Numerical solution of three-dimensional heterogeneous solid propellants

Abstract

We have described, for the first time, a fully coupled low Mach number numerical algorithm which can be used to investigate the combustion of composite propellants. The code uses a body fitted grid along the moving interface by means of a mapping technique. Specifically, the surface is assumed to be single valued, thus allowing the use of a mapping function that effectively maps the propagating corrugated surface into a stationary flat surface. The transformed connection conditions are then applied along the stationary flat surface, allowing second-order one-sided derivatives to be used. This has proven to be a very robust and efficient way to treat the surface and the connection conditions. Numerical tests are performed and the scheme is shown to be second-order accurate in the spatial directions as well as in time. Selected results are presented for heterogeneous propellants.