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Related papers: Asymptotic-Preserving methods and multiscale model…

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This paper is devoted to the numerical approximation of a degenerate anisotropic elliptic problem. The numerical method is designed for arbitrary space-dependent anisotropy directions and does not require any specially adapted coordinate…

Numerical Analysis · Mathematics 2014-04-08 Stéphane Brull , Pierre Degond , Fabrice Deluzet

We propose a new class of asymptotic preserving schemes to solve kinetic equations with mono-kinetic singular limit. The main idea to deal with the singularity is to transform the equations by appropriate scalings in velocity. In…

Numerical Analysis · Mathematics 2017-06-30 Alina Chertock , Changhui Tan , Bokai Yan

We present a new asymptotic strategy for general micro-macro models which analyze complex viscoelastic fluids governed by coupled multiscale dynamics. In such models, the elastic stress appearing in the macroscopic continuum equation is…

Mathematical Physics · Physics 2025-12-22 Xuenan Li , Chun Liu , Di Qi

Goal of this paper is to investigate several numerical schemes for the resolution of two anisotropic Vlasov equations. These two toy-models arise from a kinetic description of a tokamak plasma confined by strong magnetic fields. The…

Numerical Analysis · Mathematics 2017-08-10 Baptiste Fedele , Claudia Negulescu

Astrophysical fluids under the influence of magnetic fields are often subjected to single-fluid or two-fluid approximations. In the case of weakly ionized plasmas however, this can be inappropriate due to distinct responses from the…

Astrophysics · Physics 2008-11-26 S. O'Sullivan , T. P. Downes

The present paper introduces an efficient and accurate numerical scheme for the solution of a highly anisotropic elliptic equation, the anisotropy direction being given by a variable vector field. This scheme is based on an asymptotic…

Numerical Analysis · Mathematics 2014-04-08 Pierre Degond , Fabrice Deluzet , Alexei Lozinski , Jacek Narski , Claudia Negulescu

The main purpose of the present paper is to study from a numerical analysis point of view some robust methods designed to cope with stiff (highly anisotropic) elliptic problems. The so-called asymptotic-preserving schemes studied in this…

Numerical Analysis · Mathematics 2015-07-06 Alexei Lozinski , Jacek Narski , Claudia Negulescu

We develop efficient asymptotic-preserving time discretization schemes to solve the disparate mass kinetic system of a binary gas or plasma in the "relaxation time scale" relevant to the epochal relaxation phenomenon. Since the resulting…

Numerical Analysis · Mathematics 2019-09-05 Irene M. Gamba , Shi Jin , Liu Liu

An asymptotic model based on a reductive perturbative expansion of the drift kinetic and the Maxwell equations is used to demonstrate that, near the instability threshold, the nonlinear dynamics of mirror modes in a magnetized plasma with…

Plasma Physics · Physics 2015-05-13 E. A. Kuznetsov , T. Passot , P. L. Sulem

In this article we introduce an asymptotic preserving scheme designed to compute the solution of a two dimensional elliptic equation presenting large anisotropies. We focus on an anisotropy aligned with one direction, the dominant part of…

Numerical Analysis · Mathematics 2014-04-08 Pierre Degond , Fabrice Deluzet , Claudia Negulescu

We develop a purely hydrodynamic formalism to describe collisional, anisotropic instabilities in a relativistic plasma, that are usually described with kinetic theory tools. Our main motivation is the fact that coarse-grained models of high…

High Energy Physics - Phenomenology · Physics 2017-01-04 Esteban Calzetta , Alejandra Kandus

Mathematical models and numerical simulations offer a non-invasive way to explore cardiovascular phenomena, providing access to quantities that cannot be measured directly. In this study, we start with a one-dimensional multiscale blood…

Machine Learning · Computer Science 2026-04-09 Giulia Bertaglia , Raffaella Fiamma Cabini

For static reductions of isotropic and anisotropic Magnetohydrodynamics plasma equilibrium models, a complete classification of admitted point symmetries and conservation laws up to first order is presented. It is shown that the symmetry…

Mathematical Physics · Physics 2009-11-13 Alexei F. Cheviakov , Stephen C. Anco

The purpose of this paper is to bridge kinetic plasma descriptions and low frequency single fluid models. More specifically, the asymptotics leading to Magneto-Hydro-Dynamic (MHD) regimes starting from the Vlasov-Maxwell system are…

Plasma Physics · Physics 2020-04-21 A. Crestetto , F. Deluzet , D. Doyen

In this paper, we derive a new shallow asymptotic model for the free boundary plasma-vacuum problem governed by the magnetohydrodynamic equation, vital in describing large-scale processes in flows of astrophysical plasma. More precisely, we…

Analysis of PDEs · Mathematics 2020-08-24 Diego Alonso-Orán

We investigate the dynamics of plasma-based acceleration processes with collisionless particle dynamics and non negligible thermal effects. We aim at assessing the applicability of fluid-like models, obtained by suitable closure assumptions…

We consider various sets of Vlasov-Fokker-Planck equations modeling the dynamics of charged particles in a plasma under the effect of a strong magnetic field. For each of them in a regime where the strength of the magnetic field is…

Analysis of PDEs · Mathematics 2020-06-30 Maxime Herda , Luis Miguel Rodrigues

We develop an asymptotic-preserving scheme to solve evolution problems containing stiff transport terms. This scheme is based to a micro-macro decomposition of the unknown, coupled with a stabilization procedure. The numerical method is…

Numerical Analysis · Mathematics 2018-02-21 Baptiste Fedele , Claudia Negulescu , Stefan Possanner

In high-temperature plasma physics, a strong magnetic field is usually used to confine charged particles. Therefore, for studying the classical mathematical models of the physical problems it needs to consider the effect of external…

Numerical Analysis · Mathematics 2025-09-05 Anjiao Gu , Yajuan Sun

A largely unsolved theoretical issue in controlled fusion research is the consistent \textit{kinetic} treatment of slowly-time varying plasma states occurring in collisionless and magnetized axisymmetric plasmas. The phenomenology may…

Plasma Physics · Physics 2015-05-30 Claudio Cremaschini , Massimo Tessarotto