Abstract: A parallel computing strategy for a 3D dynamic unstructured overset grids Navier-Stokes solver is developed in this article. The Navier-Stokes equations are discretized by a cell-vertex finite volume method in space and matched implicitly in time using a dual stepping method. The Spalart-Allmaras one-equation turbulence model is implemented to evaluate the turbulent viscosity. Parallel computation is based on the dynamic domain decomposition method which is performed using METIS system at each physical time step. Load balance is achievedby partitioning each component mesh according to the number of CPUs and weighing between active nodes and inactive nodes. Finally the parallel code is applied to inviscid flow simulation of store separation and viscous flow simulation of internal weapon bay opening to validate its accuracy, high parallel performance and the ability to deal with complex geometries.

Key words: unstructured overset grids, parallel computation, domain decomposition, Navier-Stokes equations, finite volume method