A parallel unstructured implicit solver for hypersonic reacting flow simulation

The chapter focuses on two aspects of the solver, as well as the parallel performance of the hybrid implicit method. A new parallel implicit solver for the solution of the compressible Navier-Stokes equations with finite rate chemistry on unstructured finite volume meshes is presented in the chapter. The solver employs the data-parallel line relaxation (DPLR) method for implicit time integration along the lines of cells that are normal to the wall. A point-implicit method is used in the regions where surface-normal lines are not constructed. The new method combines the robustness and efficiency of the implicit DPLR method with the flexibility of using unstructured discretizations. The solver employs a low-dissipation pure-upwind numerical scheme based on the Steger-Warming split flux method, as well as a MUSCL-type scheme designed for unstructured discretizations. The DPLR method is superior to other parallel methods, such as matrix-based point-implicit methods designed for chemically reacting hypersonic flow simulations.