有限要素法による衝撃波捕獲解析

The shock capturing analysis by using FEM (Finite Element Method) is described. The artificial viscosity is necessary for stable calculation to capture the shock wave, but it decreases the accuracy of solution. In this paper, the artificial viscosity is discussed from the viewpoint of SUPG (Streamline Upwind Petrov-Galerkin) method and tensor viscosity. The strain invariant is used in order to judge the region to operate the artificial viscosity. Flowfield around the sphere and cylinder under several Mach numbers are calculated, and good correlation between numerical and experimental results are obtained. The transonic flow can be also simulated by this FEM.