Hexahedral meshing of non-linear volumes using Voronoi faces and edges

摘要

This work extends an algorithm presented in our recent paper (Sheffer et al. Engng. Comput. 1999; 15: 248-262.) for automatic hexahedral meshing, based on the embedded Voronoi graph (EVG). The embedded Voronoi graph contains the full symbolic information of the Voronoi diagram and the medial axis of the objet, and a geometric approximation to the real geometry. The EVG is used for decomposing the object, into simple sub-volumes meshable by basic meshing techniques. The EVG provides complete information regarding proximity and adjacency relationships between the entities of the volume. Hence, decomposition faces are determined unambiguously, without any further geometric computations and the resulting sub-volumes are guaranteed to be well defined and disjoint. The decomposition algorithm is applicable to any volume, including volumes with degenerate medial axis. The previous paper defined the decomposition based on sub-volumes sweepable perpendicular to an EVG face. This work extends the decomposition to handle all types of EVG entities, providing a complete decomposition of the volume. It analyses the types of sub-volumes that are generated and the meshing techniques applicable to them.