Generation of non-isotropic unstructured grids via directional enrichment

A procedure for the generation of highly stretched grids suitable for Reynolds-averaged Navier{Stokes (RANS) calculations is presented. In a rst stage, an isotropic (Euler) mesh is generated. In a second stage, this grid is successively enriched with points in order to achieve highly stretched elements. The element reconnection is carried out using a constrained Delaunay approach. Points are introduced from the regions of lowest stretching towards the regions of highest stretching. The procedure has the advantages of not requiring any type of surface recovery, not requiring extra passes or work to mesh concave ridges=corners, and guarantees a nal mesh, an essential requirement for industrial environments. Given that point placement and element quality are highly dependent for the Delaunay procedure, special procedures were developed in order to obtain optimal point placement