Towards Automatic Construction of 3D Shock-fitted Meshes based on Robust Shock Detection and Processing

In this paper, we present a workflow towards automatic construction of 3D shock-fitted (unstructured) meshes based on a robust shock detection and processing approach. We build upon our prior work that can efficiently detect and process shocks in 3D including those computed on relatively coarse unstructured meshes. We apply a robust set of steps to target problems with shock systems containing interactions between different shock components/segments. In particular, the following steps are involved in shock processing: i) de-fragmentation to fill-up holes or missing shock elements/cells, ii) sorting/labeling to determine contiguous set of shock elements/cells, iii) removal of noise or small sets, and iv) identification of each distinct shock segment/component. The resulting information is used to create shock-fitted 3D geometries, and thus, shock-fitted 3D meshes that are composed of highly anisotropic orthogonal/layered elements aligned with shocks. To demonstrate the performance and utility of the current procedure, three inviscid flow problems are considered: i) a 2D diamond airfoil case with external planar shocks, ii) a 2D wedge duct case with internal reflected shocks, and iii) a 3D blunt body case with a bow shock. More complex cases including viscous flows with boundary layers will be considered in the future.