Mesh Generation and Adaption for High Reynolds Number RANS Computations

This proposal offers to provide NASA with an automatic mesh generator for the simulation of aerodynamic flows using Reynolds-Averages Navier-Stokes (RANS) models. The tools will be capable of generating high-quality, highly-stretched (anisotropic) grids in boundary layer regions and transition smoothly to inviscid flow regions even in an adaptive context. The objective of the work is to offer a unified view for generating quality and robust RANS meshes coupled naturally with anisotropic mesh adaptation. Our innovation is to view the anisotropic mesh generation within the Riemannian metric framework which thus far has been used exclusively in anisotropic mesh adaptation. Using the metric-based framework allows much easier handling of the large mesh size ratios involved in the computation, whereas traditional methods use the Euclidean framework to compute distance and volume. This innovative view to generate these meshes makes the entire procedure more generic and much more robust. The emphasis is being put on deriving a completely automatic process to generate quality and robust anisotropic meshes. Our existing and proven software package will be modified to include these innovative methods. A NASA test case will be computed for validation of the methods. The software will be delivered in Phase II.