3D hybrid mesh generation for complex geometry

A novel hybrid mesh generation algorithm for the three-dimensional viscous flow computations is proposed firstly. The initial surface mesh is generated by the advancing front triangulator. Then the boundary layer is configured with the anisotropic prismatic elements by an advancing layer mesher. For the robustness enhancement and the improvement of the boundary layer elements quality, a series of procedures are adopted at the following several aspects: the computation and smoothing of the marching directions, adaptive adjustment the marching step size, multi-marching directions, and correct the invalid grid elements. In addition, an auto-receding method allows the generation of non-overlapping prismatic mesh even in complex geometries that contain narrow gaps and cavities. Then the mesh generation process is finalized with the far field filled with the isotropic tetrahedral elements generated by the Delaunay-type mesher and the updating of surface mesh on the symmetry plane. Finally, mesh examples and simulation results for several models are presented to demonstrate the efficiency and effectiveness of the proposed algorithm.