Development of a navier-stokes flow solver for all speeds on unstructured grids

A finite volume, cell-centered, density-based flow solver on unstructured grids is developed. The Weiss & Smith precondition matrix is implemented for solving incompressible and compressible flows at all speeds. The AUSMDV (Advection Upstream Splitting Method) scheme with a second order reconstruction is given for the explicit Runge-Kutta and implicit Lower-Upper Symmetric Gauss-Seidel (LU-SGS) time integration methods. Numerical simulation of inviscid flows through a channel with a bump at various Mach numbers and driven flows in a square cavity are presented to demonstrate the performance of the solver. General solution enhancement and convergence acceleration for steady-state Navier-Stokes solutions are attained via the use of inviscid or viscous preconditioning. At last, the analysis of the internal flow in a model solid rocket motor and JPL nozzle are made by the use of this solver. The ability of the solver in providing accurate steady-state solutions for transonic and low-speed flow of variable density fluids is demonstrated.