Accuracy and stability analysis of the Semi-Lagrangian method for stiff hyperbolic relaxation systems and kinetic BGK model

TL;DR

This paper introduces third order asymptotic-preserving and asymptotically accurate semi-Lagrangian methods for stiff hyperbolic relaxation systems and kinetic BGK models, ensuring stability and accuracy in the fluid limit.

Contribution

The paper develops new third order DIRK schemes with proven AP and AA properties for stiff kinetic equations in the semi-Lagrangian framework.

Findings

The schemes achieve third order accuracy in the fluid limit.

Linear stability analysis confirms the schemes' stability.

Numerical tests demonstrate the schemes' effectiveness and stability.

Abstract

In this paper, we develop a family of third order asymptotic-preserving (AP) and asymptotically accurate (AA) diagonally implicit Runge-Kutta (DIRK) time discretization methods for the stiff hyperbolic relaxation systems and kinetic Bhatnagar-Gross-Krook (BGK) model in the semi-Lagrangian (SL) setting. The methods are constructed based on an accuracy analysis of the SL scheme for stiff hyperbolic relaxation systems and kinetic BGK model in the limiting fluid regime when the Knudsen number approaches $0$. An extra order condition for the asymptotic third order accuracy in the limiting regime is derived. Linear Von Neumann stability analysis of the proposed third order DIRK methods are performed to a simplified two-velocity linear kinetic model. Extensive numerical tests are presented to demonstrate the AA, AP and stability properties of our proposed schemes.