English
Related papers

Related papers: Hypocoercivity for a BGK model for gas mixtures

200 papers

We study a two phase flow with interactions of liquid and rarefied gas inside the gas phase. The gas phase is modeled by the BGK model of the Boltzmann equation. The liquid phase is modeled by the incompressible Navier-Stokes equations. In…

Fluid Dynamics · Physics 2022-04-06 S. Tiwari , A. Klar , G. Russo

In this paper, we establish hypocoercivity for the semiconductor Boltzmann equation with the presence of an external electrical potential under the Maxwell boundary condition. We will construct a modified entropy Lyapunov functional, which…

Analysis of PDEs · Mathematics 2025-09-03 Hongxu Chen , Liu Liu , Jiayu Wan

We analyse a continuum model for genetic circuits based on a partial integro-differential equation initially proposed in Friedman, Cai \& Xie (2006) as an approximation of a chemical master equation. We use entropy methods to show…

Analysis of PDEs · Mathematics 2019-04-12 José A. Cañizo , José A. Carrillo , Manuel Pájaro

In this paper we are interested in the large time behavior of linear kinetic equations with heavy-tailed local equilibria. Our main contribution concerns the kinetic L\'evy-Fokker-Planck equation, for which we adapt hypocoercivity…

Analysis of PDEs · Mathematics 2020-03-17 Nathalie Ayi , Maxime Herda , Hélène Hivert , Isabelle Tristani

The non-equilibrium gas dynamics is described by the Boltzmann equation, which can be solved numerically through the deterministic and stochastic methods. Due to the complicated collision term of the Boltzmann equation, many kinetic…

Computational Physics · Physics 2021-02-03 Xiaocong Xu , Yipei Chen , Kun Xu

In this paper we calculate the entropy production of a relativistic binary mixture of inert dilute gases using kinetic theory. For this purpose we use the covariant form of Boltzmann's equation which, when suitably transformed, yields a…

Statistical Mechanics · Physics 2015-09-10 Valdemar Moratto , A. L. Garcia-Perciante , L. S. Garcia-Colin

This paper investigates the diffusion limit of a kinetic BGK-type equation, focusing on its relaxation to a nonlinear aggregation-diffusion equation, where the diffusion exhibits a porous-medium-type nonlinearity. Unlike previous studies by…

Analysis of PDEs · Mathematics 2025-04-09 Young-Pil Choi , Jeongho Kim , Oliver Tse

In this work we prove sufficient conditions for the Glauber dynamics corresponding to a sequence of (non-product) measures on finite product spaces to be rapidly mixing, i.e. that the mixing time with respect to the total variation distance…

Probability · Mathematics 2019-02-27 Arthur Sinulis

We introduce in this paper a new approach to the problem of the convergence to equilibrium for kinetic equations. The idea of the approach is to prove a 'weak' coercive estimate, which implies exponential or polynomial convergence rate. Our…

Analysis of PDEs · Mathematics 2012-08-07 Minh-Binh Tran

High temperature gases, for instance in hypersonic reentry flows, show complex phenomena like excitation of rotational and vibrational energy modes, and even chemical reactions. For flows in the continuous regime, simulation codes use…

Computational Physics · Physics 2020-03-17 Céline Baranger , Yann Dauvois , Gentien Marois , Jordane Mathé , Julien Mathiaud , Luc Mieussens

Kinetic models of polyatomic gas typically account for the internal degrees of freedom at the level of the two-particle distribution function. However, close to the hydrodynamic limit, the internal (rotational) degrees of freedom tend to be…

Fluid Dynamics · Physics 2023-05-24 Praveen Kumar Kolluru , Mohammad Atif , Santosh Ansumali

In the present work, we extend the Discontinuous Galerkin Spectral Element Method (DGSEM) to high-enthalpy reacting gas flows with internal degrees of freedom. An entropy- and kinetic energy-preserving flux function is proposed which allows…

Fluid Dynamics · Physics 2024-11-21 Georgii Oblapenko , Arseniy Tarnovskiy , Moritz Ertl , Manuel Torrilhon

We establish convergence in the diffusive limit from entropy weak solutions of the equations of compressible gas dynamics with friction to the porous media equation away from vacuum. The result is based on a Lyapunov type of functional…

Analysis of PDEs · Mathematics 2021-03-22 Corrado Lattanzio , Athanasios E. Tzavaras

An adjoint-based shape optimization method for solid bodies subjected to both rarefied and continuum gas flows is proposed. The gas-kinetic BGK equation with the diffuse-reflection boundary condition is used to describe the multiscale gas…

Computational Physics · Physics 2025-01-03 Ruifeng Yuan , Lei Wu

A simplified relativistic kinetic theory for gases with internal degrees of freedom, based on a BGK-type collision term, is considered. First the Boltzmann equation is rewritten in tetrad form and then thermal coefficients are determined to…

General Relativity and Quantum Cosmology · Physics 2026-04-13 Philip Semrén , Michael Bradley , João M. S. Oliveira , M. Piedade Machado Ramos

Recently, a novel relativistic polyatomic BGK model was suggested by Pennisi and Ruggeri [J. of Phys. Conf. Series, 1035, (2018)] to overcome drawbacks of the Anderson-Witting model and Marle model.In this paper, we prove the unique…

Analysis of PDEs · Mathematics 2021-02-02 Byung-Hoon Hwang , Tommaso Ruggeri , Seok-Bae Yun

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 develop a generalized hyperdynamics method, which is able to simulate slow dynamics in atomistic general (both energy and entropy-dominated) systems. We show that a few functionals of the pair correlation function, involving two-body…

Statistical Mechanics · Physics 2009-11-11 Xin Zhou , Yi Jiang , Kurt Kremer , Hans Ziock , Steen Rasmussen

A new coercivity estimate on the spectral gap of the linearized Boltzmann collision operator for multiple species is proved. The assumptions on the collision kernels include hard and Maxwellian potentials under Grad's angular cut-off…

Analysis of PDEs · Mathematics 2015-11-13 Esther Sarah Daus , Ansgar Jüngel , Clément Mouhot , Nicola Zamponi

Theoretical description and simulation of large quantum coherent systems out of equilibrium remains a daunting task. Here we are developing a new approach to it based on the Pechukas-Yukawa formalism, which is especially convenient in case…

Statistical Mechanics · Physics 2017-05-31 Mumnuna A. Qureshi , Johnny Zhong , Joseph J. Betouras , Alexandre M. Zagoskin