Speaker: Prof. Tao Xiong (熊涛教授)

Time: 15:00-16:00, 10 December 2021 (Friday) (Beijing time)

Venue: 华信书院, CC126

Abstract

In this work, we proposed high order semi-implicit schemes for the all Mach full Euler equations of gas dynamics. Material waves are treated explicitly, while acoustic waves are treated implicitly, thus avoiding severe CFL restrictions for low Mach flows. High order accuracy in time is obtained by semi-implicit temporal integrator based on the IMEX Runge-Kutta (IMEX-RK) framework. High order in space is achieved by finite difference WENO schemes with characteristic-wise reconstructions adapted to the semi-implicit IMEX-RK time discretization. The schemes are proven to be asymptotic preserving and asymptotically accurate as the Mach number vanishes. Besides, they can well capture discontinuous solutions in the compressible regime, especially for two dimensional Riemann problems. Numerical tests in one and two space dimensions will illustrate the effectiveness of the proposed schemes.

About Prof. Xiong

熊涛，厦门大学数学科学学院教授，主要研究方向为计算流体力学和动理学方程的高精度数值模拟，和合作者一起发展了高精度保持的高阶保正和保界数值流通量限制器方法，多尺度动理学方程的高阶渐近保持间断Galerkin有限元方法等，部分工作发表在SIAM期刊，Journal of Computational Physics等杂志。