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Related papers: BGK model for rarefied gas in a bounded domain

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In the paper, assuming that the motion of rarefied gases in a bounded domain is governed by the angular cutoff Boltzmann equation with diffuse reflection boundary, we study the effects of both soft intermolecular interaction and…

Analysis of PDEs · Mathematics 2019-09-04 Renjun Duan , Feimin Huang , Yong Wang , Zhu Zhang

This minicourse contains a description of recent results on the modelling of rarefied gases in weakly non equilibrium regimes, and the numerical methods used to approximate the resulting equations. Therefore this work focuses on BGK type…

Computational Physics · Physics 2019-02-25 Gabriella Puppo

The collision consistency between the BGK collision model equation and lattice-BGK (LBGK) model is proposed by researching the physical significance of the relaxation factor tau in LBGK model. For microscalar flow in which the continuum…

Materials Science · Physics 2007-05-23 Chun Zou , Zhi-Wei Tian , Hong-Juan Liu , Chu-Guang Zheng

The Fourier-transformed version of the BGK model in one-dimension is solved in order to determine the general solution's asymptotics. The ultimate goal of this paper is to demonstrate that the solution to the model Boltzmann possesses a…

Analysis of PDEs · Mathematics 2017-04-26 Thomas E Carty

The BGK model kinetic equation is applied to spatially inhomogeneous states near steady uniform shear flow. The shear rate of the reference steady state can be large so the states considered include those very far from equilibrium. The…

Statistical Mechanics · Physics 2009-10-30 Mirim Lee , James W. Dufty

In this paper, we provide a result of exponential stability for several dissipative linear kinetic equations with heavy-tailed equilibria. The approach, inspired by the so-called $L^2$-hypocoercivity method, is robust enough to provide…

Analysis of PDEs · Mathematics 2025-12-24 Maxime Herda , Marc Pegon , Isabelle Tristani

A novel hybrid algorithm is presented for the Boltzmann-BGK equation, in which a low-rank decomposition is applied solely in the velocity subspace, while a full-rank representation is maintained in the physical (position) space. This…

Numerical Analysis · Mathematics 2025-08-25 Andres Galindo-Olarte , Joseph Nakao , Mirjeta Pasha , Jing-Mei Qiu , William Taitano

In this paper we study the effect of randomness on a linearized BGK-model in one dimension. We prove exponential decay rate to a global equilibrium. This decay rate can be proven to be independent of the stochastic influence in a physical…

Analysis of PDEs · Mathematics 2023-10-09 Tobias Herzing , Christian Klingenberg , Marlies Pirner

Wave disturbances of a stratified gas are studied. The description is built on a basis of the Bhatnagar -- Gross -- Krook (BGK) kinetic equation which is reduced down the level of fluid mechanics. The double momenta set is introduced inside…

Fluid Dynamics · Physics 2009-11-11 Dmitry Vereshchagin , Sergey Leble

In this paper, we study a time discrete scheme for the initial value problem of the ES-BGK kinetic equation. Numerically solving these equations are challenging due to the nonlinear stiff collision (source) terms induced by small mean free…

Numerical Analysis · Mathematics 2010-04-01 Francis Filbet , Shi Jin

Let $\Omega\subset\BBR^N$ be a bounded $C^2$ domain and $\CL_\gk=-\Gd-\frac{\gk}{d^2}$ the Hardy operator where $d=\dist (.,\prt\Gw)$ and $0<\gk\leq\frac{1}{4}$. Let $\ga_{\pm}=1\pm\sqrt{1-4\gk}$ be the two Hardy exponents, $\gl_\gk$ the…

Analysis of PDEs · Mathematics 2014-10-07 Konstantinos Gkikas , Laurent Veron

An unstable one-dimensional Bernstein-Greene-Kruskal (BGK) mode has been studied through high-precision numerical simulations. The initial turbulent, periodic equilibrium state is obtained by solving a Vlasov-Poisson system for initially…

Plasma Physics · Physics 2025-12-15 Sofia Zanelli , Gabriele Celebre , Sergio Servidio , Francesco Valentini

A simple iterative approach for solving a set of implicit kinetic moment equations is proposed. This implicit solve is a key component in the IMEX discretization of the multi-species Bhatnagar-Gross-Krook (M-BGK) model with nontrivial…

Numerical Analysis · Mathematics 2024-04-30 Evan Habbershaw , Cory D. Hauck , Steven M. Wise

We obtain the existence, uniqueness and regularity results for solutions to kinetic Fokker-Planck equations with bounded measurable coefficients in the presence of boundary conditions, including the inflow, diffuse reflection and specular…

Analysis of PDEs · Mathematics 2025-02-25 Yuzhe Zhu

We study an initial-boundary value problem for the incompressible Navier-Stokes-Cahn-Hilliard system with non-constant density proposed by Abels, Garcke and Gr\"{u}n in 2012. This model arises in the diffuse interface theory for binary…

Analysis of PDEs · Mathematics 2023-02-21 Helmut Abels , Harald Garcke , Andrea Giorgini

Ideal gases can be modeled by the Boltzmann equation from statistical physics. Instead of trying to track the position and velocity of a large number of gas molecules, it is possible to describe the particles with a particle distribution…

Numerical Analysis · Mathematics 2025-11-27 Vienna B. Rossmanith

We propose an extension of the Ellipsoidal-Statistical BGK model to account for discrete levels of vibrational energy in a rarefied polyatomic gas. This model satisfies an H-theorem and contains parameters that allow to fit almost arbitrary…

Statistical Mechanics · Physics 2020-07-07 Y Dauvois , J. Mathiaud , Luc Mieussens

We introduce in this work an efficient numerical method for the simulation of the quantum Liouville-BGK equation, which models the diffusive transport of quantum particles. The corner stone to the model is the BGK collision operator,…

Numerical Analysis · Mathematics 2021-03-12 Sophia Potoczak Bragdon , Olivier Pinaud

The ellipsoidal BGK model is a generalized version of the original BGK model designed to reproduce the physical Prandtl number in the Navier-Stokes limit. In this paper, we propose a new implicit semi-Lagrangian scheme for the ellipsoidal…

Analysis of PDEs · Mathematics 2018-07-30 Giovanni Russo , Seok-Bae Yun

We prove convergence of a variational formulation of the BDF2 method applied to the non-linear Fokker-Planck equation. Our approach is inspired by the JKO-method and exploits the differential structure of the underlying $L^2$-Wasserstein…

Numerical Analysis · Mathematics 2018-01-30 Simon Plazotta