Inviscid Flow Field Analysis of Maneuvering Hypersonic Vehicles Using the SCM Formulation and Parabolic Grid Generation

摘要

The split-coefficient matrix (SCM) form of the Euler equations for a cylindrical base coordinate system is extended to allow the use of a generalized three-dimensional grid generation scheme. A grid generation scheme based on a parabolic partial differential equation is developed. Grids are obtained without iteration by marching from the body to the shock with body and shock points specified. The SCM type body boundary condition has been found to underpredict surface pressure for geometries with small radii of curvature. An improved method of characteristic (MOC) type body boundary condition has been developed which uses SCM type differencing in the crossflow direction. The improved MOC boundary condition has been found to have the robustness of the SCM type scheme while having superior accuracy. Solutions using the SCM form of the Euler equations with the parabolic grid generator and the improved MOC body boundary condition have been obtained for a hypersonic six fin missile. Generally good agreement is found in comparisons of the inviscid predictions with experimental data. (ERA citation 10:037319)