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Related papers: Relaxation time approximations in PAOFLOW 2.0

200 papers

New method to simulate heat transport in multiphase lattice Boltzmann (LB) method is proposed. The energy transport equation needs to be solved when phase boundaries are present. Internal energy is represented by an additional set of…

Fluid Dynamics · Physics 2018-08-29 Alexander Kupershtokh , Dmitry Medvedev , Igor Gribanov

This study aims to validate the lattice Boltzmann method and assess its ability to accurately describe the behavior of gaseous flows in packed beds. To that end, simulations of a model packed bed reactor, corresponding to an experimental…

In this paper, a two-dimensional (2D) multiple-relaxation-time (MRT) lattice Boltzmann (LB) model is developed for simulating convection heat transfer in porous media at the representative elementary volume scale. In the model, a MRT-LB…

Computational Physics · Physics 2013-12-02 Qing Liu , Ya-Ling He , Qing Li , Wen-Quan Tao

The present review article has attempted a compact formalism description of transport coefficient calculations for relativistic fluid, which is expected in heavy ion collision experiments. Here, we first address the macroscopic description…

Nuclear Theory · Physics 2024-04-03 Ashutosh Dwibedi , Nandita Padhan , Arghya Chatterjee , Sabyasachi Ghosh

In the present work we compute the enhancement in the long time transport coefficients due to correlated motion of fluid particles at high density. The fully wave vecor dependent extended mode coupling model is studied with the inclusion of…

Statistical Mechanics · Physics 2016-08-31 Sudha Srivastava , Shankar P. Das

We consider the tight-binding approximation for the description of energy bands of graphene, together with the standard Boltzmann's transport equation and constant relaxation time, an expression for the conductivity was obtained. We…

Mesoscale and Nanoscale Physics · Physics 2015-10-26 S. S. Abukari , S. Y. Mensah , R. Musah , N. G. Mensah , K. A. Dompreh

We derive equations for fluid dynamics from a non-extensive Boltzmann transport equation consistent with Tsallis' non-extensive entropy formula. We evaluate transport coefficients employing the relaxation time approximation and investigate…

Nuclear Theory · Physics 2015-05-30 T. S. Biro , E. Molnar

Assuming an effective quadratic Hamiltonian, we derive an approximate, linear stochastic equation of motion for the density-fluctuations in liquids, composed of overdamped Brownian particles. From this approach, time dependent two point…

Soft Condensed Matter · Physics 2017-04-26 Matthias Krüger , David S. Dean

In this paper, we propose a novel two-relaxation-time regularized lattice Boltzmann (TRT-RLB) model for simulating weakly compressible isothermal flows. A free relaxation parameter, $\tau_{s,2}$, is employed to relax the regularized…

Fluid Dynamics · Physics 2024-03-28 Yuan Yu , Zuojian Qin , Siwei Chen , Shi Shu , Hai-Zhuan Yuan

The departure of a granular gas in the instable region of parameters from the initial homogeneous cooling state is studied. Results from Molecular Dynamics and from Direct Monte Carlo simulation of the Boltzmann equation are compared. It is…

Statistical Mechanics · Physics 2009-11-10 J. Javier Brey , M. J. Ruiz-Montero

The present paper discusses the diffusion approximation of the linear Boltzmann equation in cases where the collision frequency is not uniformly large in the spatial domain. Our results apply for instance to the case of radiative transfer…

Analysis of PDEs · Mathematics 2015-03-23 Claude Bardos , Etienne Bernard , François Golse , Rémi Sentis

Pressure (density) and velocity boundary conditions inside a flow domain are studied for 2-D and 3-D lattice Boltzmann BGK models (LBGK) and new method to specify these conditions are proposed. These conditions are consistent with the…

comp-gas · Physics 2008-02-03 Qisu Zou , Xiaoyi He

We present a robust approach to incorporating models for the time-variable broadening of the pulse profile due to scattering in the ionized interstellar medium into profile-domain pulsar timing analysis. We use this approach to…

Instrumentation and Methods for Astrophysics · Physics 2017-04-12 L. Lentati , M. Kerr , S. Dai , R. M. Shannon , G. Hobbs , S. Oslowski

The transport properties of the perovskites KTaO$_3$ are calculated using first-principles methods. Our study is based on Boltzmann transport theory and the relaxation time approximation, where the scattering rate is calculated using an…

Materials Science · Physics 2016-01-26 Burak Himmetoglu , Anderson Janotti

The far-from-equilibrium dynamics of an ultracold, one-dimensional Bose gas is studied. The focus is set on the comparison between the solutions of fully dynamical evolution equations derived from the 2PI effective action and their…

Other Condensed Matter · Physics 2008-11-26 Alexander Branschädel , Thomas Gasenzer

This paper presents an a-posteriori goal-oriented error analysis for a numerical approximation of the steady Boltzmann equation based on a moment-system approximation in velocity dependence and a discontinuous Galerkin finite-element (DGFE)…

Numerical Analysis · Mathematics 2017-10-11 M. R. A. Abdelmalik , E. H. van Brummelen

We present a technique for an exact solution of the linearized Boltzmann equation for the electrical and thermal transport coefficients in metals in the low-temperature limit. This renders unnecessary an uncontrolled approximation that has…

Statistical Mechanics · Physics 2021-01-04 J. Amarel , D. Belitz , T. R. Kirkpatrick

The nonparametric estimation of the distribution of relaxation times approach is not as frequently used in the analysis of dispersed response of dielectric or conductive materials as are other immittance data analysis methods based on…

Materials Science · Physics 2009-11-11 Enis Tuncer , J. Ross Macdonald

Real data are constrained to finite sampling rates, which calls for a suitable mathematical description of the corrections to the finite-time estimations of the dynamic equations. Often in the literature, lower order discrete time…

Data Analysis, Statistics and Probability · Physics 2015-05-13 C. Anteneodo , R. Riera

We present a dynamical description of slow relaxation processes based on the extension of Onsager's fluctuation theory to systems in local quasi-equilibrium. A non-Markovian Fokker-Planck equation for the conditional probability density is…

Statistical Mechanics · Physics 2009-11-10 I. Santamaria-Holek , A. Perez-Madrid , J. M. Rubi