitted to the Graduate College oi' Texas A&M University in partial I...'ulfillment of the requirements for the degree of MASTER OP SCIENCE December i985 Major Subject: Nuclear Engineering MEASUREMENT AND MODELING OF URANIUM AND STRATEGIC ELEMENT SORPTION BY AMIDOXIME RESINS IN NATURAL SEANATER A thesis by JOSE GREGORIO PINA...

Pina-Jordan, Jose Gregorio

2012-06-07T23:59:59.000Z

332

E-Print Network 3.0 - aponeurotic tension model Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

resolution. Once tension effects are explicitly modeled with forces at the liquid interface, many... finite element method to discretize our model for the surface tension...

333

Rare earth element sorption onto hydrous manganese oxide A modeling study  

E-Print Network (OSTI)

element sorption onto hydrous manganese oxide A modeling study Olivier Pourret1* and Mélanie Davranche2 1 models due to the lack of a comprehensive set of sorption reactions consistent with a given surface complexation model (SCM), as well as discrepancies between published sorption data and predictions using

Paris-Sud XI, Université de

334

Meson properties at finite temperature in a three flavor nonlocal chiral quark model with Polyakov loop  

SciTech Connect

We study the finite temperature behavior of light scalar and pseudoscalar meson properties in the context of a three-flavor nonlocal chiral quark model. The model includes mixing with active strangeness degrees of freedom, and takes care of the effect of gauge interactions by coupling the quarks with the Polyakov loop. We analyze the chiral restoration and deconfinement transitions, as well as the temperature dependence of meson masses, mixing angles and decay constants. The critical temperature is found to be T{sub c{approx_equal}}202 MeV, in better agreement with lattice results than the value recently obtained in the local SU(3) PNJL model. It is seen that above T{sub c} pseudoscalar meson masses get increased, becoming degenerate with the masses of their chiral partners. The temperatures at which this matching occurs depend on the strange quark composition of the corresponding mesons. The topological susceptibility shows a sharp decrease after the chiral transition, signalling the vanishing of the U(1){sub A} anomaly for large temperatures.

Contrera, G. A. [Physics Department, Comision Nacional de Energia Atomica, Av.Libertador 8250, (1429) Buenos Aires (Argentina); CONICET, Rivadavia 1917, 1033 Buenos Aires (Argentina); Dumm, D. Gomez [CONICET, Rivadavia 1917, 1033 Buenos Aires (Argentina); IFLP, Dpto. de Fisica, Universidad Nacional de La Plata, C.C. 67, (1900) La Plata (Argentina); Scoccola, Norberto N. [Physics Department, Comision Nacional de Energia Atomica, Av.Libertador 8250, (1429) Buenos Aires (Argentina); CONICET, Rivadavia 1917, 1033 Buenos Aires (Argentina); Universidad Favaloro, Solis 453, (1078) Buenos Aires (Argentina)

2010-03-01T23:59:59.000Z

335

Frequency domain and finite difference modeling of ventilated concrete slabs and comparison with field measurements: Part 1, modeling methodology  

Science Journals Connector (OSTI)

Abstract This paper is the first of two papers that focus on the thermal modeling of building-integrated thermal energy storage (BITES) systems using frequency response (FR) and lumped-parameter finite difference (LPFD) techniques. Structural/non-structural building fabric components, such as ventilated concrete slabs (VCS) can actively store and release thermal energy effectively by passing air through their embedded air channels. These building components can be described as ventilated BITES systems. To assist the thermal analysis and control of BITES systems, modeling techniques and guidelines for FR and LPFD models of VCS are presented in this two-part paper. In this first part, modeling techniques for FR and LPFD approaches based on network theory are presented. A method for calculating the heat transfer between flowing air and ventilated components is developed for these two approaches. Discretization criteria for explicit LPFD models are discussed. For the FR approach, discrete Fourier series in complex frequency form are used to represent the boundary excitations. In the treatment of heat injection from the flowing air as internal source in the VCS, network techniques such as Thévenin theorem, heat flow division, and Y-diakoptic transform are employed. The techniques presented in this paper are applicable to other BITES with hydronic or electric charging/discharging systems. With the FR techniques, model-based control strategies based on transfer functions can be readily developed.

Yuxiang Chen; Andreas K. Athienitis; Khaled E. Galal

2013-01-01T23:59:59.000Z

336

Accurate shell-model nuclear matrix elements for neutrinoless double-beta decay  

E-Print Network (OSTI)

We investigate a novel method of accurate calculation of the neutrinoless double-$\\beta$ decay shell-model nuclear matrix elements for the experimentally relevant case of $^{76}$Ge. We demonstrate that with the new method the nuclear matrix elements have perfect convergence properties and, using only the first 100 intermediate states of each spin, the matrix elements can be calculated with better than 1% accuracy. Based on the analysis of neutrinoless double-beta decays of $^{48}$Ca, $^{82}$Se, and $^{76}$Ge isotopes, we propose a new method to estimate the optimal values of the average closure energies at which the closure approximation gives the most accurate nuclear matrix elements. We also analyze the nuclear matrix elements for the heavy-neutrino-exchange mechanism, and we show that our method can be used to quench contributions from different intermediate spin states.

R. A. Sen'kov; M. Horoi

2014-11-06T23:59:59.000Z

337

Building ventilation : a pressure airflow model computer generation and elements of  

E-Print Network (OSTI)

Building ventilation : a pressure airflow model computer generation and elements of validation H - design #12;1- Introduction Regarding the number of airflow network models found in building publications Abstract : The calculation of airflows is of great importance for detailed building thermal simulation

Paris-Sud XI, Université de

338

Finite-size effects on the phase diagram of difermion condensates in two-dimensional four-fermion interaction models  

SciTech Connect

We investigate finite-size effects on the phase structure of chiral and difermion condensates at finite temperature and density in the framework of the two-dimensional large-N Nambu-Jona-Lasinio model. We take into account size-dependent effects by making use of zeta-function and compactification methods. The thermodynamic potential and the gap equations for the chiral and difermion condensed phases are then derived in the mean-field approximation. Size-dependent critical lines separating the different phases are obtained considering antiperiodic boundary conditions for the spatial coordinate.

Abreu, L. M.; Malbouisson, J. M. C. [Instituto de Fisica, Universidade Federal da Bahia, 40210-340, Salvador, BA (Brazil); Malbouisson, A. P. C. [Centro Brasileiro de Pesquisas Fisicas, MCT, 22290-180, Rio de Janeiro, RJ (Brazil)

2011-01-15T23:59:59.000Z

339

A graphical preprocessing interface for non-conforming spectral element solvers  

E-Print Network (OSTI)

Page 1 Left: Discretization of a square using 50?50 1 st order elements by FEM. Right: Discretizations of a square using 50 th -order single domain with SM... representative numerical technique of this kind is the Finite Element Method (FEM) [2]. It uses small finite number of elements with low order approximation functions (Fig. 1 left). When engineering models have complex geometry, FEM discretizes the geometry (e...

Kim, Bo Hung

2009-06-02T23:59:59.000Z

340

Modeling and numerical analysis of the bond behavior of masonry elements strengthened with SRP/SRG  

Science Journals Connector (OSTI)

Abstract Steel Reinforced Polymers (SRPs) and Steel Reinforced Grout (SRG) strengthening systems have been recently introduced as an alternative solution to the traditional systems based on the use of fiber reinforced polymers materials (FRPs). Few studies on SRP/SRG are available in the current literature and all have shown the potentialities of SRP/SRG in improving structural performances of masonry and concrete elements and, at the same time, their difference with respect to \\{FRPs\\} particularly in terms of bond behavior. Aim of the present paper is to propose a simple approach devoted to study the bond behavior of masonry structures strengthened with SRP/SRG systems. The approach, based on experimental evidences and theoretical considerations mainly consists of deriving approximate bond stress-slip laws for the strengthening/support interface layer, able to reproduce the local bond stresses transferring mechanism. Finite Element (FE) analyses are then developed with reference to the experimental tests available in the current literature by adopting the bond stress-slip laws obtained through the proposed approach. The deduced results show the reliability of the proposed approach in simulating the bond behavior of masonry elements strengthened with SRP/SRG and the possibility to investigate further peculiarities characterizing this kind of strengthening systems.

Ernesto Grande; Maura Imbimbo; Elio Sacco

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling finite element" 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

Numerical Modeling of Hydraulic Fracture Propagation Using Thermo-hydro-mechanical Analysis with Brittle Damage Model by Finite Element Method  

E-Print Network (OSTI)

Better understanding and control of crack growth direction during hydraulic fracturing are essential for enhancing productivity of geothermal and petroleum reservoirs. Structural analysis of fracture propagation and impact on fluid flow is a...

Min, Kyoung

2013-07-16T23:59:59.000Z

342

Modeling LiH potential-energy curves: An approach based on integration in finite space  

Science Journals Connector (OSTI)

In this paper, we introduce a finite-space integration method to shed physical insight into the interactions of a Rydberg electron with a molecular ion core, as sampled by the potential-energy curves (PECs) of various electronic states of LiH. We postulate that these interactions are dominated by two independent electron-atom processes: (1) scattering of the Rydberg electron at negative energy solely off of the lithium atomic core and (2) a transition from the lithium scattering state to the lithium valence orbital necessarily accompanied by an excitation of the hydrogen atom. It is shown that the ratio of the amplitudes for the occurrences of these two processes can be obtained by means of bounded integrations inside a small region of space where the electron-electron repulsion term in the Hamiltonian is dominant. Our theory and approximations are verified by a comparison of derived potential-energy curves with those produced by ab initio calculations as well as another empirical model that uses the Fermi approximation. It is observed that the complicated features of the PECs, which reflect the nodal structure of the Rydberg orbitals, are reproduced well within our treatment.

S. N. Altunata and R. W. Field

2003-02-28T23:59:59.000Z

343

Beyond-the-Standard-Model matrix elements with the gradient flow  

E-Print Network (OSTI)

At the Forschungszentrum Juelich (FZJ) we have started a long-term program that aims to determine beyond-the-Standard-Model (BSM) matrix elements using the gradient flow, and to understand the impact of BSM physics in nucleon and nuclear observables. Using the gradient flow, we propose to calculate the QCD component of key beyond the Standard Model (BSM) matrix elements related to quark and strong theta CP violation and the strange content within the nucleon. The former set of matrix elements impacts our understanding of Electric Dipole Moments (EDMs) of nucleons and nuclei (a key signature of BSM physics), while the latter contributes to elastic recoil of Dark Matter particles off nucleons and nuclei. If successful, these results will lay the foundation for extraction of BSM observables from future low-energy, high-intensity and high-accuracy experimental measurements.

A. Shindler; J. de Vries; T. Luu

2014-09-09T23:59:59.000Z

344

Beyond-the-Standard-Model matrix elements with the gradient flow  

E-Print Network (OSTI)

At the Forschungszentrum Juelich (FZJ) we have started a long-term program that aims to determine beyond-the-Standard-Model (BSM) matrix elements using the gradient flow, and to understand the impact of BSM physics in nucleon and nuclear observables. Using the gradient flow, we propose to calculate the QCD component of key beyond the Standard Model (BSM) matrix elements related to quark and strong theta CP violation and the strange content within the nucleon. The former set of matrix elements impacts our understanding of Electric Dipole Moments (EDMs) of nucleons and nuclei (a key signature of BSM physics), while the latter contributes to elastic recoil of Dark Matter particles off nucleons and nuclei. If successful, these results will lay the foundation for extraction of BSM observables from future low-energy, high-intensity and high-accuracy experimental measurements.

Shindler, A; Luu, T

2014-01-01T23:59:59.000Z

345

Determination of the effect of part orientation to the strength value on additive manufacturing FDM for end-use parts by physical testing and validation via three-dimensional finite element analysis  

Science Journals Connector (OSTI)

Determining the mechanical properties of the parts manufactured from additive manufacturing (AM) technology is important for manufacture end-use functional parts, known as rapid manufacturing (RM). It is important, within RM design, to verify to some degree of confidence that a part designed to be manufactured using this technology will be suitable and fit to function as intended, prior to committing to manufacture. The method of doing this is to perform physical testing on fabricated parts and validate via finite element analysis (FEA) on the parts.

R.H. Hambali; P. Smith; A.E.W. Rennie

2012-01-01T23:59:59.000Z

346

GOMA 6.0 : a full-Newton finite element program for free and moving boundary problems with coupled fluid/solid momentum, energy, mass, and chemical species transport : user%3CU%2B2019%3Es guide.  

SciTech Connect

Goma 6.0 is a finite element program which excels in analyses of multiphysical processes, particularly those involving the major branches of mechanics (viz. fluid/solid mechanics, energy transport and chemical species transport). Goma is based on a full-Newton-coupled algorithm which allows for simultaneous solution of the governing principles, making the code ideally suited for problems involving closely coupled bulk mechanics and interfacial phenomena. Example applications include, but are not limited to, coating and polymer processing flows, super-alloy processing, welding/soldering, electrochemical processes, and solid-network or solution film drying. This document serves as a user's guide and reference.

Schunk, Peter Randall; Rao, Rekha Ranjana; Chen, Ken Shuang; Labreche, Duane A.; Sun, Amy Cha-Tien; Hopkins, Matthew Morgan; Moffat, Harry K.; Roach, Robert Allen; Hopkins, Polly L.; Notz, Patrick K.; Roberts, Scott Alan; Sackinger, Philip A.; Subia, Samuel Ramirez; Wilkes, Edward Dean; Baer, Thomas A.; Noble, David R.; Secor, Robert B. [3M Engineering Systems and Technology, St. Paul, MN] [3M Engineering Systems and Technology, St. Paul, MN

2013-07-01T23:59:59.000Z

347

A few new (?) facts about infinite elements  

E-Print Network (OSTI)

Keywords: Helmholtz equation; Infinite element; hp finite elements; Echo Area. 1. .... ¼ g :¼ ? ouinc on . ?2.1?. The Sommerfeld radiation condition represents a ...

2006-04-24T23:59:59.000Z

348

Finite-temperature phase diagram of nonmagnetic impurities in high-temperature superconductors using a d=3 tJ model with quenched disorder  

E-Print Network (OSTI)

Finite-temperature phase diagram of nonmagnetic impurities in high-temperature superconductors a quenched disordered d=3 tJ Hamiltonian with static vacancies as a model of nonmagnetic impurities in high-Tc materials. Using a renormalization-group approach, we calculate the evolution of the finite-temperature

Thirumalai, Devarajan

349

Coupled Model for Heat and Water Transport in a High Level Waste...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

algorithm for mineral dehydration is also applied in the modeling. The Finite Element Heat and Mass transfer code (FEHM) is used to simulate coupled thermal, hydrological, and...

350

Discrete element modeling of rock deformation, fracture network development and permeability evolution under hydraulic stimulation  

SciTech Connect

Key challenges associated with the EGS reservoir development include the ability to reliably predict hydraulic fracturing and the deformation of natural fractures as well as estimating permeability evolution of the fracture network with time. We have developed a physics-based rock deformation and fracture propagation simulator by coupling a discrete element model (DEM) for fracturing with a network flow model. In DEM model, solid rock is represented by a network of discrete elements (often referred as particles) connected by various types of mechanical bonds such as springs, elastic beams or bonds that have more complex properties (such as stress-dependent elastic constants). Fracturing is represented explicitly as broken bonds (microcracks), which form and coalesce into macroscopic fractures when external and internal load is applied. The natural fractures are represented by a series of connected line segments. Mechanical bonds that intersect with such line segments are removed from the DEM model. A network flow model using conjugate lattice to the DEM network is developed and coupled with the DEM. The fluid pressure gradient exerts forces on individual elements of the DEM network, which therefore deforms the mechanical bonds and breaks them if the deformation reaches a prescribed threshold value. Such deformation/fracturing in turn changes the permeability of the flow network, which again changes the evolution of fluid pressure, intimately coupling the two processes. The intimate coupling between fracturing/deformation of fracture networks and fluid flow makes the meso-scale DEM- network flow simulations necessary in order to accurately evaluate the permeability evolution, as these methods have substantial advantages over conventional continuum mechanical models of elastic rock deformation. The challenges that must be overcome to simulate EGS reservoir stimulation, preliminary results, progress to date and near future research directions and opportunities will be discussed. Methodology for coupling the DEM model with continuum flow and heat transport models will also be discussed.

Shouchun Deng; Robert Podgorney; Hai Huang

2011-02-01T23:59:59.000Z

351

Nonlocal Polyakov-Nambu-Jona-Lasinio model with wave function renormalization at finite temperature and chemical potential  

SciTech Connect

We study the phase diagram of strongly interacting matter in the framework of a nonlocal SU(2) chiral quark model which includes wave function renormalization and coupling to the Polyakov loop. Both nonlocal interactions based on the frequently used exponential form factor, and on fits to the quark mass and renormalization functions obtained in lattice calculations are considered. Special attention is paid to the determination of the critical points, both in the chiral limit and at finite quark mass. In particular, we study the position of the critical end point as well as the value of the associated critical exponents for different model parametrizations.

Contrera, G. A. [Physics Department, Comision Nacional de Energia Atomica, Av.Libertador 8250, 1429 Buenos Aires (Argentina); CONICET, Rivadavia 1917, 1033 Buenos Aires (Argentina); Orsaria, M. [CONICET, Rivadavia 1917, 1033 Buenos Aires (Argentina); Gravitation, Astrophysics and Cosmology Group, FCAyG, UNLP, La Plata (Argentina); Scoccola, N. N. [Physics Department, Comision Nacional de Energia Atomica, Av.Libertador 8250, 1429 Buenos Aires (Argentina); CONICET, Rivadavia 1917, 1033 Buenos Aires (Argentina); Universidad Favaloro, Solis 453, 1078 Buenos Aires (Argentina)

2010-09-01T23:59:59.000Z

352

Statistical properties of the localization measure in a finite-dimensional model of the quantum kicked rotator  

E-Print Network (OSTI)

We study the quantum kicked rotator in the classically fully chaotic regime $K=10$ and for various values of the quantum parameter $k$ using Izrailev's $N$-dimensional model for various $N \\le 3000$, which in the limit $N \\rightarrow \\infty$ tends to the exact quantized kicked rotator. By numerically calculating the eigenfunctions in the basis of the angular momentum we find that the localization length ${\\cal L}$ for fixed parameter values has a certain distribution, in fact its inverse is Gaussian distributed, in analogy and in connection with the distribution of finite time Lyapunov exponents of Hamilton systems. However, unlike the case of the finite time Lyapunov exponents, this distribution is found to be independent of $N$, and thus survives the limit $N=\\infty$. This is different from the tight-binding model of Anderson localization. The reason is that the finite bandwidth approximation of the underlying Hamilton dynamical system in the Shepelyansky picture (D.L. Shepelyansky, {\\em Phys. Rev. Lett.} {\\bf 56}, 677 (1986)) does not apply rigorously. This observation explains the strong fluctuations in the scaling laws of the kicked rotator, such as e.g. the entropy localization measure as a function of the scaling parameter $\\Lambda={\\cal L}/N$, where $\\cal L$ is the theoretical value of the localization length in the semiclassical approximation. These results call for a more refined theory of the localization length in the quantum kicked rotator and in similar Floquet systems, where we must predict not only the mean value of the inverse of the localization length $\\cal L$ but also its (Gaussian) distribution, in particular the variance. In order to complete our studies we numerically analyze the related behavior of finite time Lyapunov exponents in the standard map and of the 2$\\times$2 transfer matrix formalism. This paper is extending our recent work.

T Manos; M Robnik

2015-01-21T23:59:59.000Z

353

Modeling and design optimization of switched reluctance machine by boundary element analysis and simulation  

SciTech Connect

Nonlinear boundary element analysis provides a more accurate and detailing tool for the design of switched reluctance machines, than the conventional equivalent-circuit methods. Design optimization through more detailed analysis and simulation can reduce development and prototyping costs and time to market. Firstly, magnetic field modeling of an industrial switched reluctance machine by boundary element method is reported in this paper. Secondly, performance prediction and dynamic simulation of motor and control design are presented. Thirdly, magnetic forces that cause noise and vibration are studied, to include the effects of motor and control design variations on noise in the design process. Testing of the motor in NEMA 215-Frame size is carried out to verify the accuracy of modeling and simulation.

Tang, Y.; Kline, J.A. Sr. [Emerson Motor Technology Center, St. Louis, MO (United States). U.S. Electrical Motors Div.] [Emerson Motor Technology Center, St. Louis, MO (United States). U.S. Electrical Motors Div.

1996-12-01T23:59:59.000Z

354

Journal of Biomechanics 34 (2001) 12791289 A nonlinear anisotropic model for porcine aortic heart valves  

E-Print Network (OSTI)

Journal of Biomechanics 34 (2001) 1279­1289 A nonlinear anisotropic model for porcine aortic heart finite element model for porcine heart valves. The model is based on the uniaxial experimental data of porcine aortic heart valve leaflet and the properties of nonlinear composite material. A finite element

Luo, Xiaoyu

355

Singlet oxygen generation according to flame-sheet and finite-rate chlorine/BHP reaction models. [Basic Hydrogen Peroxide  

SciTech Connect

In a flowing chemical oxygen--iodine laser, the photon energy is emitted by excited iodine atoms. These atoms are produced by energy transfer from O[sub 2]([sup 1][Delta]) after molecular iodine is dissociated upon mixing and reaction with the O[sub 2]([sup 1][Delta]). The generation of singlet delta oxygen, O[sub 2]([sup 1][Delta]), following gaseous chlorine diffusion into and reaction with liquid basic hydrogen peroxide (solution of KOH or NaOH in H[sub 2]O[sub 2] and H[sub 2]O) is investigated. Both flame-sheet and finite-rate reaction models for Cl[sub 2]/BHP are developed. A closed-form solution for the O[sub 2]([sup 1][Delta]) yield is obtained with the flame-sheet analysis, while a solution involving an integral equation is derived with the finite-rate analysis. The models are applied to a rotating disk type O[sub 2]([sup 1][Delta]) generator for illustration. The results do not differ greatly between the two models, and they show favorable agreement with reported experimental data.

Quan, V.; Copeland, D.A.; Blauer, J.A.; Rodriguez, S.E. (Rockwell International, Canoga Park, CA (United States). Rocketdyne Div.)

1994-05-01T23:59:59.000Z

356

Energy Landscape of the Finite-Size Mean-field 2-Spin Spherical Model and Topology Trivialization  

E-Print Network (OSTI)

Motivated by the recently observed phenomenon of topology trivialization of potential energy landscapes (PELs) for several statistical mechanics models, we perform a numerical study of the finite size $2$-spin spherical model using both numerical polynomial homotopy continuation and a reformulation via non-hermitian matrices. The continuation approach computes all of the complex stationary points of this model while the matrix approach computes the real stationary points. Using these methods, we compute the average number of stationary points while changing the topology of the PEL as well as the variance. Histograms of these stationary points are presented along with an analysis regarding the complex stationary points. This work connects topology trivialization to two different branches of mathematics: algebraic geometry and catastrophe theory, which is fertile ground for further interdisciplinary research.

Dhagash Mehta; Jonathan D. Hauenstein; Matthew Niemerg; Nicholas J. Simm; Daniel A. Stariolo

2014-09-29T23:59:59.000Z

357

Rare Earth Element sorption by basaltic rock: experimental data and modeling results using the "Generalised Composite approach".  

E-Print Network (OSTI)

Rare Earth Element sorption by basaltic rock: experimental data and modeling results using Email address : emmanuel.tertre@univ-poitiers.fr Keywords: sorption, lanthanides, basalt, surface.1016/j.gca.2007.12.015 #12;Abstract Sorption of the 14 Rare Earth Elements (REE) by basaltic rock

Paris-Sud XI, Université de

358

The 2004 Ultrasonic Benchmark Problem - SDH Response Under Oblique Incidence: Measurements and Patch Element Model Calculations  

SciTech Connect

The 2004 ultrasonic benchmark problem requires models to predict, given a reference pulse waveform, the pulse echo response of cylindrical voids of various radii located in an elastic solid for various incidence angles of a transducer immersed in water. We present the results of calculations based on the patch element model, recently developed at CNDE, to determine the response of an SDH in aluminum for specific oblique incidence angles. Patch element model calculations for a scan across the SDH, involving a range of oblique incidence angles, are also presented. Measured pulse-echo scans involving the SDH response under oblique incidence conditions are reported. In addition, through transmission measurements involving a pinducer as a receiver and an immersion planar probe as a transmitter under oblique incidence conditions are also reported in a defect-free Aluminum block. These pinducer-based measurements on a defect-free block are utilised to characterize the fields at the chosen depth. Comparisons are made between predictions and measurements for the pulse-echo response of a SDH.

Krishnamurthy, C. V.; Shankar, M.; Vardhan, J. Vishnu [Centre for NonDestructive Evaluation, Indian Institute of Technology, Chennai, India 600 036 (India); Balasubramaniam, Krishnan [Department of Mechanical Engineering, Indian Institute of Technology, Chennai, India 600 036 (India)

2006-03-06T23:59:59.000Z

359

Shell Model Two Body Matrix Elements Calculations for the Neutrinoless Double Beta Decay of 48 Ca  

Science Journals Connector (OSTI)

In this paper we present two Shell Model approaches for computing the two?body matrix elements involved in the neutrinoless double beta decay of 48 Ca. One of the methods involves integration of the radial part over the momentum space while the other only requires computations in the coordinate space. This has an influence in the complexity of the numerical approach and the necessary computation time. We will explain how this reflects into the obtained results pointing out the advantages and the limitations of each method.

2010-01-01T23:59:59.000Z

360

Modeling and simulation for a PEM fuel cell with catalyst layers in finite thickness.  

E-Print Network (OSTI)

??A detailed non-isothermal computational fluid dynamics (CFD) model for proton electrolyte membrane (PEM) fuel cells is developed in this thesis. This model consists of the… (more)

Yin, Jianghui (Author)

2007-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling finite element" 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

Frequency domain and finite difference modeling of ventilated concrete slabs and comparison with field measurements: Part 2. Application  

Science Journals Connector (OSTI)

Abstract This paper is the second of two papers that present techniques and guidelines for frequency response (FR) and lumped-parameter finite difference (LPFD) approaches for the thermal modeling of building-integrated thermal energy storage (BITES) systems. To assist the thermal analysis and control of active BITES systems, development of FR and LPFD models are presented in this two-part paper. Modeling methodology and techniques are presented in paper Part 1 using ventilated concrete slabs (VCS) for demonstration. In this part, the methodology is applied to two types of VCS. The modeling results from different FR and explicit LPFD models with different time steps and discretization schemes are presented. The results are compared to each other, and with field-measured data from a solar demonstration house with a VCS. Simulation results show that time step of half an hour for FR models results in less than 3% error in thermal performance. For LPFD models, discretization with Biot number smaller than 0.5 can reduce error to about 5%.

Yuxiang Chen; Andreas K. Athienitis; Khaled E. Galal

2013-01-01T23:59:59.000Z

362

Finite element modelling of marine controlled-source electromagnetic responses in two-dimensional dipping anisotropic conductivity structures  

Science Journals Connector (OSTI)

......200 and 500 omegam) in the anisotropic reservoir from Fig. 3. The...geometric mean resistivity of the anisotropic reservoir (asterisks), respectively. Impact of Dipping Anisotropic Overburden on an Underlying...sedimentary sequences including shales and thinly interbedded sandstones......

Yuguo Li; Shikun Dai

2011-05-01T23:59:59.000Z

363

Progressive Damage Analysis of Laminated Composite (PDALC)-A Computational Model Implemented in the NASA COMET Finite Element Code  

Science Journals Connector (OSTI)

A method for analysis of progressive failure in the Computational Structural Mechanics Testbed is presented in this report. The relationship employed in this analysis describes the matrix crack damage and fiber fracture via kinematics-based volume-averaged ...

Lo David C.; Coats Timothy W.; Harris Charles E.; Allen David H.

1996-11-01T23:59:59.000Z

364

Finite element modeling and experimental study of brittle fracture in tempered martensitic steels for thermonuclear fusion applications.  

E-Print Network (OSTI)

??In this work we have studied brittle fracture in high-chromium reduced activation tempered martensitic steels foreseen as structural materials for thermonuclear fusion reactors. Developing the… (more)

Mueller, Pablo Federico

2009-01-01T23:59:59.000Z

365

Three Dimensional Controlled-source Electromagnetic Edge-based Finite Element Modeling of Conductive and Permeable Heterogeneities  

E-Print Network (OSTI)

Presence of cultural refuse has long posed a serious challenge to meaningful geological interpretation of near surface controlled–source electromagnetic data (CSEM). Cultural refuse, such as buried pipes, underground storage tanks, unexploded...

Mukherjee, Souvik

2010-10-12T23:59:59.000Z

366

Algebraic multigrid preconditioning within parallel finite-element solvers for 3-D electromagnetic modelling problems in geophysics  

Science Journals Connector (OSTI)

......These methods have low requirements for storage capacity, which is, in addition, fixed...of two half-spaces, which represent seawater (sigma0-=-3.3 S-m1) and sediments...of two half-spaces, which represent seawater (sigma0-=-3.3 S-m1) and sediments......

Jelena Koldan; Vladimir Puzyrev; Josep de la Puente; Guillaume Houzeaux; José María Cela

2014-01-01T23:59:59.000Z

367

CAE (computer aided engineering) driven durability model verification for the automotive structure development  

Science Journals Connector (OSTI)

Test/analysis correlation, in the refinement of finite element models to accord with test results of the modeled structure is an emerging field in the today's automotive industries. The accuracy of finite element analysis predictions in the linear and ... Keywords: CAE (computer aided engineering), Durability, EMBS (elastic multi body simulation), VPG (virtual proving ground), Vehicle body design

Dong-Chan Lee; Chang-Soo Han

2009-04-01T23:59:59.000Z

368

Non-perturbative modelling of energetic particle effects on resistive wall mode: Anisotropy and finite orbit width  

SciTech Connect

A non-perturbative magnetohydrodynamic-kinetic hybrid formulation is developed and implemented into the MARS-K code [Liu et al., Phys. Plasmas 15, 112503 (2008)] that takes into account the anisotropy and asymmetry [Graves et al., Nature Commun. 3, 624 (2012)] of the equilibrium distribution of energetic particles (EPs) in particle pitch angle space, as well as first order finite orbit width (FOW) corrections for both passing and trapped EPs. Anisotropic models, which affect both the adiabatic and non-adiabatic drift kinetic energy contributions, are implemented for both neutral beam injection and ion cyclotron resonant heating induced EPs. The first order FOW correction does not contribute to the precessional drift resonance of trapped particles, but generally remains finite for the bounce and transit resonance contributions, as well as for the adiabatic contributions from asymmetrically distributed passing particles. Numerical results for a 9MA steady state ITER plasma suggest that (i) both the anisotropy and FOW effects can be important for the resistive wall mode stability in ITER plasmas; and (ii) the non-perturbative approach predicts less kinetic stabilization of the mode, than the perturbative approach, in the presence of anisotropy and FOW effects for the EPs. The latter may partially be related to the modification of the eigenfunction of the mode by the drift kinetic effects.

Liu, Yueqiang, E-mail: yueqiang.liu@ccfe.ac.uk; Chapman, I. T. [Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom)] [Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Graves, J. P. [Ecole Polytechnique Federale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas, Association EURATOM-Confederation Suisse, 1015 Lausanne (Switzerland)] [Ecole Polytechnique Federale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas, Association EURATOM-Confederation Suisse, 1015 Lausanne (Switzerland); Hao, G. Z. [Southwestern Institute of Physics, PO Box 432, Chengdu 610041 (China)] [Southwestern Institute of Physics, PO Box 432, Chengdu 610041 (China); Wang, Z. R.; Menard, J. E.; Okabayashi, M. [Princeton Plasma Physics Laboratory, Princeton University, PO Box 451, Princeton, New Jersey 08543-0451 (United States)] [Princeton Plasma Physics Laboratory, Princeton University, PO Box 451, Princeton, New Jersey 08543-0451 (United States); Strait, E. J.; Turnbull, A. [General Atomics, P.O. Box 85608, San Diego, California 92186-5608 (United States)] [General Atomics, P.O. Box 85608, San Diego, California 92186-5608 (United States)

2014-05-15T23:59:59.000Z

369

Discrete Element Modeling Results of Proppant Rearrangement in the Cooke Conductivity Cell  

SciTech Connect

The study of propped fracture conductivity began in earnest with the development of the Cooke cell which later became part of the initial API standard. Subsequent developments included a patented multicell design to conduct 4 tests in a press at the same time. Other modifications have been used by various investigators. Recent studies by the Stim-Lab proppant consortium have indicated that the flow field across a Cooke proppant conductivity testing cell may not be uniform as initially believed which resulted is significantly different conductivity results. Post test analysis of low temperature metal alloy injections at the termination of proppant testing prior to the release of the applied stress suggest that higher flow is to be expected along the sides and top of the proppant pack than compared to the middle of the pack. To evaluate these experimental findings, a physics-based two-dimensional (2-D) discrete element model (DEM) was developed and applied to simulate proppant rearrangement during stress loading in the Cooke conductivity cell and the resulting porosity field. Analysis of these simulations are critical to understanding the impact of modification to the testing cell as well as understanding key proppant conductivity issues such as how these effects are manifested in proppant concentration testing results. The 2-D DEM model was constructed to represent a realistic cross section of the Cooke cell with a distribution of four material properties, three that represented the Cooke cell (steel, sandstone,square rings), and one representing the proppant. In principle, Cooke cell materials can be approximated as assemblies of independent discrete elements (particles) of various sizes and material properties that interact via cohesive interactions, repulsive forces, and frictional forces. The macroscopic behavior can then be modeled as the collective behavior of many interacting discrete elements. This DEM model is particularly suitable for modeling proppant mechanical interactions subjected to an applied stress, where the experimental cell is represented as a cohesive body composed of a large number of discrete elements, and proppants can be modeled as the individual discrete particles with various sizes (following the proppant size distribution-density function used in the test) that exhibit no cohesive strength between the particles. Initial 2-D DEM modeling results suggest that proppant rearrangement and non-uniform stress distribution across the proppant pack results in significant non-uniform porosity distribution across the Cooke cell. Larger porosities develop along the edge of the proppant pack beneath the square ring seal and would result in a disproportionate higher flow field along these edges as compared to the middle of the proppant pack. These results suggest that reported conductivity values determined by the Cooke cell may be biased to overestimate the actual conductivity of the proppant at high stresses and that modifications to the standard Cooke cell will affect the magnitude of this bias.

Earl Mattson; Hai Huang; Michael Conway; Lisa O'Connell

2014-02-01T23:59:59.000Z

370

Use of element model to evaluate transmissibility reduction due to barriers  

SciTech Connect

Water breakthrough has been observed a year earlier than expected in the productive Oseberg Formation in the Veslefrikk Field. Production data revealed extensive water override, whereas the opposite situation was expected based on a homogeneous and coarse flow simulation model. A new model was developed to include geological heterogeneities using a simple upscaling method. The Oseberg Fm. consists of an upper homogeneous unit (zone 2) and a lower unit containing thin barriers of shale and calcite cemented sandstone (zone 1). The barrier content varies laterally. When barriers are distributed in a complex 3D pattern, they reduce the upscaled horizontal transmissibility more than what is obtained by multiplying the sand permeability by the net-to-gross ratio (N/G). However, the transmissibility reduction strongly depends on the spatial distribution of barriers and their geometry. Therefore, a fine scale element model was used to derive the average transmissibility reduction as a function of N/G for alternative geological descriptions of the barriers. A geo-statistical method called General Marked Point Process was used to generate the fine scale descriptions. This work has resulted in a simple upscaling routine for horizontal transmissibility, which represents an effective bridge between geological evaluation of uncertainties and fluid flow simulation. The method combines geo-statistical and deterministic modelling in an elegant manner, recognising that most often these methods complement one another.

Svanes, T.; South, D.; Dronen, O.M. [Statoil, Bergen (Norway)

1997-08-01T23:59:59.000Z

371

Cooper pairing and finite-size effects in a Nambu–Jona-Lasinio-type four-fermion model  

Science Journals Connector (OSTI)

Starting from a NJL-type model with N fermion species, fermion and difermion condensates and their associated phase structures are considered at nonzero chemical potential ? and zero temperature in spaces with nontrivial topology of the form S1?S1?S1 and R2?S1. Special attention is devoted to the generation of the superconducting phase. In particular, for the cases of antiperiodic and periodic boundary conditions we have found that the critical curve of the phase transitions between the chiral symmetry breaking and superconducting phases as well as the corresponding condensates and particle densities strongly oscillate versus ??1/L, where L is the length of the circumference S1. Moreover, it is shown that at some finite values of L the superconducting phase transition is shifted to smaller values both of ? and particle density in comparison with the case of L=?.

D. Ebert and K. G. Klimenko

2010-07-27T23:59:59.000Z

372

Domain decomposition for coupling finite and boundary element methods in EEG Emmanuel Olivi1, Maureen Clerc1 and Theodore Papadopoulo1  

E-Print Network (OSTI)

in the patient head. Yet, the skull anisotropy happens to be highly anisotropic, and must then be modeled.e. for the brain and the scalp). A domain decomposition (DD) framework allows to split the global system. This work presents such a coupling formulation of a 3-DD method solving iteratively a BEM for the brain

Boyer, Edmond

373

Modelling elements of Smart Grids – Enhancing the \\{OSeMOSYS\\} (Open Source Energy Modelling System) code  

Science Journals Connector (OSTI)

‘Smart Grids’ are expected to help facilitate a better integration of distributed storage and demand response options into power systems and markets. Quantifying the associated system benefits may provide valuable design and policy insights. Yet many existing energy system models are not able to depict various critical features associated with Smart Grids in a single comprehensive framework. These features may for example include grid stability issues in a system with several flexible demand types and storage options to help balance a high penetration of renewable energy. Flexible and accessible tools have the potential to fill this niche. This paper expands on the Open Source Energy Modelling System (OSeMOSYS). It describes how ‘blocks of functionality’ may be added to represent variability in electricity generation, a prioritisation of demand types, shifting demand, and storage options. The paper demonstrates the flexibility and ease-of-use of \\{OSeMOSYS\\} with regard to modifications of its code. It may therefore serve as a useful test-bed for new functionality in tools with wide-spread use and larger applications, such as MESSAGE, TIMES, MARKAL, or LEAP. As with the core code of OSeMOSYS, the functional blocks described in this paper are available in the public domain.

M. Welsch; M. Howells; M. Bazilian; J.F. DeCarolis; S. Hermann; H.H. Rogner

2012-01-01T23:59:59.000Z

374

TXLINE-2: a finite length model to simulate the dispersion of pollutants from roadways  

E-Print Network (OSTI)

Modelling Near Roadways Gradient Transport Approach B. Existing Dispersion Models HIWAY-2 CALINE-3 TXLINE C. Methods of Deteimining Source Strl ngth 12 O. Methods of Testing and Compar1ng Models ties s Balance Tea t Comparison to Data l4 E. Data... Dispersion From Roadways E. Link Capabilities F. Comparison of Dispets1 on Mocieis Using Existing Data 72 Comparison to the GM Data 72 Comparison to the Texas Data 75 Comparison to the SRI Data General Discussion 90 CHAPTER V TABLE OF CONTENTS...

Schroeder, James Henry

2012-06-07T23:59:59.000Z

375

Multi-objective optimization for bus body with strength and rollover safety constraints based on surrogate models  

Science Journals Connector (OSTI)

It is important to consider the performances of lightweight, stiffness, strength and rollover safety when designing a bus body. In this paper, the finite element (FE) analysis models including strength, stiffness and rollover crashworthiness of a bus ... Keywords: Bus body, Finite element analysis, Multi-objective optimization, Surrogate model

Ruiyi Su; Liangjin Gui; Zijie Fan

2011-09-01T23:59:59.000Z

376

Fitted finite volume positive difference scheme for a stationary model of air pollution  

Science Journals Connector (OSTI)

A new approach is proposed for the numerical solution of boundary value one-dimensional problem of advection-diffusion equation which arises, among others, in air pollution modeling. Since the problem is posed in...

Tatiana Chernogorova; Lubin Lubin Vulkov

2014-11-01T23:59:59.000Z

377

Smart finite state devices: A modeling framework for demand response technologies  

E-Print Network (OSTI)

We introduce and analyze Markov Decision Process (MDP) machines to model individual devices which are expected to participate in future demand-response markets on distribution grids. We differentiate devices into the ...

Turitsyn, Konstantin

378

Constitutive modeling of the finite deformation behavior of membranes possessing a triangulated networked microstructure  

E-Print Network (OSTI)

Many biological, natural and synthetic materials possess a networked or micro-truss-like microstructure. In this thesis work, a general microstructurally-informed continuum level constitutive model of the large stretch ...

Arslan, Melis

2005-01-01T23:59:59.000Z

379

Performance of a Stirling engine regenerator having finite mass  

SciTech Connect

The performance of a Stirling engine regenerator subjected to sinusoidal mass flow rate and pressure variation is analyzed. It is shown that cyclic variations in the temperature of the matrix due to its finite mass lead to an increase in the apparent regenerator effectiveness, but a decrease in engine power. Approximate closed-form expressions for both of these effects are deduced. The results of this analysis are compared with the predictions of a finite-element system model, and good agreement is found.

Jones, J.D.

1986-10-01T23:59:59.000Z

380

Spectral element formulation for dynamic analysis of a coupled piezoelectric wafer and beam system  

Science Journals Connector (OSTI)

A spectral element model is developed to represent the dynamic response of a coupled piezoelectric wafer and beam system (CPBS) in which either a single or collocated piezoelectric wafers are bonded to a base beam. The Mindlin-Herrmann rod theory and ... Keywords: A coupled piezoelectric wafer and beam system (CPBS), Collocated piezoelectric wafers, Electro-mechanical interaction, Finite element method, Lamb waves, Spectral element method

Hyun Woo Park; Eun Jin Kim; Ki Lyong Lim; Hoon Sohn

2010-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling finite element" 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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381

Quantum Mechanics associated with a Finite Group  

E-Print Network (OSTI)

I describe, in the simplified context of finite groups and their representations, a mathematical model for a physical system that contains both its quantum and classical aspects. The physically observable system is associated with the space containing elements fxf for f an element in the regular representation of a given finite group G. The Hermitian portion of fxf is the Wigner distribution of f whose convolution with a test function leads to a mathematical description of the quantum measurement process. Starting with the Jacobi group that is formed from the semidirect product of the Heisenberg group with its automorphism group SL(2,F{N}) for N an odd prime number I show that the classical phase space is the first order term in a series of subspaces of the Hermitian portion of fxf that are stable under SL(2,F{N}). I define a derivative that is analogous to a pseudodifferential operator to enable a treatment that parallels the continuum case. I give a new derivation of the Schrodinger-Weil representation of the Jacobi group. Keywords: quantum mechanics, finite group, metaplectic. PACS: 03.65.Fd; 02.10.De; 03.65.Ta.

Robert W. Johnson

2006-04-20T23:59:59.000Z

382

Mechanistic modeling of Zircaloy deformation and fracture in fuel element analysis  

SciTech Connect

A review is given of the comprehensive model developed in the 1960's at the Bettis Atomic Power Laboratory to explain the creep of Zircaloy during neutron irradiation and applied to fuel element analysis and design. The in-pile softening observed at low stresses was hypothesized to be due to a combination of the growth-directed Roberts-Cottrell yielding creep originally proposed for ..cap alpha..-uranium and the formation of point defect loops preferentially on certain planes in response to the applied stress, with the second process being of relatively greater importance. The in-pile hardening observed at high stresses (or strain-rates) was proposed to be due to the cutting by dislocations of radiation-produced obstacles. In this stress (strain-rate) region, in-pile behavior was proposed to be identical to post-irradiation behavior. At intermediate stresses (strain-rates) a mechanism of radiation-enhanced climb around obstacles was suggested as being rate controlling. As the stress is decreased, the climb process becomes easier and the rate was then predicted to be controlled by glide at a flow stress characteristic of unirradiated, annealed material, where radiation-enhanced diffusion enabled climbing around the normal strain-hardening obstacles. At still lower stresses, this glide process became negligibly slow compared with the growth-connected creep mechanism which was presumed to operate independently. The overall scheme was shown to be good agreement with all the in-pile data then available and implemented into the computer analysis of fuel element behavior. 48 refs., 1 fig.

Nichols, F.A.

1985-06-01T23:59:59.000Z

383

Smart Finite State Devices: A Modeling Framework for Demand Response Technologies  

E-Print Network (OSTI)

We introduce and analyze Markov Decision Process (MDP) machines to model individual devices which are expected to participate in future demand-response markets on distribution grids. We differentiate devices into the following four types: (a) optional loads that can be shed, e.g. light dimming; (b) deferrable loads that can be delayed, e.g. dishwashers; (c) controllable loads with inertia, e.g. thermostatically-controlled loads, whose task is to maintain an auxiliary characteristic (temperature) within pre-defined margins; and (d) storage devices that can alternate between charging and generating. Our analysis of the devices seeks to find their optimal price-taking control strategy under a given stochastic model of the distribution market.

Turitsyn, Konstantin; Ananyev, Maxim; Chertkov, Michael

2011-01-01T23:59:59.000Z

384

DISCRETE ELEMENT MODELING OF BLADE–STRIKE FREQUENCY AND SURVIVAL OF FISH PASSING THROUGH HYDROKINETIC TURBINES  

SciTech Connect

Evaluating the consequences from blade-strike of fish on marine hydrokinetic (MHK) turbine blades is essential for incorporating environmental objectives into the integral optimization of machine performance. For instance, experience with conventional hydroelectric turbines has shown that innovative shaping of the blade and other machine components can lead to improved designs that generate more power without increased impacts to fish and other aquatic life. In this work, we used unsteady computational fluid dynamics (CFD) simulations of turbine flow and discrete element modeling (DEM) of particle motion to estimate the frequency and severity of collisions between a horizontal axis MHK tidal energy device and drifting aquatic organisms or debris. Two metrics are determined with the method: the strike frequency and survival rate estimate. To illustrate the procedure step-by-step, an exemplary case of a simple runner model was run and compared against a probabilistic model widely used for strike frequency evaluation. The results for the exemplary case showed a strong correlation between the two approaches. In the application case of the MHK turbine flow, turbulent flow was modeled using detached eddy simulation (DES) in conjunction with a full moving rotor at full scale. The CFD simulated power and thrust were satisfactorily comparable to experimental results conducted in a water tunnel on a reduced scaled (1:8.7) version of the turbine design. A cloud of DEM particles was injected into the domain to simulate fish or debris that were entrained into the turbine flow. The strike frequency was the ratio of the count of colliding particles to the crossing sample size. The fish length and approaching velocity were test conditions in the simulations of the MHK turbine. Comparisons showed that DEM-based frequencies tend to be greater than previous results from Lagrangian particles and probabilistic models, mostly because the DEM scheme accounts for both the geometric aspects of the passage event ---which the probabilistic method does--- as well as the fluid-particle interactions ---which the Lagrangian particle method does. The DEM-based survival rates were comparable to laboratory results for small fish but not for mid-size fish because of the considerably different turbine diameters. The modeling framework can be used for applications that aim at evaluating the biological performance of MHK turbine units during the design phase and to provide information to regulatory agencies needed for the environmental permitting process.

Romero Gomez, Pedro DJ; Richmond, Marshall C.

2014-04-17T23:59:59.000Z

385

Correlation energy of finite two-dimensional systems: Toward nonempirical and universal modeling  

Science Journals Connector (OSTI)

The capability of density-functional theory to deal with the ground state of strongly correlated low-dimensional systems, such as semiconductor quantum dots, depends on the accuracy of functionals developed for the exchange and correlation energies. Here we extend a successful approximation for the correlation energy of the three-dimensional inhomogeneous electron gas, originally introduced by Becke [J. Chem. Phys. 88, 1053 (1988)], to the two-dimensional case. The approach is based on nonempirical modeling of the correlation-hole functions satisfying a set of exact properties. Furthermore, the electron current and spin are explicitly taken into account. As a result, good performance is obtained in comparison with numerically exact data for quantum dots with varying external magnetic field, and for the homogeneous two-dimensional electron gas, respectively.

S. Pittalis; E. Räsänen; C. R. Proetto; E. K. U. Gross

2009-02-24T23:59:59.000Z

386

Pion condensation in the two--flavor chiral quark model at finite baryochemical potential  

E-Print Network (OSTI)

Pion condensation is studied at one--loop level and nonzero baryochemical potential in the framework of two flavor constituent quark model using the one--loop level optimized perturbation theory for the resummation of the perturbative series. A Landau type of analysis is presented for the investigation of the phase boundary between the pion condensed/non-condensed phases. The statement that the condensation starts at $\\muI = m_{\\pi}$ is slightly modified by one--loop corrections. The second order critical surface is determined and analysed in the $\\muI-\\muB-T$ space. The $\\muI$ dependence of the one--loop level charged pion pole masses is also studied.

T. Herpay; P. Kovács

2008-11-17T23:59:59.000Z

387

Neutron scattering from elemental indium, the optical model, and the bound-state potential  

SciTech Connect

Neutron differential elastic-scattering cross sections of elemental indium are measured from 4.5 to 10 MeV at incident-energy intervals of {approx}500 keV. Seventy or more differential values are obtained at each incident energy, distributed between {approx}18{degree} and 160{degree}. These experimental results are combined with lower-energy values previously obtained at this laboratory, and with 11 and 14 MeV results in the literature, to form a comprehensive elastic-scattering database extending from {approx}1.5 to 14 MeV. These data are interpreted in terms of a conventional spherical optical model. The resulting potential is extrapolated to the bound-state regime. It is shown that in the middle of the 50--82 neutron shell, the potential derived from the scattering results adequately describes the binding energies of article states, but does not do well for hole states. The latter shortcoming is attributed to the holes states having occupational probabilities sufficiently different from unity, so that the exclusion principle become a factor, and to the rearrangement of the neutron core. 68 refs.

Chiba, S. (Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan)); Guenther, P.T.; Lawson, R.D.; Smith, A.B. (Argonne National Lab., IL (USA))

1990-06-01T23:59:59.000Z

388

Programing the Finite Element Method with Matlab  

E-Print Network (OSTI)

Oct 3, 2002 ... font d denotes a vector or matrix which is of dimension of the ... following Matlab code which sets the row and column of a matrix A to zero.

2002-10-03T23:59:59.000Z

389

Finite Element Approximation of Coupled Seismic and ...  

E-Print Network (OSTI)

negative sign) is balanced by adsorbed positive ions of the surrounding fluid, setting ... Further from the surface there exists a distribution of mobile counter ions, ...

2009-02-15T23:59:59.000Z

390

Finite element analysis of shells with layers  

E-Print Network (OSTI)

It is well established that thin shell structures frequently feature narrow bands of strain concentration and localized displacement irregularities referred to as boundary and internal layers. It is crucial to capture these ...

Hiller, Jean-François, 1974-

2002-01-01T23:59:59.000Z

391

Generalized finite element method for multiscale analysis  

E-Print Network (OSTI)

by the Partition of Unity Method (PUM). It is shown that the p-version of the Generalized FEM using mesh-based handbook functions is capable of achieving very high accuracy. It is also analyzed that the effect of the main factors affecting the accuracy...

Zhang, Lin

2004-11-15T23:59:59.000Z

392

AN ADAPTIVE FINITE ELEMENT METHOD FOR THE ...  

E-Print Network (OSTI)

(R2) with Im ? ? 0 and Re ? > 0 whenever Im ? = 0. First, the problem .... tively refining mesh compared with by uniformly refining mesh. Thus, the present.

2014-05-20T23:59:59.000Z

393

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

394

Finite element approximation of coupled seismic and ...  

E-Print Network (OSTI)

Facultad de Ciencias Astronómicas y Geof? sicas, Universidad Nacional de La Plata and Department of Mathematics, Purdue University. Joint work with Fabio I.

395

PARTIALLY PENALIZED IMMERSED FINITE ELEMENT METHODS ...  

E-Print Network (OSTI)

v+(x, y) = c+. 1 + c+. 2 x + c+. 3 y, if (x, y) ? K+, which satisfies the following jump conditions [38]: v?(D) = v+(D), v?(E) = v+(E), ??. ?v?. ?nDE. = ?+ ?v+. ?nDE.

2014-03-14T23:59:59.000Z

396

Construction of Higher Order Finite Element with  

E-Print Network (OSTI)

accuracy, stability Previous work: ffl Cohen, Joly, Tordjman (2D, construction, analysis, performance) ffl \\Gamma4 [b] with b = â?? 1 â?? 2 â?? 3 â?? 4 (bubble function), and b f a iface bubblej function. Accuracy

Kern, Michel

397

Control-volume mixed finite element methods  

E-Print Network (OSTI)

Z. Cai a, J.E. Jones b, S.F. McCormick c and T.F. Russell d a Center for ...... (59). The Darcy equations for “vertical” faces normal to x-fluxes and y-fluxes would be.

1998-01-23T23:59:59.000Z

398

Modeling a thermionic energy converter using finite-difference time-domain particle-in-cell simulations  

SciTech Connect

A thermionic energy converter (TEC) is a static device that converts heat directly into electricity by boiling electrons off a hot emitter surface across a small inter-electrode gap to a cooler collector surface. The main challenge in TECs is overcoming the space charge limit, which limits the current transmitted across a gap of a given voltage and width. We have verified the feasibility of studying and developing a TEC using a bounded finite-difference time-domain particle-in-cell plasma simulation code, OOPD1, developed by Plasma Theory and Simulation Group, formerly at UC Berkeley and now at Michigan State University. In this preliminary work, a TEC has been modeled kinetically using OOPD1, and the accuracy has been verified by comparing with an analytically solvable case, giving good agreement. With further improvement of the code, one will be able to quickly and cheaply analyze space charge effects, and seek designs that mitigate the space charge effect, allowing TECs to become more efficient and cost-effective.

Lo, F. S.; Lee, T. H. [Department of Mechanical Engineering, National Central University, Jhongli City, Taoyuan County 32001, Taiwan (China)] [Department of Mechanical Engineering, National Central University, Jhongli City, Taoyuan County 32001, Taiwan (China); Lu, P. S. [NanoScience Simulation Laboratory, Fu Jen Catholic University, Xinzhuang Dist., New Taipei City 24205, Taiwan (China)] [NanoScience Simulation Laboratory, Fu Jen Catholic University, Xinzhuang Dist., New Taipei City 24205, Taiwan (China); Ragan-Kelley, B. [Applied Science and Technology, University of California, Berkeley, California 94720 (United States) [Applied Science and Technology, University of California, Berkeley, California 94720 (United States); Plasma Theory and Simulation Group, University of California, Berkeley, California 94720 (United States); Minnich, A. [Plasma Theory and Simulation Group, University of California, Berkeley, California 94720 (United States) [Plasma Theory and Simulation Group, University of California, Berkeley, California 94720 (United States); Division of Engineering and Applied Science, California Institute of Technology, Pasadena, California 91125 (United States); Lin, M. C., E-mail: mingchiehlin@gmail.com [NanoScience Simulation Laboratory, Fu Jen Catholic University, Xinzhuang Dist., New Taipei City 24205, Taiwan (China); Plasma Theory and Simulation Group, University of California, Berkeley, California 94720 (United States); Verboncoeur, J. P. [Plasma Theory and Simulation Group, University of California, Berkeley, California 94720 (United States) [Plasma Theory and Simulation Group, University of California, Berkeley, California 94720 (United States); Department of Electrical and Computing Engineering, Michigan State University, East Lansing, Michigan 48824 (United States)

2014-02-15T23:59:59.000Z

399

Nuclear matrix elements for 0??{sup ?}?{sup ?} decays: Comparative analysis of the QRPA, shell model and IBM predictions  

SciTech Connect

In this work we report on general properties of the nuclear matrix elements involved in the neutrinoless double ?{sup ?} decays (0??{sup ?}?{sup ?} decays) of several nuclei. A summary of the values of the NMEs calculated along the years by the Jyväskylä-La Plata collaboration is presented. These NMEs, calculated in the framework of the quasiparticle random phase approximation (QRPA), are compared with those of the other available calculations, like the Shell Model (ISM) and the interacting boson model (IBA-2)

Civitarese, Osvaldo [Department of Physics, University of La Plata, c.c. 67 1900, La Plata Argentina (Argentina); Suhonen, Jouni [Department of Physics, University of Jyväskylä, PO Box 35, FIN-40014 (Finland)

2013-12-30T23:59:59.000Z

400

linear-elements-code.scm  

E-Print Network (OSTI)

(o Linear-finite-element-operator)) ;; initialize various fields that depend on the space ;; if coefficients is not defined, we set it to arrays of floating-point ;; zeros ...

Note: This page contains sample records for the topic "modeling finite element" 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

Finite-size effects in kinetic phase transitions of a model reaction on a fractal surface: Scaling approach and Monte Carlo investigation  

Science Journals Connector (OSTI)

Finite-size effects in kinetic (irreversible) phase transitions, from reactive to poisoned states, occurring in model reactions are interpreted with the aid of a phenomenological scaling approach. The proposed arguments are tested by computer simulations of a model for the oxidation of carbon monoxide on a fractal surface. The critical exponents of the transitions displayed by the model and the exponents for the transient period of the reaction at criticality are evaluated. A crossover from a reactive steady state to a regime where the surface could be poisoned by each of the reactants is found and discussed.

Ezequiel V. Albano

1990-12-01T23:59:59.000Z

402

Uncertainties in nuclear transition matrix elements for neutrinoless ?? decay within the projected-Hartree-Fock-Bogoliubov model  

Science Journals Connector (OSTI)

The nuclear transition matrix elements M(0?) for the neutrinoless ?? decay of Zr94,96, Mo98,100, Ru104, Pd110, Te128,130, and Nd150 isotopes in the case of 0+?0+ transition are calculated using the projected-Hartree-Fock-Bogoliubov wave functions, which are eigenvectors of four different parametrizations of a Hamiltonian with pairing plus multipolar effective two-body interaction. Employing two (three) different parametrizations of Jastrow-type short-range correlations, a set of eight (twelve) different nuclear transition matrix elements M(0?) is built for each decay, whose averages in conjunction with their standard deviations provide an estimate of the model’s uncertainties.

P. K. Rath, R. Chandra, K. Chaturvedi, P. K. Raina, and J. G. Hirsch

2010-12-17T23:59:59.000Z

403

The Effects of Fluid Flow On Shear Localization and Frictional Strength From Dynamic Models Of Fault Gouge During Earthquakes  

E-Print Network (OSTI)

This thesis explores the effects of fluid flow on shear localization and frictional strength of fault gouge through the use of a coupled 2-phase (pore fluid-grain) Finite Difference-Discrete Element Numerical model. The model simulates slip...

Bianco, Ronald

2013-12-02T23:59:59.000Z

404

Introduction Positive finite rank . . .  

E-Print Network (OSTI)

Introduction Positive finite rank . . . Positive finite rank . . . Positive finite rank . . . ¯� I qixf1981@sxu.edu.cn #12;Introduction Positive finite rank . . . Positive finite rank . . . Positive finite rank . . . ¯� I K 12 19 £ ¶w« ' 4 ò � 1 Introduction · In quantum mechanics, a quantum system

Li, Chi-Kwong

405

Studies of an off-lattice model for protein folding: Sequence dependence and improved sampling at finite temperature  

E-Print Network (OSTI)

at finite temperature Anders Irba¨cka) and Frank Potthastb) Department of Theoretical Physics, University. We find that by these algorithms one gains large factors in efficiency in comparison to a fairly well-defined shape. This phase is interesting from the viewpoint of proteins, but for a generic

Irbäck, Anders

406

Painting-to-3D Model Alignment Via Discriminative Visual Elements  

E-Print Network (OSTI)

] as well as simplified models obtained from 3D mod- eling tools such as Google Sketchup. Example results

Paris-Sud XI, Université de

407

A LATTICE BOLTZMANN MODEL FOR CONVECTION HEAT TRANSFER IN POROUS MEDIA  

E-Print Network (OSTI)

A LATTICE BOLTZMANN MODEL FOR CONVECTION HEAT TRANSFER IN POROUS MEDIA Zhaoli Guo and T. S. Zhao Kong, China A lattice Boltzmann model for convection heat transfer in porous media is proposed-difference, finite-volume, and finite-element methods (e.g., [2, 3]). The lattice Boltzmann method (LBM

Zhao, Tianshou

408

Dynamic soil-structure interaction-comparison of FEM model with experimental results  

E-Print Network (OSTI)

to represent twenty different laboratory experiments. The results of these models are compared with results available from extensive experimental dynamic testing on a geotechnical centrifuge. Though the various results from the finite element analysis...

Srinivasan, Palanivel Rajan

2012-06-07T23:59:59.000Z

409

A numerical model for ultimate soil resistance to an untrenched pipeline under ocean currents  

Science Journals Connector (OSTI)

One of the main concerns for pipeline on-bottom stability design is to properly predict ultimate soil resistance in severe ocean environments. A plane-strain finite element model ... the partially-embedded pipeli...

Fu-ping Gao ???; Xi-ting Han ???; Shu-ming Yan ???

2012-06-01T23:59:59.000Z

410

A Continuum Coupled Moisture-mechanical Constitutive Model for Asphalt Concrete  

E-Print Network (OSTI)

constitutive relationships are implemented in the Pavement Analysis using Nonlinear Damage Approach (PANDA) finite element (FE) package to model the moisture damage effect on the complex environmental-mechanical response of asphalt concrete. The developed...

Shakiba, Maryam

2013-12-09T23:59:59.000Z

411

Development and numerical implementation of nonlinear viscoelastic-viscoplastic model for asphalt materials  

E-Print Network (OSTI)

pavements is illustrated using finite element simulations. The constitutive model developed in this study can describe the behavior of asphalt materials (asphalt binder, asphalt mastic and mixtures) under various testing conditions. This study also achieved...

Huang, Chien-Wei

2009-05-15T23:59:59.000Z

412

Microstructure-Based Computational Modeling of TRIP Steels with Dispersed Particles  

E-Print Network (OSTI)

in this study. The ideas surrounding the behavior of transformation induced plasticity (TRIP) steels and particle reinforced composites are combined and investigated. A finite element model (FEM) is created to investigate the effects of dispersed ceramic...

Diaz, Sara Cristina

2012-10-19T23:59:59.000Z

413

Bronchopulmonary Dysplasia, Idiopathic Pulmonary Arterial Hypertension, and Wave Modeling in Stented Vessels  

E-Print Network (OSTI)

arterial hypertension (PAH), to identify the hemodynamic attributes which could be altered to ameliorate the progression of these diseases. We then simulated blood flow through five, simple finite element vessel models to determine the effects of stents...

Peters, Andrew

2011-08-04T23:59:59.000Z

414

Comparison of different capillary bridge models for application in the discrete element method  

E-Print Network (OSTI)

Weakly wetted granular material is the subject of many studies. Several formulations were proposed to calculate the capillary forces between wet particles. In this paper some of such models have been implemented in a DEM-framework, and simulation results were compared to experimental measurements. Also, the influence of capillary model type on macro parameters like local shear viscosity and cohesive parameters of sheared material have been investigated through the simulation of spherical beads using a DEM-model of a split-bottom shear-cell. It was concluded that the water content, simulated with the help of capillary bridge models, changes the macro-properties of the simulated granular material. Different capillary bridge models do not influence the macroscopic results visibly.

Anton Gladkyy; Ruediger Schwarze

2014-03-31T23:59:59.000Z

415

Discrete Element Model for Simulations of Early-Life Thermal Fracturing Behaviors in Ceramic Nuclear Fuel Pellets  

SciTech Connect

A discrete element Model (DEM) representation of coupled solid mechanics/fracturing and heat conduction processes has been developed and applied to explicitly simulate the random initiations and subsequent propagations of interacting thermal cracks in a ceramic nuclear fuel pellet during initial rise to power and during power cycles. The DEM model clearly predicts realistic early-life crack patterns including both radial cracks and circumferential cracks. Simulation results clearly demonstrate the formation of radial cracks during the initial power rise, and formation of circumferential cracks as the power is ramped down. In these simulations, additional early-life power cycles do not lead to the formation of new thermal cracks. They do, however clearly indicate changes in the apertures of thermal cracks during later power cycles due to thermal expansion and shrinkage. The number of radial cracks increases with increasing power, which is consistent with the experimental observations.

Hai Huang; Ben Spencer; Jason Hales

2014-10-01T23:59:59.000Z

416

Numerical modeling of hydraulic fracture problem in permeable medium using cohesive zone model  

E-Print Network (OSTI)

Numerical modeling of hydraulic fracture problem in permeable medium using cohesive zone model-off dominated. We demonstrate the ability of our cohesive zone model in simulating the hydraulic fracture in all these propagation regimes. Keywords: Hydraulic fracture, Cohesive zone model, Finite element analysis, Hydro

Paris-Sud XI, Université de

417

Iterated finite-orbit Monte Carlo simulations with full-wave fields for modeling tokamak ion cyclotron resonance frequency wave heating experiments  

SciTech Connect

The five-dimensional finite-orbit Monte Carlo code ORBIT-RF[M. Choi et al., Phys. Plasmas 12, 1 (2005)] is successfully coupled with the two-dimensional full-wave code all-orders spectral algorithm (AORSA) [E. F. Jaeger et al., Phys. Plasmas 13, 056101 (2006)] in a self-consistent way to achieve improved predictive modeling for ion cyclotron resonance frequency (ICRF) wave heating experiments in present fusion devices and future ITER [R. Aymar et al., Nucl. Fusion 41, 1301 (2001)]. The ORBIT-RF/AORSA simulations reproduce fast-ion spectra and spatial profiles qualitatively consistent with fast ion D-alpha [W. W. Heidbrink et al., Plasma Phys. Controlled Fusion 49, 1457 (2007)] spectroscopic data in both DIII-D [J. L. Luxon, Nucl. Fusion 42, 614 (2002)] and National Spherical Torus Experiment [M. Ono et al., Nucl. Fusion 41, 1435 (2001)] high harmonic ICRF heating experiments. This work verifies that both finite-orbit width effect of fast-ion due to its drift motion along the torus and iterations between fast-ion distribution and wave fields are important in modeling ICRF heating experiments.

Choi, M.; Chan, V. S.; Lao, L. L.; Pinsker, R. I. [General Atomics, P.O. Box 85608, San Diego, California 92186-5608 (United States); Green, D.; Berry, L. A.; Jaeger, F.; Park, J. M. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830 (United States); Heidbrink, W. W.; Liu, D.; Podesta, M. [University of California-Irvine, Irvine, California 92697 (United States); Harvey, R. [CompX, P.O. Box 2672, Del Mar, California 92014-5672 (United States); Smithe, D. N. [Tech-X Corporation, Boulder, Colorado 80303 (United States); Bonoli, P. [Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

2010-05-15T23:59:59.000Z

418

Identifying protein-coding genes and synonymous constraint elements using phylogenetic codon models  

E-Print Network (OSTI)

We develop novel methods for comparative genomics analysis of protein-coding genes using phylogenetic codon models, in pursuit of two main lines of biological investigation: First, we develop PhyloCSF, an algorithm based ...

Lin, Michael F. (Michael Fong-Jay)

2012-01-01T23:59:59.000Z

419

Equivalence of finite difference approximation and digital waveguide modeling for lossless, nondispersive media in one to three dimensions  

Science Journals Connector (OSTI)

The finite difference approximation method is commonly used to convert a differential equation into a recursive computation for computer simulation of an acoustic medium. Less well known is the digital waveguidemodeling approach to the same problem which is based on simulating the propagation of sampled traveling waves in the medium and which implements losses and dispersion using digital filters applied to the traveling waves [Comput. Music. J. 74–91 (Winter 1992)]. It turns out the two methods are equivalent in rectilinear coordinates in one two and three dimensions in the lossless nondispersive case provided the spatial sampling interval is chosen to be a specific constant (c in the one?dimensional case) times the temporal sampling interval. Since the digital waveguide simulation technique requires far less computational effort it can be used to both accelerate and increase the accuracy of numerical simulations of acoustic media.

Julius O. Smith III; Scott A. Van Duyne

1995-01-01T23:59:59.000Z

420

Discrete–element modelling: methods and applications in the environmental sciences  

Science Journals Connector (OSTI)

...tectonic information from the inversion of seismic signals (Hazzard et al. 2002). A productive...the flocking or schooling of birds and fish are well-known examples. Models of this...of an entire flock of birds or school of fish. Here the results may depend on the existence...

2004-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling finite element" 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

Fast history matching of finite-difference model, compressible and three-phase flow using streamline-derived sensitivities  

E-Print Network (OSTI)

upscaled from fine-scale geologic/geocellular models to This dissertation follows the style and format of the SPE Journal. 2 coarser reservoir simulation models for field development studies...

Cheng, Hao

2006-10-30T23:59:59.000Z

422

One and two-dimensional finite difference models of pore pressure evolution within and below a moving thrust sheet  

E-Print Network (OSTI)

-dimensionalized numerical and analytical solutions of the one-dimensional model using identical parameters to solve Equation 3 when KH is homogeneous. . . . . . . . . . . , , , . . . . . . . . . . . , . . . . . . . . . . . , . , 36 12 Total pore pressure at the end... deposition) for the one-dimensional model. . 40 14 Total pore pressure at the end of Stage 3 (thrust loading) for the one- dimensional model. . 42 15 Decay of X with time beginning at the end of Stage 3 (thrust loading) for the one-dimensional model...

Smith, Richard Edwin

1992-01-01T23:59:59.000Z

423

Summary compilation of shell element performance versus formulation.  

SciTech Connect

This document compares the finite element shell formulations in the Sierra Solid Mechanics code. These are finite elements either currently in the Sierra simulation codes Presto and Adagio, or expected to be added to them in time. The list of elements are divided into traditional two-dimensional, plane stress shell finite elements, and three-dimensional solid finite elements that contain either modifications or additional terms designed to represent the bending stiffness expected to be found in shell formulations. These particular finite elements are formulated for finite deformation and inelastic material response, and, as such, are not based on some of the elegant formulations that can be found in an elastic, infinitesimal finite element setting. Each shell element is subjected to a series of 12 verification and validation test problems. The underlying purpose of the tests here is to identify the quality of both the spatially discrete finite element gradient operator and the spatially discrete finite element divergence operator. If the derivation of the finite element is proper, the discrete divergence operator is the transpose of the discrete gradient operator. An overall summary is provided from which one can rank, at least in an average sense, how well the individual formulations can be expected to perform in applications encountered year in and year out. A letter grade has been assigned albeit sometimes subjectively for each shell element and each test problem result. The number of A's, B's, C's, et cetera assigned have been totaled, and a grade point average (GPA) has been computed, based on a 4.0-system. These grades, combined with a comparison between the test problems and the application problem, can be used to guide an analyst to select the element with the best shell formulation.

Heinstein, Martin Wilhelm; Hales, Jason Dean (Idaho National Laboratory, Idaho Falls, ID); Breivik, Nicole L.; Key, Samuel W. (FMA Development, LLC, Great Falls, MT)

2011-07-01T23:59:59.000Z

424

Applications of Lagrangian Dispersion Modeling to the Analysis of Changes in the Specific Absorption of Elemental Carbon  

SciTech Connect

We use a Lagrangian dispersion model driven by a mesoscale model with four-dimensional data assimilation to simulate the dispersion of elemental carbon (EC) over a region encompassing Mexico City and its surroundings, the study domain for the 2006 MAX-MEX experiment, which was a component of the MILAGRO campaign. The results are used to identify periods when biomass burning was likely to have had a significant impact on the concentrations of elemental carbon at two sites, T1 and T2, downwind of the city, and when emissions from the Mexico City Metropolitan Area (MCMA) were likely to have been more important. They are also used to estimate the median ages of EC affecting the specific absorption of light, aABS, at 870 nm as well as to identify periods when the urban plume from the MCMA was likely to have been advected over T1 and T2. Values of aABS at T1, the nearer of the two sites to Mexico City, were smaller at night and increased rapidly after mid-morning, peaking in the mid-afternoon. The behavior is attributed to the coating of aerosols with substances such as sulfate or organic carbon during daylight hours, but such coating appears to be limited or absent at night. Evidence for this is provided by scanning electron microscope images of aerosols collected at three sampling sites. During daylight hours the values of aABS did not increase with aerosol age for median ages in the range of 1-4 hours. There is some evidence for absorption increasing as aerosols were advected from T1 to T2 but the statistical significance of that result is not strong.

Doran, J. C.; Fast, Jerome D.; Barnard, James C.; Laskin, Alexander; Desyaterik, Yury; Gilles, Marry K.; Hopkins, Rebecca J.

2008-03-07T23:59:59.000Z

425

Methods and computer executable instructions for rapidly calculating simulated particle transport through geometrically modeled treatment volumes having uniform volume elements for use in radiotherapy  

DOE Patents (OSTI)

Methods and computer executable instructions are disclosed for ultimately developing a dosimetry plan for a treatment volume targeted for irradiation during cancer therapy. The dosimetry plan is available in "real-time" which especially enhances clinical use for in vivo applications. The real-time is achieved because of the novel geometric model constructed for the planned treatment volume which, in turn, allows for rapid calculations to be performed for simulated movements of particles along particle tracks there through. The particles are exemplary representations of neutrons emanating from a neutron source during BNCT. In a preferred embodiment, a medical image having a plurality of pixels of information representative of a treatment volume is obtained. The pixels are: (i) converted into a plurality of substantially uniform volume elements having substantially the same shape and volume of the pixels; and (ii) arranged into a geometric model of the treatment volume. An anatomical material associated with each uniform volume element is defined and stored. Thereafter, a movement of a particle along a particle track is defined through the geometric model along a primary direction of movement that begins in a starting element of the uniform volume elements and traverses to a next element of the uniform volume elements. The particle movement along the particle track is effectuated in integer based increments along the primary direction of movement until a position of intersection occurs that represents a condition where the anatomical material of the next element is substantially different from the anatomical material of the starting element. This position of intersection is then useful for indicating whether a neutron has been captured, scattered or exited from the geometric model. From this intersection, a distribution of radiation doses can be computed for use in the cancer therapy. The foregoing represents an advance in computational times by multiple factors of time magnitudes.

Frandsen, Michael W. (Helena, MT); Wessol, Daniel E. (Bozeman, MT); Wheeler, Floyd J. (Idaho Falls, ID)

2001-01-16T23:59:59.000Z

426

Submitted to Journal of Biomechanics, July 2008; in revised form May 2009. Statistical Osteoporosis Models Using  

E-Print Network (OSTI)

elements (CFE) can be used. The aim of the study is to test the potential of CFE. For that, a parameter in classical µFE models, composite finite elements (CFE) introduced in [HS97b, HS97a, HS98] can be used. A 3D removal. Compared to lattice models, the volume-based CFE approach permits a much better resolution

Rumpf, Martin

427

Finite-Difference Modeling of Noise Coupling between Power/Ground Planes in Multilayered Packages and Boards  

E-Print Network (OSTI)

system become increasingly more critical regarding the signal integrity and electromagnetic interference electromagnetic interference. Hence, accurate modeling of power/ground planes is critical to estimate the noise

Swaminathan, Madhavan

428

TRISO-Fuel Element Performance Modeling for the Hybrid LIFE Engine with Pu Fuel Blanket  

SciTech Connect

A TRISO-coated fuel thermo-mechanical performance study is performed for the hybrid LIFE engine to test the viability of TRISO particles to achieve ultra-high burnup of a weapons-grade Pu blanket. Our methodology includes full elastic anisotropy, time and temperature varying material properties for all TRISO layers, and a procedure to remap the elastic solutions in order to achieve fast fluences up to 30 x 10{sup 25} n {center_dot} m{sup -2} (E > 0.18 MeV). In order to model fast fluences in the range of {approx} 7 {approx} 30 x 10{sup 25} n {center_dot} m{sup -2}, for which no data exist, careful scalings and extrapolations of the known TRISO material properties are carried out under a number of potential scenarios. A number of findings can be extracted from our study. First, failure of the internal pyrolytic carbon (PyC) layer occurs within the first two months of operation. Then, the particles behave as BISO-coated particles, with the internal pressure being withstood directly by the SiC layer. Later, after 1.6 years, the remaining PyC crumbles due to void swelling and the fuel particle becomes a single-SiC-layer particle. Unrestrained by the PyC layers, and at the temperatures and fluences in the LIFE engine, the SiC layer maintains reasonably-low tensile stresses until the end-of-life. Second, the PyC creep constant, K, has a striking influence on the fuel performance of TRISO-coated particles, whose stresses scale almost inversely proportional to K. Obtaining more reliable measurements, especially at higher fluences, is an imperative for the fidelity of our models. Finally, varying the geometry of the TRISO-coated fuel particles results in little differences in the scope of fuel performance. The mechanical integrity of 2-cm graphite pebbles that act as fuel matrix has also been studied and it is concluded that they can reliable serve the entire LIFE burnup cycle without failure.

DeMange, P; Marian, J; Caro, M; Caro, A

2010-02-18T23:59:59.000Z

429

Numerical modelling of the laser surface processing of magnesia partially stabilized zirconia by the means of three-dimensional transient finite element analysis  

Science Journals Connector (OSTI)

...beam with the lower power before and after...processing with high power to lower the thermal...laser beam with lower power in order to prevent...the rate of heat generation per unit volume...CO2 laser beam was fired and traversed across...pressure O2 process gas was used to shield...

2006-01-01T23:59:59.000Z

430

Microembossing of ultrafine grained Al: microstructural analysis and finite element modelling This article has been downloaded from IOPscience. Please scroll down to see the full text article.  

E-Print Network (OSTI)

@soton.ac.uk, jiuwenzh@yahoo.com.cn, zm@ecs.soton.ac.uk and mk1@ecs.soton.ac.uk Received 5 May 2010, in final form 19 July 2010 Published 1 September 2010 Online at stacks.iop.org/JMM/20/105002 Abstract Ultra

Southampton, University of

431

Nonlinear Analysis of Beams Using Least-Squares Finite Element Models Based on the Euler-Bernoulli and Timoshenko Beam Theories  

E-Print Network (OSTI)

} Residual Vector {T} Tangent Matrix ij? Cartesian Component of Stress Tensor ij? Cartesian Component of Strain Tensor e EW Work Done by External Forces e IW Work Done by Internal Forces xxS Shear Stiffness (GAKs) G Shear... ..... 6 2.3 Summary............................................................................................ 8 3. THEORETICAL FORMULATION OF EBT AND TBT ............................ 9 3.1 Background...

Raut, Ameeta A.

2010-07-14T23:59:59.000Z

432

Effects of densitometry, material mapping and load estimation uncertainties on the accuracy of patient-specific finite-element models of the scapula  

Science Journals Connector (OSTI)

...namely 90 abduction and 90 flexion, were applied on the geometry of the scapula as traction...movements. The boundary conditions were applied at three points within the bone geometry...strain distributions resulting from the applied musculoskeletal loads (figure 1 c) were...

2014-01-01T23:59:59.000Z

433

To cite this document: Pozzolini, Cdric and Buffe, Fabrice and Salan, Michel A localization and updating strategy of large finite element models in structural  

E-Print Network (OSTI)

Introduction During the launch of a satellite, the level of excitation is very high. However, the security frequencies. Finally we propose a global strategy and discuss the results we obtained on satellite JASON2. 1 to be correct when the Modal Assurance Criterion (MAC) is accurate enough. Centre National d'Etudes Spatiales

Mailhes, Corinne

434

E-Print Network 3.0 - anisotropic hexahedra finite Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

especially with respect to finite element... analyses within highly elastic, and plas- tic, structural domains. However, because hexahedral ... Source: Utah, University of -...

435

A Finite Landscape?  

E-Print Network (OSTI)

We present evidence that the number of string/$M$ theory vacua consistent with experiments is a finite number. We do this both by explicit analysis of infinite sequences of vacua and by applying various mathematical finiteness theorems.

Bobby S Acharya; Michael R Douglas

2006-06-21T23:59:59.000Z

436

Verification and Validation of EnergyPlus Conduction Finite Difference and Phase Change Material Models for Opaque Wall Assemblies  

SciTech Connect

Phase change materials (PCMs) represent a potential technology to reduce peak loads and HVAC energy consumption in buildings. There are few building energy simulation programs that have the capability to simulate PCM but their accuracy has not been completely tested. This report summarizes NREL efforts to develop diagnostic tests cases to obtain accurate energy simulations when PCMs are modeled in residential buildings.

Tabares-Velasco, P. C.; Christensen, C.; Bianchi, M.; Booten, C.

2012-07-01T23:59:59.000Z

437

It's Elemental - The Element Europium  

NLE Websites -- All DOE Office Websites (Extended Search)

Samarium Samarium Previous Element (Samarium) The Periodic Table of Elements Next Element (Gadolinium) Gadolinium The Element Europium [Click for Isotope Data] 63 Eu Europium 151.964 Atomic Number: 63 Atomic Weight: 151.964 Melting Point: 1095 K (822°C or 1512°F) Boiling Point: 1802 K (1529°C or 2784°F) Density: 5.24 grams per cubic centimeter Phase at Room Temperature: Solid Element Classification: Metal Period Number: 6 Group Number: none Group Name: Lanthanide What's in a name? Named after the continent of Europe. Say what? Europium is pronounced as yoo-RO-pee-em. History and Uses: Europium was discovered by Eugène-Antole Demarçay, a French chemist, in 1896. Demarçay suspected that samples of a recently discovered element, samarium, were contaminated with an unknown element. He was able to produce

438

It's Elemental - The Element Potassium  

NLE Websites -- All DOE Office Websites (Extended Search)

Argon Argon Previous Element (Argon) The Periodic Table of Elements Next Element (Calcium) Calcium The Element Potassium [Click for Isotope Data] 19 K Potassium 39.0983 Atomic Number: 19 Atomic Weight: 39.0983 Melting Point: 336.53 K (63.38°C or 146.08°F) Boiling Point: 1032 K (759°C or 1398°F) Density: 0.89 grams per cubic centimeter Phase at Room Temperature: Solid Element Classification: Metal Period Number: 4 Group Number: 1 Group Name: Alkali Metal What's in a name? From the English word potash. Potassium's chemical symbol comes from the Latin word for alkali, kalium. Say what? Potassium is pronounced as poh-TASS-ee-em. History and Uses: Although potassium is the eighth most abundant element on earth and comprises about 2.1% of the earth's crust, it is a very reactive element

439

It's Elemental - The Element Sulfur  

NLE Websites -- All DOE Office Websites (Extended Search)

Phosphorus Phosphorus Previous Element (Phosphorus) The Periodic Table of Elements Next Element (Chlorine) Chlorine The Element Sulfur [Click for Isotope Data] 16 S Sulfur 32.065 Atomic Number: 16 Atomic Weight: 32.065 Melting Point: 388.36 K (115.21°C or 239.38°F) Boiling Point: 717.75 K (444.60°C or 832.28°F) Density: 2.067 grams per cubic centimeter Phase at Room Temperature: Solid Element Classification: Non-metal Period Number: 3 Group Number: 16 Group Name: Chalcogen What's in a name? From the Sanskrit word sulvere and the Latin word sulphurium. Say what? Sulfur is pronounced as SUL-fer. History and Uses: Sulfur, the tenth most abundant element in the universe, has been known since ancient times. Sometime around 1777, Antoine Lavoisier convinced the rest of the scientific community that sulfur was an element. Sulfur is a

440

It's Elemental - The Element Magnesium  

NLE Websites -- All DOE Office Websites (Extended Search)

Sodium Sodium Previous Element (Sodium) The Periodic Table of Elements Next Element (Aluminum) Aluminum The Element Magnesium [Click for Isotope Data] 12 Mg Magnesium 24.3050 Atomic Number: 12 Atomic Weight: 24.3050 Melting Point: 923 K (650°C or 1202°F) Boiling Point: 1363 K (1090°C or 1994°F) Density: 1.74 grams per cubic centimeter Phase at Room Temperature: Solid Element Classification: Metal Period Number: 3 Group Number: 2 Group Name: Alkaline Earth Metal What's in a name? For Magnesia, a district in the region of Thessaly, Greece. Say what? Magnesium is pronounced as mag-NEE-zhi-em. History and Uses: Although it is the eighth most abundant element in the universe and the seventh most abundant element in the earth's crust, magnesium is never found free in nature. Magnesium was first isolated by Sir Humphry Davy, an

Note: This page contains sample records for the topic "modeling finite element" 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

Extremality of translation-invariant phases for a finite-state SOS-model on the binary tree  

E-Print Network (OSTI)

We consider the SOS (solid-on-solid) model, with spin values $0,1,2$, on the Cayley tree of order two (binary tree). We treat both ferromagnetic and antiferromagnetic coupling, with interactions which are proportional to the absolute value of the spin differences. We present a classification of all translation-invariant phases (splitting Gibbs measures) of the model: We show uniqueness in the case of antiferromagnetic interactions, and existence of up to seven phases in the case of ferromagnetic interactions, where the number of phases depends on the interaction strength. Next we investigate whether these states are extremal or non-extremal in the set of all Gibbs measures, when the coupling strength is varied, whenever they exist. We show that two states are always extremal, two states are always non-extremal, while three of the seven states make transitions between extremality and non-extremality. We provide explicit bounds on those transition values, making use of algebraic properties of the models, and an adaptation of the method of Martinelli, Sinclair, Weitz.

C. Kuelske; U. A. Rozikov

2014-11-21T23:59:59.000Z

442

Challenges in Continuum Modelling of Intergranular Fracture  

E-Print Network (OSTI)

Challenges in Continuum Modelling of Intergranular Fracture V. R. Coffman*, J. P. Sethna , A. R-2501, USA Cornell Fracture Group, Rhodes Hall, Cornell University, Ithaca, NY 14853-2501, USA § Department fracture in polycrystals is often simulated by finite elements coupled to a cohesive zone model

Sethna, James P.

443

Quantum-electrodynamic model of the finite-size electron and calculation of the fine-structure constant  

E-Print Network (OSTI)

We propose a model of a relativistic string formed by a scalar complex field, acting as electromagnetic field source. An axiosymmetric solutions of the stationary equations for the scalar and electromagnetic fields are found numerically. The mass $m$ is calculated as a function of the charge $e$ and the magnetic moment $\\mu$ of the system. The resulting toroidal structure is interpreted as an electron because the calculated ratio $e^3/(2mc^2\\mu)$ coincides with the fine-structure constant $\\alpha=e^2/(\\hbar c)\\approx e^3/(2m_ec^2\\mu_e)$.

E. P. Likhtman

2006-11-05T23:59:59.000Z

444

VARIATIONAL BOUSSINESQ MODEL FOR SIMULATION OF COASTAL WAVES AND TSUNAMIS  

E-Print Network (OSTI)

1 VARIATIONAL BOUSSINESQ MODEL FOR SIMULATION OF COASTAL WAVES AND TSUNAMIS DIDIT ADYTIA E. VAN, Enschede, Netherlands In this paper we describe the basic ideas of a so-called Variational Boussinesq Model the background of a Variational Boussinesq Model (VBM) and a finite element implementation for coastal waves

Al Hanbali, Ahmad

445

Modeling Cylinder Valve in Hydrogen Fuel Cell Car  

Science Journals Connector (OSTI)

We develop a fast alternative to a complex finite element analysis (FEA) model of cylinder valve in hydrogen fuel cell car based on support vector machine (SVM). The inputs of model are shape parameters of core and plunger of the valve, and the output ... Keywords: modeling, cylinder valve, SVM, uniform design

Liang Yu; Shengnian Cai; Wang Na

2011-03-01T23:59:59.000Z

446

Modeling gas flow through microchannels and nanopores Subrata Roya)  

E-Print Network (OSTI)

Modeling gas flow through microchannels and nanopores Subrata Roya) and Reni Raju Computational. A two-dimensional finite-element based microscale flow model is developed to efficiently predict is modeled using either the continuum or the molecular approach.1­4 The con- tinuum approach solves

Roy, Subrata

447

It's Elemental - The Element Nitrogen  

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Carbon Carbon Previous Element (Carbon) The Periodic Table of Elements Next Element (Oxygen) Oxygen The Element Nitrogen [Click for Isotope Data] 7 N Nitrogen 14.0067 Atomic Number: 7 Atomic Weight: 14.0067 Melting Point: 63.15 K (-210.00°C or -346.00°F) Boiling Point: 77.36 K (-195.79°C or -320.44°F) Density: 0.0012506 grams per cubic centimeter Phase at Room Temperature: Gas Element Classification: Non-metal Period Number: 2 Group Number: 15 Group Name: Pnictogen What's in a name? From the Greek words nitron and genes, which together mean "saltpetre forming." Say what? Nitrogen is pronounced as NYE-treh-gen. History and Uses: Nitrogen was discovered by the Scottish physician Daniel Rutherford in 1772. It is the fifth most abundant element in the universe and makes up

448

It's Elemental - The Element Sodium  

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Neon Neon Previous Element (Neon) The Periodic Table of Elements Next Element (Magnesium) Magnesium The Element Sodium [Click for Isotope Data] 11 Na Sodium 22.98976928 Atomic Number: 11 Atomic Weight: 22.98976928 Melting Point: 370.95 K (97.80°C or 208.04°F) Boiling Point: 1156 K (883°C or 1621°F) Density: 0.97 grams per cubic centimeter Phase at Room Temperature: Solid Element Classification: Metal Period Number: 3 Group Number: 1 Group Name: Alkali Metal What's in a name? From the English word soda and from the Medieval Latin word sodanum, which means "headache remedy." Sodium's chemical symbol comes from the Latin word for sodium carbonate, natrium. Say what? Sodium is pronounced as SO-dee-em. History and Uses: Although sodium is the sixth most abundant element on earth and comprises

449

It's Elemental - The Element Francium  

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Radon Radon Previous Element (Radon) The Periodic Table of Elements Next Element (Radium) Radium The Element Francium [Click for Isotope Data] 87 Fr Francium 223 Atomic Number: 87 Atomic Weight: 223 Melting Point: 300 K (27°C or 81°F) Boiling Point: Unknown Density: Unknown Phase at Room Temperature: Solid Element Classification: Metal Period Number: 7 Group Number: 1 Group Name: Alkali Metal Radioactive What's in a name? Named for the country of France. Say what? Francium is pronounced as FRAN-see-em. History and Uses: Francium was discovered by Marguerite Catherine Perey, a French chemist, in 1939 while analyzing actinium's decay sequence. Although considered a natural element, scientists estimate that there is no more than one ounce of francium in the earth's crust at one time. Since there is so little

450

It's Elemental - The Element Phosphorus  

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Silicon Silicon Previous Element (Silicon) The Periodic Table of Elements Next Element (Sulfur) Sulfur The Element Phosphorus [Click for Isotope Data] 15 P Phosphorus 30.973762 Atomic Number: 15 Atomic Weight: 30.973762 Melting Point: 317.30 K (44.15°C or 111.47°F) Boiling Point: 553.65 K (280.5°C or 536.9°F) Density: 1.82 grams per cubic centimeter Phase at Room Temperature: Solid Element Classification: Non-metal Period Number: 3 Group Number: 15 Group Name: Pnictogen What's in a name? From the Greek word for light bearing, phosphoros. Say what? Phosphorus is pronounced as FOS-fer-es. History and Uses: In what is perhaps the most disgusting method of discovering an element, phosphorus was first isolated in 1669 by Hennig Brand, a German physician and alchemist, by boiling, filtering and otherwise processing as many as 60

451

It's Elemental - The Element Cerium  

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Lanthanum Lanthanum Previous Element (Lanthanum) The Periodic Table of Elements Next Element (Praseodymium) Praseodymium The Element Cerium [Click for Isotope Data] 58 Ce Cerium 140.116 Atomic Number: 58 Atomic Weight: 140.116 Melting Point: 1071 K (798°C or 1468°F) Boiling Point: 3697 K (3424°C or 6195°F) Density: 6.770 grams per cubic centimeter Phase at Room Temperature: Solid Element Classification: Metal Period Number: 6 Group Number: none Group Name: Lanthanide What's in a name? Named for the asteroid Ceres. Say what? Cerium is pronounced as SER-ee-em. History and Uses: Cerium was discovered by Jöns Jacob Berzelius and Wilhelm von Hisinger, Swedish chemists, and independently by Martin Heinrich Klaproth, a German chemist, in 1803. Cerium is the most abundant of the rare earth elements

452

It's Elemental - The Element Indium  

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Cadmium Cadmium Previous Element (Cadmium) The Periodic Table of Elements Next Element (Tin) Tin The Element Indium [Click for Isotope Data] 49 In Indium 114.818 Atomic Number: 49 Atomic Weight: 114.818 Melting Point: 429.75 K (156.60°C or 313.88°F) Boiling Point: 2345 K (2072°C or 3762°F) Density: 7.31 grams per cubic centimeter Phase at Room Temperature: Solid Element Classification: Metal Period Number: 5 Group Number: 13 Group Name: none What's in a name? Named after the bright indigo line in its spectrum. Say what? Indium is pronounced as IN-dee-em. History and Uses: Indium was discovered by the German chemists Ferdinand Reich and Hieronymus Theodor Richter in 1863. Reich and Richter had been looking for traces of the element thallium in samples of zinc ores. A brilliant indigo line in

453

It's Elemental - The Element Neon  

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Fluorine Fluorine Previous Element (Fluorine) The Periodic Table of Elements Next Element (Sodium) Sodium The Element Neon [Click for Isotope Data] 10 Ne Neon 20.1797 Atomic Number: 10 Atomic Weight: 20.1797 Melting Point: 24.56 K (-248.59°C or -415.46°F) Boiling Point: 27.07 K (-246.08°C or -410.94°F) Density: 0.0008999 grams per cubic centimeter Phase at Room Temperature: Gas Element Classification: Non-metal Period Number: 2 Group Number: 18 Group Name: Noble Gas What's in a name? From the Greek word for new, neos. Say what? Neon is pronounced as NEE-on. History and Uses: Neon was discovered by Sir William Ramsay, a Scottish chemist, and Morris M. Travers, an English chemist, shortly after their discovery of the element krypton in 1898. Like krypton, neon was discovered through the

454

It's Elemental - The Element Technetium  

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Molybdenum Molybdenum Previous Element (Molybdenum) The Periodic Table of Elements Next Element (Ruthenium) Ruthenium The Element Technetium [Click for Isotope Data] 43 Tc Technetium 98 Atomic Number: 43 Atomic Weight: 98 Melting Point: 2430 K (2157°C or 3915°F) Boiling Point: 4538 K (4265°C or 7709°F) Density: 11 grams per cubic centimeter Phase at Room Temperature: Solid Element Classification: Metal Period Number: 5 Group Number: 7 Group Name: none Radioactive and Artificially Produced What's in a name? From the Greek word for artificial, technetos. Say what? Technetium is pronounced as tek-NEE-she-em. History and Uses: Technetium was the first artificially produced element. It was isolated by Carlo Perrier and Emilio Segrè in 1937. Technetium was created by bombarding molybdenum atoms with deuterons that had been accelerated by a

455

It's Elemental - The Element Cobalt  

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Iron Iron Previous Element (Iron) The Periodic Table of Elements Next Element (Nickel) Nickel The Element Cobalt [Click for Isotope Data] 27 Co Cobalt 58.933195 Atomic Number: 27 Atomic Weight: 58.933195 Melting Point: 1768 K (1495°C or 2723°F) Boiling Point: 3200 K (2927°C or 5301°F) Density: 8.86 grams per cubic centimeter Phase at Room Temperature: Solid Element Classification: Metal Period Number: 4 Group Number: 9 Group Name: none What's in a name? From the German word for goblin or evil spirit, kobald and the Greek word for mine, cobalos. Say what? Cobalt is pronounced as KO-bolt. History and Uses: Cobalt was discovered by Georg Brandt, a Swedish chemist, in 1739. Brandt was attempting to prove that the ability of certain minerals to color glass blue was due to an unknown element and not to bismuth, as was commonly

456

It's Elemental - The Element Bromine  

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Selenium Selenium Previous Element (Selenium) The Periodic Table of Elements Next Element (Krypton) Krypton The Element Bromine [Click for Isotope Data] 35 Br Bromine 79.904 Atomic Number: 35 Atomic Weight: 79.904 Melting Point: 265.95 K (-7.2°C or 19.0°F) Boiling Point: 331.95 K (58.8°C or 137.8°F) Density: 3.11 grams per cubic centimeter Phase at Room Temperature: Liquid Element Classification: Non-metal Period Number: 4 Group Number: 17 Group Name: Halogen What's in a name? From the Greek word for stench, bromos. Say what? Bromine is pronounced as BRO-meen. History and Uses: The only nonmetallic element that is a liquid at normal room temperatures, bromine was produced by Carl Löwig, a young chemistry student, the summer before starting his freshman year at Heidelberg. When he showed his

457

It's Elemental - The Element Oxygen  

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Nitrogen Nitrogen Previous Element (Nitrogen) The Periodic Table of Elements Next Element (Fluorine) Fluorine The Element Oxygen [Click for Isotope Data] 8 O Oxygen 15.9994 Atomic Number: 8 Atomic Weight: 15.9994 Melting Point: 54.36 K (-218.79°C or -361.82°F) Boiling Point: 90.20 K (-182.95°C or -297.31°F) Density: 0.001429 grams per cubic centimeter Phase at Room Temperature: Gas Element Classification: Non-metal Period Number: 2 Group Number: 16 Group Name: Chalcogen What's in a name? From the greek words oxys and genes, which together mean "acid forming." Say what? Oxygen is pronounced as OK-si-jen. History and Uses: Oxygen had been produced by several chemists prior to its discovery in 1774, but they failed to recognize it as a distinct element. Joseph

458

It's Elemental - The Element Manganese  

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Chromium Chromium Previous Element (Chromium) The Periodic Table of Elements Next Element (Iron) Iron The Element Manganese [Click for Isotope Data] 25 Mn Manganese 54.938045 Atomic Number: 25 Atomic Weight: 54.938045 Melting Point: 1519 K (1246°C or 2275°F) Boiling Point: 2334 K (2061°C or 3742°F) Density: 7.3 grams per cubic centimeter Phase at Room Temperature: Solid Element Classification: Metal Period Number: 4 Group Number: 7 Group Name: none What's in a name? From the Latin word for magnet, magnes. Say what? Manganese is pronounced as MAN-ge-nees. History and Uses: Proposed to be an element by Carl Wilhelm Scheele in 1774, manganese was discovered by Johan Gottlieb Gahn, a Swedish chemist, by heating the mineral pyrolusite (MnO2) in the presence of charcoal later that year.

459

It's Elemental - The Element Titanium  

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Scandium Scandium Previous Element (Scandium) The Periodic Table of Elements Next Element (Vanadium) Vanadium The Element Titanium [Click for Isotope Data] 22 Ti Titanium 47.867 Atomic Number: 22 Atomic Weight: 47.867 Melting Point: 1941 K (1668°C or 3034°F) Boiling Point: 3560 K (3287°C or 5949°F) Density: 4.5 grams per cubic centimeter Phase at Room Temperature: Solid Element Classification: Metal Period Number: 4 Group Number: 4 Group Name: none What's in a name? From the Greek word Titans, the mythological "first sons of the Earth." Say what? Titanium is pronounced as tie-TAY-nee-em. History and Uses: Titanium was discovered in 1791 by the Reverend William Gregor, an English pastor. Pure titanium was first produced by Matthew A. Hunter, an American metallurgist, in 1910. Titanium is the ninth most abundant element in the

460

Finiteness properties and profinite completions  

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......finite or of finite index, [14, Chapter...PROPERTIES AND PROFINITE COMPLETIONS 107 Finally, by...every finite index subgroup of a finitely...the profinite completion of a finitely generated...for every finite index subgroup...same pronilpotent completion they also have the......

Alexander Lubotzky

2014-02-01T23:59:59.000Z

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461

Understanding how low-income families prioritize elements of health care access for their children via the optimal care model  

Science Journals Connector (OSTI)

Insurance coverage alone does not guarantee access to needed health care. Few studies have explored what “access” means to low-income families, nor have they examined how elements of access are prioritized whe...

Heather Angier; Jessica Gregg; Rachel Gold…

2014-11-01T23:59:59.000Z

462

It's Elemental - The Element Astatine  

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Polonium Polonium Previous Element (Polonium) The Periodic Table of Elements Next Element (Radon) Radon The Element Astatine [Click for Isotope Data] 85 At Astatine 210 Atomic Number: 85 Atomic Weight: 210 Melting Point: 575 K (302°C or 576°F) Boiling Point: Unknown Density: about 7 grams per cubic centimeter Phase at Room Temperature: Solid Element Classification: Semi-metal Period Number: 6 Group Number: 17 Group Name: Halogen Radioactive What's in a name? From the Greek word for unstable, astatos. Say what? Astatine is pronounced as AS-teh-teen or as AS-teh-ten. History and Uses: Astatine was produced by Dale R. Carson, K.R. MacKenzie and Emilio Segrè by bombarding an isotope of bismuth, bismuth-209, with alpha particles that had been accelerated in a device called a cyclotron. This created

463

It's Elemental - The Element Copper  

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Nickel Nickel Previous Element (Nickel) The Periodic Table of Elements Next Element (Zinc) Zinc The Element Copper [Click for Isotope Data] 29 Cu Copper 63.546 Atomic Number: 29 Atomic Weight: 63.546 Melting Point: 1357.77 K (1084.62°C or 1984.32°F) Boiling Point: 2835 K (2562°C or 4644°F) Density: 8.933 grams per cubic centimeter Phase at Room Temperature: Solid Element Classification: Metal Period Number: 4 Group Number: 11 Group Name: none What's in a name? From the Latin word cuprum, which means "from the island of Cyprus." Say what? Copper is pronounced as KOP-er. History and Uses: Archaeological evidence suggests that people have been using copper for at least 11,000 years. Relatively easy to mine and refine, people discovered methods for extracting copper from its ores at least 7,000 years ago. The

464

It's Elemental - The Element Gadolinium  

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Europium Europium Previous Element (Europium) The Periodic Table of Elements Next Element (Terbium) Terbium The Element Gadolinium [Click for Isotope Data] 64 Gd Gadolinium 157.25 Atomic Number: 64 Atomic Weight: 157.25 Melting Point: 1586 K (1313°C or 2395°F) Boiling Point: 3546 K (3273°C or 5923°F) Density: 7.90 grams per cubic centimeter Phase at Room Temperature: Solid Element Classification: Metal Period Number: 6 Group Number: none Group Name: Lanthanide What's in a name? Named for the mineral gadolinite which was named after Johan Gadolin, a Finnish chemist. Say what? Gadolinium is pronounced as GAD-oh-LIN-ee-em. History and Uses: Spectroscopic evidence for the existence of gadolinium was first observed by the Swiss chemist Jean Charles Galissard de Marignac in the minerals

465

It's Elemental - The Element Mercury  

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Gold Gold Previous Element (Gold) The Periodic Table of Elements Next Element (Thallium) Thallium The Element Mercury [Click for Isotope Data] 80 Hg Mercury 200.59 Atomic Number: 80 Atomic Weight: 200.59 Melting Point: 234.32 K (-38.83°C or -37.89°F) Boiling Point: 629.88 K (356.73°C or 674.11°F) Density: 13.5336 grams per cubic centimeter Phase at Room Temperature: Liquid Element Classification: Metal Period Number: 6 Group Number: 12 Group Name: none What's in a name? Named after the planet Mercury. Mercury's chemical symbol comes from the Greek word hydrargyrum, which means "liquid silver." Say what? Mercury is pronounced as MER-kyoo-ree. History and Uses: Mercury was known to the ancient Chinese and Hindus and has been found in 3500 year old Egyptian tombs. Mercury is not usually found free in nature

466

It's Elemental - The Element Hafnium  

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Lutetium Lutetium Previous Element (Lutetium) The Periodic Table of Elements Next Element (Tantalum) Tantalum The Element Hafnium [Click for Isotope Data] 72 Hf Hafnium 178.49 Atomic Number: 72 Atomic Weight: 178.49 Melting Point: 2506 K (2233°C or 4051°F) Boiling Point: 4876 K (4603°C or 8317°F) Density: 13.3 grams per cubic centimeter Phase at Room Temperature: Solid Element Classification: Metal Period Number: 6 Group Number: 4 Group Name: none What's in a name? From the Latin word for the city of Copenhagen, Hafnia. Say what? Hafnium is pronounced as HAF-neeem. History and Uses: Hafnium was discovered by Dirk Coster, a Danish chemist, and Charles de Hevesy, a Hungarian chemist, in 1923. They used a method known as X-ray spectroscopy to study the arrangement of the outer electrons of atoms in

467

It's Elemental - The Element Boron  

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Beryllium Beryllium Previous Element (Beryllium) The Periodic Table of Elements Next Element (Carbon) Carbon The Element Boron [Click for Isotope Data] 5 B Boron 10.811 Atomic Number: 5 Atomic Weight: 10.811 Melting Point: 2348 K (2075°C or 3767°F) Boiling Point: 4273 K (4000°C or 7232°F) Density: 2.37 grams per cubic centimeter Phase at Room Temperature: Solid Element Classification: Semi-metal Period Number: 2 Group Number: 13 Group Name: none What's in a name? From the Arabic word Buraq and the Persian word Burah, which are both words for the material "borax." Say what? Boron is pronounced as BO-ron. History and Uses: Boron was discovered by Joseph-Louis Gay-Lussac and Louis-Jaques Thénard, French chemists, and independently by Sir Humphry Davy, an English chemist,

468

It's Elemental - The Element Thorium  

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Actinium Actinium Previous Element (Actinium) The Periodic Table of Elements Next Element (Protactinium) Protactinium The Element Thorium [Click for Isotope Data] 90 Th Thorium 232.03806 Atomic Number: 90 Atomic Weight: 232.03806 Melting Point: 2023 K (1750°C or 3182°F) Boiling Point: 5061 K (4788°C or 8650°F) Density: 11.72 grams per cubic centimeter Phase at Room Temperature: Solid Element Classification: Metal Period Number: 7 Group Number: none Group Name: Actinide Radioactive What's in a name? Named for the Scandinavian god of war, Thor. Say what? Thorium is pronounced as THOR-ee-em or as THO-ree-em. History and Uses: Thorium was discovered by Jöns Jacob Berzelius, a Swedish chemist, in 1828. He discovered it in a sample of a mineral that was given to him by the Reverend Has Morten Thrane Esmark, who suspected that it contained an

469

It's Elemental - The Element Chromium  

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Vanadium Vanadium Previous Element (Vanadium) The Periodic Table of Elements Next Element (Manganese) Manganese The Element Chromium [Click for Isotope Data] 24 Cr Chromium 51.9961 Atomic Number: 24 Atomic Weight: 51.9961 Melting Point: 2180 K (1907°C or 3465°F) Boiling Point: 2944 K (2671°C or 4840°F) Density: 7.15 grams per cubic centimeter Phase at Room Temperature: Solid Element Classification: Metal Period Number: 4 Group Number: 6 Group Name: none What's in a name? From the Greek word for color, chroma. Say what? Chromium is pronounced as KROH-mee-em. History and Uses: Chromium was discovered by Louis-Nicholas Vauquelin while experimenting with a material known as Siberian red lead, also known as the mineral crocoite (PbCrO4), in 1797. He produced chromium oxide (CrO3) by mixing

470

It's Elemental - The Element Iron  

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Manganese Manganese Previous Element (Manganese) The Periodic Table of Elements Next Element (Cobalt) Cobalt The Element Iron [Click for Isotope Data] 26 Fe Iron 55.845 Atomic Number: 26 Atomic Weight: 55.845 Melting Point: 1811 K (1538°C or 2800°F) Boiling Point: 3134 K (2861°C or 5182°F) Density: 7.874 grams per cubic centimeter Phase at Room Temperature: Solid Element Classification: Metal Period Number: 4 Group Number: 8 Group Name: none What's in a name? From the Anglo-Saxon word iron. Iron's chemical symbol comes from the Latin word for iron, ferrum. Say what? Iron is pronounced as EYE-ern. History and Uses: Archaeological evidence suggests that people have been using iron for at least 5000 years. Iron is the cheapest and one of the most abundant of all metals, comprising nearly 5.6% of the earth's crust and nearly all of the

471

It's Elemental - The Element Molybdenum  

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Niobium Niobium Previous Element (Niobium) The Periodic Table of Elements Next Element (Technetium) Technetium The Element Molybdenum [Click for Isotope Data] 42 Mo Molybdenum 95.96 Atomic Number: 42 Atomic Weight: 95.96 Melting Point: 2896 K (2623°C or 4753°F) Boiling Point: 4912 K (4639°C or 8382°F) Density: 10.2 grams per cubic centimeter Phase at Room Temperature: Solid Element Classification: Metal Period Number: 5 Group Number: 6 Group Name: none What's in a name? From the Greek word for lead, molybdos. Say what? Molybdenum is pronounced as meh-LIB-deh-nem. History and Uses: Molybdenum was discovered by Carl Welhelm Scheele, a Swedish chemist, in 1778 in a mineral known as molybdenite (MoS2) which had been confused as a lead compound. Molybdenum was isolated by Peter Jacob Hjelm in 1781. Today,

472

It's Elemental - The Element Cesium  

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Xenon Xenon Previous Element (Xenon) The Periodic Table of Elements Next Element (Barium) Barium The Element Cesium [Click for Isotope Data] 55 Cs Cesium 132.9054519 Atomic Number: 55 Atomic Weight: 132.9054519 Melting Point: 301.59 K (28.44°C or 83.19°F) Boiling Point: 944 K (671°C or 1240°F) Density: 1.93 grams per cubic centimeter Phase at Room Temperature: Solid Element Classification: Metal Period Number: 6 Group Number: 1 Group Name: Alkali Metal What's in a name? From the Latin word for sky blue, caesius. Say what? Cesium is pronounced as SEE-zee-em. History and Uses: Cesium was discovered by Robert Wilhelm Bunsen and Gustav Robert Kirchhoff, German chemists, in 1860 through the spectroscopic analysis of Durkheim mineral water. They named cesium after the blue lines they observed in its

473

It's Elemental - The Element Iridium  

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Osmium Osmium Previous Element (Osmium) The Periodic Table of Elements Next Element (Platinum) Platinum The Element Iridium [Click for Isotope Data] 77 Ir Iridium 192.217 Atomic Number: 77 Atomic Weight: 192.217 Melting Point: 2719 K (2446°C or 4435°F) Boiling Point: 4701 K (4428°C or 8002°F) Density: 22.42 grams per cubic centimeter Phase at Room Temperature: Solid Element Classification: Metal Period Number: 6 Group Number: 9 Group Name: none What's in a name? From the Latin word for rainbow, iris. Say what? Iridium is pronounced as i-RID-ee-em. History and Uses: Iridium and osmium were discovered at the same time by the British chemist Smithson Tennant in 1803. Iridium and osmium were identified in the black residue remaining after dissolving platinum ore with aqua regia, a mixture

474

It's Elemental - The Element Platinum  

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Iridium Iridium Previous Element (Iridium) The Periodic Table of Elements Next Element (Gold) Gold The Element Platinum [Click for Isotope Data] 78 Pt Platinum 195.084 Atomic Number: 78 Atomic Weight: 195.084 Melting Point: 2041.55 K (1768.4°C or 3215.1°F) Boiling Point: 4098 K (3825°C or 6917°F) Density: 21.46 grams per cubic centimeter Phase at Room Temperature: Solid Element Classification: Metal Period Number: 6 Group Number: 10 Group Name: none What's in a name? From the Spainsh word for silver, platina. Say what? Platinum is pronounced as PLAT-en-em. History and Uses: Used by the pre-Columbian Indians of South America, platinum wasn't noticed by western scientists until 1735. Platinum can occur free in nature and is sometimes found in deposits of gold-bearing sands, primarily those found in

475

It's Elemental - The Element Arsenic  

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Germanium Germanium Previous Element (Germanium) The Periodic Table of Elements Next Element (Selenium) Selenium The Element Arsenic [Click for Isotope Data] 33 As Arsenic 74.92160 Atomic Number: 33 Atomic Weight: 74.92160 Melting Point: 1090 K (817°C or 1503°F) Boiling Point: 887 K (614°C or 1137°F) Density: 5.776 grams per cubic centimeter Phase at Room Temperature: Solid Element Classification: Semi-metal Period Number: 4 Group Number: 15 Group Name: Pnictogen What's in a name? From the Latin word arsenicum, the Greek word arsenikon and the Arabic word Az-zernikh. Say what? Arsenic is pronounced as AR-s'n-ik. History and Uses: Although arsenic compounds were mined by the early Chinese, Greek and Egyptian civilizations, it is believed that arsenic itself was first identified by Albertus Magnus, a German alchemist, in 1250. Arsenic occurs

476

It's Elemental - The Element Barium  

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Cesium Cesium Previous Element (Cesium) The Periodic Table of Elements Next Element (Lanthanum) Lanthanum The Element Barium [Click for Isotope Data] 56 Ba Barium 137.327 Atomic Number: 56 Atomic Weight: 137.327 Melting Point: 1000 K (727°C or 1341°F) Boiling Point: 2170 K (1897°C or 3447°F) Density: 3.62 grams per cubic centimeter Phase at Room Temperature: Solid Element Classification: Metal Period Number: 6 Group Number: 2 Group Name: Alkaline Earth Metal What's in a name? From the Greek word for heavy, barys. Say what? Barium is pronounced as BAR-ee-em. History and Uses: Barium was first isolated by Sir Humphry Davy, an English chemist, in 1808 through the electrolysis of molten baryta (BaO). Barium is never found free in nature since it reacts with oxygen in the air, forming barium oxide

477

It's Elemental - The Element Gold  

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Platinum Platinum Previous Element (Platinum) The Periodic Table of Elements Next Element (Mercury) Mercury The Element Gold [Click for Isotope Data] 79 Au Gold 196.966569 Atomic Number: 79 Atomic Weight: 196.966569 Melting Point: 1337.33 K (1064.18°C or 1947.52°F) Boiling Point: 3129 K (2856°C or 5173°F) Density: 19.282 grams per cubic centimeter Phase at Room Temperature: Solid Element Classification: Metal Period Number: 6 Group Number: 11 Group Name: none What's in a name? From the Sanskrit word Jval and the Anglo-Saxon word gold. Gold's chemical symbol comes from the the latin word for gold, aurum. Say what? Gold is pronounced as GOLD. History and Uses: An attractive and highly valued metal, gold has been known for at least 5500 years. Gold is sometimes found free in nature but it is usually found

478

It's Elemental - The Element Rhenium  

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Tungsten Tungsten Previous Element (Tungsten) The Periodic Table of Elements Next Element (Osmium) Osmium The Element Rhenium [Click for Isotope Data] 75 Re Rhenium 186.207 Atomic Number: 75 Atomic Weight: 186.207 Melting Point: 3459 K (3186°C or 5767°F) Boiling Point: 5869 K (5596°C or 10105°F) Density: 20.8 grams per cubic centimeter Phase at Room Temperature: Solid Element Classification: Metal Period Number: 6 Group Number: 7 Group Name: none What's in a name? From the Latin word for the Rhine River, Rhenus. Say what? Rhenium is pronounced as REE-nee-em. History and Uses: Rhenium was discovered by the German chemists Ida Tacke-Noddack, Walter Noddack and Otto Carl Berg in 1925. They detected rhenium spectroscopically in platinum ores and in the minerals columbite ((Fe, Mn, Mg)(Nb, Ta)2O6),

479

It's Elemental - The Element Osmium  

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Rhenium Rhenium Previous Element (Rhenium) The Periodic Table of Elements Next Element (Iridium) Iridium The Element Osmium [Click for Isotope Data] 76 Os Osmium 190.23 Atomic Number: 76 Atomic Weight: 190.23 Melting Point: 3306 K (3033°C or 5491°F) Boiling Point: 5285 K (5012°C or 9054°F) Density: 22.57 grams per cubic centimeter Phase at Room Temperature: Solid Element Classification: Metal Period Number: 6 Group Number: 8 Group Name: none What's in a name? From the Greek word for a smell, osme. Say what? Osmium is pronounced as OZ-mee-em. History and Uses: Osmium and iridium were discovered at the same time by the British chemist Smithson Tennant in 1803. Osmium and iridium were identified in the black residue remaining after dissolving platinum ore with aqua regia, a mixture

480

It's Elemental - The Element Antimony  

NLE Websites -- All DOE Office Websites (Extended Search)

Tin Tin Previous Element (Tin) The Periodic Table of Elements Next Element (Tellurium) Tellurium The Element Antimony [Click for Isotope Data] 51 Sb Antimony 121.760 Atomic Number: 51 Atomic Weight: 121.760 Melting Point: 903.78 K (630.63°C or 1167.13°F) Boiling Point: 1860 K (1587°C or 2889°F) Density: 6.685 grams per cubic centimeter Phase at Room Temperature: Solid Element Classification: Semi-metal Period Number: 5 Group Number: 15 Group Name: Pnictogen What's in a name? From the Greek words anti and monos, which together mean "not alone." Antimony's chemical symbol comes from its historic name, Stibium. Say what? Antimony is pronounced as AN-the-MOH-nee. History and Uses: Antimony has been known since ancient times. It is sometimes found free in nature, but is usually obtained from the ores stibnite (Sb2S3) and

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481

It's Elemental - The Element Zinc  

NLE Websites -- All DOE Office Websites (Extended Search)

Copper Copper Previous Element (Copper) The Periodic Table of Elements Next Element (Gallium) Gallium The Element Zinc [Click for Isotope Data] 30 Zn Zinc 65.38 Atomic Number: 30 Atomic Weight: 65.38 Melting Point: 692.68 K (419.53°C or 787.15°F) Boiling Point: 1180 K (907°C or 1665°F) Density: 7.134 grams per cubic centimeter Phase at Room Temperature: Solid Element Classification: Metal Period Number: 4 Group Number: 12 Group Name: none What's in a name? From the German word zink. Say what? Zinc is pronounced as ZINK. History and Uses: Although zinc compounds have been used for at least 2,500 years in the production of brass, zinc wasn't recognized as a distinct element until much later. Metallic zinc was first produced in India sometime in the 1400s by heating the mineral calamine (ZnCO3) with wool. Zinc was rediscovered by

482

It's Elemental - The Element Chlorine  

NLE Websites -- All DOE Office Websites (Extended Search)

Sulfur Sulfur Previous Element (Sulfur) The Periodic Table of Elements Next Element (Argon) Argon The Element Chlorine [Click for Isotope Data] 17 Cl Chlorine 35.453 Atomic Number: 17 Atomic Weight: 35.453 Melting Point: 171.65 K (-101.5°C or -150.7°F) Boiling Point: 239.11 K (-34.04°C or -29.27°F) Density: 0.003214 grams per cubic centimeter Phase at Room Temperature: Gas Element Classification: Non-metal Period Number: 3 Group Number: 17 Group Name: Halogen What's in a name? From the Greek word for greenish yellow, chloros. Say what? Chlorine is pronounced as KLOR-een or as KLOR-in. History and Uses: Since it combines directly with nearly every element, chlorine is never found free in nature. Chlorine was first produced by Carl Wilhelm Scheele, a Swedish chemist, when he combined the mineral pyrolusite (MnO2) with

483

It's Elemental - The Element Fluorine  

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Oxygen Oxygen Previous Element (Oxygen) The Periodic Table of Elements Next Element (Neon) Neon The Element Fluorine [Click for Isotope Data] 9 F Fluorine 18.9984032 Atomic Number: 9 Atomic Weight: 18.9984032 Melting Point: 53.53 K (-219.62°C or -363.32°F) Boiling Point: 85.03 K (-188.12°C or -306.62°F) Density: 0.001696 grams per cubic centimeter Phase at Room Temperature: Gas Element Classification: Non-metal Period Number: 2 Group Number: 17 Group Name: Halogen What's in a name? From the Latin and French words for flow, fluere. Say what? Fluorine is pronounced as FLU-eh-reen or as FLU-eh-rin. History and Uses: Fluorine is the most reactive of all elements and no chemical substance is capable of freeing fluorine from any of its compounds. For this reason, fluorine does not occur free in nature and was extremely difficult for

484

It's Elemental - The Element Lead  

NLE Websites -- All DOE Office Websites (Extended Search)

Thallium Thallium Previous Element (Thallium) The Periodic Table of Elements Next Element (Bismuth) Bismuth The Element Lead [Click for Isotope Data] 82 Pb Lead 207.2 Atomic Number: 82 Atomic Weight: 207.2 Melting Point: 600.61 K (327.46°C or 621.43°F) Boiling Point: 2022 K (1749°C or 3180°F) Density: 11.342 grams per cubic centimeter Phase at Room Temperature: Solid Element Classification: Metal Period Number: 6 Group Number: 14 Group Name: none What's in a name? From the Anglo-Saxon word lead. Lead's chemical symbol comes from the Latin word for waterworks, plumbum. Say what? Lead is pronounced as LED. History and Uses: Lead has been known since ancient times. It is sometimes found free in nature, but is usually obtained from the ores galena (PbS), anglesite (PbSO4), cerussite (PbCO3) and minum (Pb3O4). Although lead makes up only

485

It's Elemental - The Element Iodine  

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Tellurium Tellurium Previous Element (Tellurium) The Periodic Table of Elements Next Element (Xenon) Xenon The Element Iodine [Click for Isotope Data] 53 I Iodine 126.90447 Atomic Number: 53 Atomic Weight: 126.90447 Melting Point: 386.85 K (113.7°C or 236.7°F) Boiling Point: 457.55 K (184.4°C or 364.0°F) Density: 4.93 grams per cubic centimeter Phase at Room Temperature: Solid Element Classification: Non-metal Period Number: 5 Group Number: 17 Group Name: Halogen What's in a name? From the Greek word for violet, iodes. Say what? Iodine is pronounced as EYE-eh-dine or as EYE-eh-din. History and Uses: Iodine was discovered by the French chemist Barnard Courtois in 1811. Courtois was extracting sodium and potassium compounds from seaweed ash. Once these compounds were removed, he added sulfuric acid (H2SO4) to

486

Numerical modeling of mountain building: Interplay between erosion law and crustal rheology  

E-Print Network (OSTI)

Numerical modeling of mountain building: Interplay between erosion law and crustal rheology V. Cattin, and J. Lave´ (2004), Numerical modeling of mountain building: Interplay between erosion law by a 2D finite element model that incorporates the rheological layering of the crust and the main

Demouchy, Sylvie

487

Integrated thermal-microstructure model to predict the property gradients in resistance spot steel welds  

SciTech Connect

An integrated model approach was proposed for relating resistance welding parameters to weldment properties. An existing microstructure model was used to determine the microstructural and property gradients in resistance spot welds of plain carbon steel. The effect of these gradients on the weld integrity was evaluated with finite element analysis. Further modifications to this integrated thermal-microstructure model are discussed.

Babu, S.S.; Riemer, B.W.; Santella, M.L. [Oak Ridge National Lab., TN (United States); Feng, Z. [Edison Welding Inst., Columbus, OH (United States)

1998-11-01T23:59:59.000Z

488

SciDAC Center for Simulation of Wave-Plasma Interactions - Iterated Finite-Orbit Monte Carlo Simulations with Full-Wave Fields for Modeling Tokamak ICRF Wave Heating Experiments - Final Report  

SciTech Connect

This final report describes the work performed under U.S. Department of Energy Cooperative Agreement DE-FC02-08ER54954 for the period April 1, 2011 through March 31, 2013. The goal of this project was to perform iterated finite-orbit Monte Carlo simulations with full-wall fields for modeling tokamak ICRF wave heating experiments. In year 1, the finite-orbit Monte-Carlo code ORBIT-RF and its iteration algorithms with the full-wave code AORSA were improved to enable systematical study of the factors responsible for the discrepancy in the simulated and the measured fast-ion FIDA signals in the DIII-D and NSTX ICRF fast-wave (FW) experiments. In year 2, ORBIT-RF was coupled to the TORIC full-wave code for a comparative study of ORBIT-RF/TORIC and ORBIT-RF/AORSA results in FW experiments.

Choi, Myunghee [Retired] [Retired; Chan, Vincent S. [General Atomics] [General Atomics

2014-02-28T23:59:59.000Z

489

Finite N from Resurgent Large N  

E-Print Network (OSTI)

Due to instanton effects, gauge-theoretic large N expansions yield asymptotic series, in powers of 1/N^2. The present work shows how to generically make such expansions meaningful via their completion into resurgent transseries, encoding both perturbative and nonperturbative data. Large N resurgent transseries compute gauge-theoretic finite N results nonperturbatively (no matter how small N is). Explicit calculations are carried out within the gauge theory prototypical example of the quartic matrix model. Due to integrability in the matrix model, it is possible to analytically compute (fixed integer) finite N results. At the same time, the large N resurgent transseries for the free energy of this model was recently constructed. Together, it is shown how the resummation of the large N resurgent transseries matches the analytical finite N results up to remarkable numerical accuracy. Due to lack of Borel summability, Stokes phenomena has to be carefully taken into account, implying that instantons play a dominan...

Couso-Santamaría, Ricardo; Vaz, Ricardo

2015-01-01T23:59:59.000Z

490

A Comparison of Iterative Multilevel Finite Element Solvers  

E-Print Network (OSTI)

de Janeiro, RJ 21945­970, Brazil Abstract A comparison is made of two iterative algorithms on the energy variation of the incremental correction through the iterative process, which seems to be a more of choice. The increasing computing power reached with vector and parallel computers has renewed

Coutinho, Alvaro L. G. A.

491

Least-squares finite elements and constrained evolution systems  

E-Print Network (OSTI)

in?nitesimal) generator of T is the linear operator A : D(and Generators Let X be a Banach space with norm X , A : D(A) ? X ? X be a lineara linear operator. Then, A is the in?nitesimal generator of

Szypowski, Ryan

2008-01-01T23:59:59.000Z

492

Computational wind engineering using finite element package ADINA  

E-Print Network (OSTI)

Design of tall and long span structures is governed by the wind forces. Inadequate research in the field of wind dynamics has forced engineers to rely on design codes or wind tunnel tests for sufficient data. The present ...

Bajoria, Ankur

2008-01-01T23:59:59.000Z

493

The Extended Finite Element Method for High Gradient Solutions  

E-Print Network (OSTI)

Outline Enrichment functions for high gradient solutions Motivation High gradient inside the domain (Shocks) High gradient at the boundary (boundary layers) Optimal set of enrichment functions Numerical for high gradient solutions Outline Enrichment functions for high gradient solutions Motivation High

494

Coupling of finite element and boundary integral methods for ...  

E-Print Network (OSTI)

Oct 8, 2009 ... sparse, and banded matrix; ½A12? is an Nn ? Ne rectangular and sparse ... ple MATLAB mesh generator distmesh2d by Persson and Strang [38] is ... 2 shows the graphs of the real part and the imaginary part of the field.

"Peijun Li"

2009-11-09T23:59:59.000Z

495

FINITE ELEMENT ANALYSIS OF STEEL WELDED COVERPLATE INCLUDING COMPOSITE DOUBLERS  

E-Print Network (OSTI)

With the increasing focus on welded bridge members resulting in crack initiation and propagation, there is a large demand for creative solutions. One of these solutions includes the application of composite doublers over the critical weld. In order...

Petri, Brad

2008-05-15T23:59:59.000Z

496

electroseismic monitoring of co2 sequestration: a finite element ...  

E-Print Network (OSTI)

The injection of large amounts of man-produced CO2 in depleted oil wells below ..... [7] SANTOS, J. E., Global and domain-decomposed mixed methods for the ...

Fabio Zyserman

497

Finite element based inversion for time-harmonic electromagnetic problems  

Science Journals Connector (OSTI)

......water scenario. In shallow water the air wave dominates the...recovered as well as in our deep water study which can be seen as...A Quality Tetrahedral Mesh Generator and 3D Delaunay Triangulator...Department of Earth, Ocean and Atmospheric Sciences Vancouver, BC Canada......

Christoph Schwarzbach; Eldad Haber

2013-01-01T23:59:59.000Z

498

Computable Error Bounds in the Finite-Element Method  

Science Journals Connector (OSTI)

......carefully estimating the integrals is applied by Arcangeli & Gout (1976) and Gout (1977); they used the Taylor series remainder and...D. Thesis. Univ. of Zurich. ARCANGELI, R., & GOUT J. L. 1976 Sur revaluation de l'erreur d'interpolation......

REINHARD LEHMANN

1986-07-01T23:59:59.000Z

499

Finite Element Methods for Nonlinear Acoustics in Fluids  

E-Print Network (OSTI)

could include both material and geometric nonlinearities. However ..... easily be made explicit by an appropriate selection of parameters, see.6. Figures 7, 8, and

500

A finite element method for surface diffusion: the parametric case  

E-Print Network (OSTI)

, 3000 Santa Fe, Argentina (pmorin@math.unl.edu.ar). Partially supported by CONICET of Argentina and NSFS S is the Laplace-Beltrami operator and is the elastic energy density of the bulk (t) enclosed by (t

Nochetto, Ricardo H.