Convergence toward the steady state of a collisionless gas with Cercignani–Lampis boundary condition

Mar 1, 2022·
Armand Bernou
Armand Bernou
· 1 min read
Abstract
We study the asymptotic behavior of the kinetic free-transport equation enclosed in a regular domain, on which no symmetry assumption is made, with Cercignani–Lampis boundary condition. We give the first proof of existence of a steady state in the case where the temperature at the wall varies, and derive the optimal rate of convergence toward it, in the L1 norm. The strategy is an application of a deterministic version of Harris’ subgeometric theorem, in the spirit of the recent results of Cañizo-Mischler and of the previous study of Bernou. We also investigate rigorously the velocity flow of a model mixing pure diffuse and Cercignani–Lampis boundary conditions with variable temperature, for which we derive an explicit form for the steady state, providing new insights on the role of the Cercignani–Lampis boundary condition in this problem.
Type
Publication
Communications in Partial Differential Equations, vol. 47, 4

This article is the starting point of my project focusing on the Cercignani-Lampis boundary condition in kinetic theory. You might also want to check the related preprint Asymptotic Behavior of Degenerate Linear Kinetic Equations with Non-Isothermal Boundary Conditions, where I consider collisional models with the same boundary conditions.