A flux vector splitting scheme for low Mach number flows in preconditioning method.

The stiffness of Euler equations system increases, with the decreasing of Mach number, which results in poor convergence when solving steady flow problems numerically. In order to accelerate the convergence, a preconditioning method is proposed. A flux vector splitting scheme is derived from the classic Steger–Warming scheme and the Roe flux difference splitting scheme, and preconditioned systems developed for the two schemes, separately. Numerical results are presented and it is shown that flux vector splitting scheme can be preconditioned as successfully as flux difference splitting, and exhibits similar convergence acceleration and accurate solution.