Unstructured Fixed Grid with Moving Body, Navier-Stokes Computational Fluid Dynamic (CFD) Solver for Simulating Gas Flows

UNSTRUCTURED FIXED GRID WITH MOVING BODY, NAVIER-STOKES COMPUTATIONAL FLUID DYNAMIC (CFD) SOLVER FOR SIMULATING GAS FLOWS Technical Abstract In this project, a parallel computational fluid dynamics tool/design is proposed to solve problems involving moving body components. Unstructured fixed-grids are used to model solid body geometry and flow domain. Different from traditional overset Chimera grid method, proposed method will be based on filling overlap regions with the same type of unstructured grids used for the flow solution. This will reduce effort spent for communicating information between the blocks that overlap, knowing that interpolation is one of the issues in traditional overset grid approaches. Traditional Chimera methods will also be evaluated for comparison purposes. Ultimate goal of the design is to transient flow simulation of the Divert and Attitude Control Systems (DACS) for kinetic warheads for MDA Sea Based Midcourse ballistic missile defense. Flow solver uses implicit time integration and upwind flux differencing for better accuracy in time dependent problems such as the flow simulation of DACS in kill warheads. Parallel implementation is based on Message Passing Interface libraries, and Solver will be portable across several operating systems.