Numerical simulation of three-dimensional inviscid internal flows using unfactored upwind-relaxation sweeping algorithm

摘要

The linear stability analysis of the unfactored upwind relaxation-sweeping (URS) algorithm for 3D flow field calculations has been carried out and it is shown that the URS algorithm is unconditionally stable. The algorithm is independent of the global sweeping direction selection. However, choosing the direction with relatively low variable gradient as the global sweeping directions results in a higher degree of stability. Three-dimensional compressible Euler equations are solved by using the implicit URS algorithm to study internal flows of a nonaxisymmetric nozzle with a circular-to-rectangular transition duct and complex shock wave structures for a 3D channel flow. The efficiency and robustness of the URS algorithm has been demonstrated.