Hierarchical template-based hexahedral mesh generation

Abstract

This work describes a hexahedral mesh generation algorithm ideally suited for transition subdomain meshes in the context of any domain decomposition meshing strategy. The algorithm is based on an automatic hierarchical region decomposition in which, in the last level, it is possible to generate hexahedral elements with a conventional mapping strategy. Templates usually impose restrictions on meshes on boundary surfaces of a subdomain to be meshed. The proposed hierarchical template scheme eliminates many of these restrictions, creating more options in surface meshes and mesh refinement as input boundary data. This work implements four basic templates for volumes that should be simplified by a unit box. The volume decomposition is performance using a cube-shaped parametric space in the local coordinate system. The algorithm decomposes hierarchically a volume until all volumes should be mappable to generate elements by the 3D mapping approach. Examples demonstrate that this idea may result in structured meshes in complex geometries.