Cartesian cut-cell method for axisymmetric separating body flows

A method for the calculation of unsteady, axisymmetric compressible flows i nvolving both fixed and separating bodies is presented. The method uses a C artesian cut-cell mesh approach and high resolution upwind finite volume sc heme. A stationary background Cartesian mesh is generated on the computatio nal domain with complex solid geometries represented by different types of cut cell. Solid bodies are allowed to move across the mesh using a finite v olume scheme modified to deal with moving boundary problems. The flow solve r employed is a MUSCL-Hancock Godunov-type scheme in conjunction with an ap proximate Riemann solver of the Harten, Lax, and van Leer type (for flow in terfaces) and an exact Riemann solver for a moving piston (for fixed or mov ing solid faces). A cell merging technique is used to maintain numerical st ability in the presence of arbitrarily small cut cells and to retain strict conservation at moving boundaries. The method is applied to a muzzle blast flow and muzzle break problems involving both fixed and separating bodies.