The Experts below are selected from a list of 4305 Experts worldwide ranked by ideXlab platform
Victor Sofonea - One of the best experts on this subject based on the ideXlab platform.
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High-order thermal lattice Boltzmann models derived by means of Gauss quadrature in the Spherical Coordinate System.
Physical review. E Statistical nonlinear and soft matter physics, 2012Co-Authors: Victor E. Ambrus, Victor SofoneaAbstract:We use the Spherical Coordinate System in the momentum space and an appropriate discretization procedure to derive a hierarchy of lattice Boltzmann (LB) models with variable temperature. The separation of the integrals in the momentum space into angular and radial parts allows us to compute the moments of the equilibrium distribution function by means of Gauss-Legendre and Gauss-Laguerre quadratures, as well as to find the elements of the discrete momentum set for each LB model in the hierarchy. The capability of the high-order models in this hierarchy to capture specific effects in microfluidics is investigated through a computer simulation of Couette flow by using the Shakhov collision term to get the right value of the Prandtl number.
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Thermal Lattice Boltzmann models derived by Gauss quadrature using the Spherical Coordinate System
Journal of Physics: Conference Series, 2012Co-Authors: Victor E. Ambrus, Victor SofoneaAbstract:A hierarchy of thermal Lattice Boltzmann models is derived by separation of variables using the Spherical Coordinate System in the momentum space. The moments of the equilibrium distribution function are computed by means of Gauss-Legendre and Gauss-Laguerre quadratures. This procedure allows us to find the discrete momentum vectors for each model in the hierarchy. The Shakov collision term is used to get the right value of the Prandtl number. Computer simulation of Couette flow is used to illustrate the capability of these models to capture specific effects in microfluidics.
Victor E. Ambrus - One of the best experts on this subject based on the ideXlab platform.
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High-order thermal lattice Boltzmann models derived by means of Gauss quadrature in the Spherical Coordinate System.
Physical review. E Statistical nonlinear and soft matter physics, 2012Co-Authors: Victor E. Ambrus, Victor SofoneaAbstract:We use the Spherical Coordinate System in the momentum space and an appropriate discretization procedure to derive a hierarchy of lattice Boltzmann (LB) models with variable temperature. The separation of the integrals in the momentum space into angular and radial parts allows us to compute the moments of the equilibrium distribution function by means of Gauss-Legendre and Gauss-Laguerre quadratures, as well as to find the elements of the discrete momentum set for each LB model in the hierarchy. The capability of the high-order models in this hierarchy to capture specific effects in microfluidics is investigated through a computer simulation of Couette flow by using the Shakhov collision term to get the right value of the Prandtl number.
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Thermal Lattice Boltzmann models derived by Gauss quadrature using the Spherical Coordinate System
Journal of Physics: Conference Series, 2012Co-Authors: Victor E. Ambrus, Victor SofoneaAbstract:A hierarchy of thermal Lattice Boltzmann models is derived by separation of variables using the Spherical Coordinate System in the momentum space. The moments of the equilibrium distribution function are computed by means of Gauss-Legendre and Gauss-Laguerre quadratures. This procedure allows us to find the discrete momentum vectors for each model in the hierarchy. The Shakov collision term is used to get the right value of the Prandtl number. Computer simulation of Couette flow is used to illustrate the capability of these models to capture specific effects in microfluidics.
Chi-wang Shu - One of the best experts on this subject based on the ideXlab platform.
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A Direct Solver for 2D Non-Stationary Boltzmann-Poisson Systems for Semiconductor Devices: A MESFET Simulation by WENO-Boltzmann Schemes
Journal of Computational Electronics, 2003Co-Authors: José A. Carrillo, Irene M. Gamba, Armando Majorana, Chi-wang ShuAbstract:We present preliminary results of a high order WENO scheme applied to deterministic computations for two dimensional formulation of the transients for the Boltzmann-Poisson System describing electron transport in semiconductor devices. The collisional term models optical-phonon interactions which become dominant under strong energetic conditions corresponding to nanoscale active regions under applied bias. We treat the Boltzmann Transport equation in a Spherical Coordinate System for the wave-vector space. The problem is three dimensional in the wave-vector space and two dimensional in the physical space, plus the time variable driving to steady states. The new formulation avoids the singularity due to the Spherical Coordinate System.
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A WENO-Solver for the 1D Non-Stationary Boltzmann–Poisson System for Semiconductor Devices
Journal of Computational Electronics, 2002Co-Authors: José A. Carrillo, Irene M. Gamba, Armando Majorana, Chi-wang ShuAbstract:In this work we present preliminary results of a high order WENO scheme applied to a new formulation of the Boltzmann equation (BTE) describing electron transport in semiconductor devices with a Spherical Coordinate System for the phase velocity space. The problem is two dimensional in the phase velocity space and one dimensional in the physical space, plus the time variable driving to steady states. The new formulation avoids the singularity due to the Spherical Coordinate System.
Ching-chih Chen - One of the best experts on this subject based on the ideXlab platform.
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numerical solution for the hyperbolic heat conduction problems in the radial Spherical Coordinate System using a hybrid green s function method
International Journal of Thermal Sciences, 2010Co-Authors: Tzer-ming Chen, Ching-chih ChenAbstract:Abstract The hyperbolic heat conduction problems in the radial–Spherical Coordinate System are investigated by the hybrid Green's function method. The present method combines the Laplace transform for the time domain, Green's function for the space domain and ɛ -algorithm acceleration method for fast convergence of the series solution. Three different examples problems have been analyzed by the present method. It is found that the present method does not exhibit numerical oscillations at the wave front and the numerical solutions are stable.
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Numerical solution for the hyperbolic heat conduction problems in the radial–Spherical Coordinate System using a hybrid Green's function method
International Journal of Thermal Sciences, 2010Co-Authors: Tzer-ming Chen, Ching-chih ChenAbstract:Abstract The hyperbolic heat conduction problems in the radial–Spherical Coordinate System are investigated by the hybrid Green's function method. The present method combines the Laplace transform for the time domain, Green's function for the space domain and ɛ -algorithm acceleration method for fast convergence of the series solution. Three different examples problems have been analyzed by the present method. It is found that the present method does not exhibit numerical oscillations at the wave front and the numerical solutions are stable.
José A. Carrillo - One of the best experts on this subject based on the ideXlab platform.
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A Direct Solver for 2D Non-Stationary Boltzmann-Poisson Systems for Semiconductor Devices: A MESFET Simulation by WENO-Boltzmann Schemes
Journal of Computational Electronics, 2003Co-Authors: José A. Carrillo, Irene M. Gamba, Armando Majorana, Chi-wang ShuAbstract:We present preliminary results of a high order WENO scheme applied to deterministic computations for two dimensional formulation of the transients for the Boltzmann-Poisson System describing electron transport in semiconductor devices. The collisional term models optical-phonon interactions which become dominant under strong energetic conditions corresponding to nanoscale active regions under applied bias. We treat the Boltzmann Transport equation in a Spherical Coordinate System for the wave-vector space. The problem is three dimensional in the wave-vector space and two dimensional in the physical space, plus the time variable driving to steady states. The new formulation avoids the singularity due to the Spherical Coordinate System.
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A WENO-Solver for the 1D Non-Stationary Boltzmann–Poisson System for Semiconductor Devices
Journal of Computational Electronics, 2002Co-Authors: José A. Carrillo, Irene M. Gamba, Armando Majorana, Chi-wang ShuAbstract:In this work we present preliminary results of a high order WENO scheme applied to a new formulation of the Boltzmann equation (BTE) describing electron transport in semiconductor devices with a Spherical Coordinate System for the phase velocity space. The problem is two dimensional in the phase velocity space and one dimensional in the physical space, plus the time variable driving to steady states. The new formulation avoids the singularity due to the Spherical Coordinate System.