An unstructured grid generation and adaptive solution technique for high Reynolds number compressible flows.

Abstract

A method for simulating two-dimensional, high-Reynolds-number, compressible flows about complex geometries is described. The solution methodology consists of three main components: a general unstructured mesh-generation procedure, an implicit solution algorithm, and a solution-adaptive remeshing procedure. The unstructured mesh-generation procedure is designed to resolve efficiently the wide range of geometric and physical length scales present in these types of flows. In the thin boundary layers and wakes, a node-marching procedure is used to generate highly stretched, near right-triangular elements. In the predominantly inviscid regions, an advancing-front method is used to generate high-quality, near-equilateral elements. An implicit, higher-order, upwind method is also presented for solving the Reynolds-averaged Navier-Stokes equations with a one-equation turbulence model on these meshes. A solution-adaptive remeshing procedure that allows the mesh to adapt itself to flow features is also described. A procedure for tracking wakes and refinement criteria appropriate for shock wave detection are given. Results are shown for several complex external and internal flows which clearly demonstrate the utility of the method.