465 IGPM465.pdf        May 2017
TITLE Efficient high-order discontinuous Galerkin computations of low Mach number flows
AUTHORS Jonas Zeifang, Klaus Kaiser, Andrea Beck, Jochen Schütz, Claus-Dieter Munz
ABSTRACT In this work, we consider the efficient approximation of low-Mach flows by a high-order scheme. This scheme is a coupling of a discontinuous Galerkin (DG) discretization in space and an implicit/explicit (IMEX) discretization in time. The splitting into linear implicit and nonlinear explicit parts relies heavily on the incompressible solution. The method has been originally developed for a singularly perturbed ODE and applied to the isentropic Euler equations. Here, we improve, extend and investigate the so called RS-IMEX splitting method. The resulting scheme can cope with a broader range of Mach numbers without running into roundoff errors, it is extended to realistic physical boundary conditions and it is shown to be highly efficient in comparison to more standard solution techniques.
KEYWORDS discontinuous Galerkin, IMEX-Runge-Kutta, low Mach number, splitting, asymptotic preserving