Parallel volume meshing using face removals and hierarchical repartitioning

Abstract

Parallel unstructured three-dimensional mesh generation is a challenging problem for many reasons, the most obvious coming from the complexity of ‘partitioning’ the problem such that meshing is load balanced at all times. In this paper, a parallel volume meshing procedure whose input is a surface mesh (distributed or not) is presented. In order to help drive the parallel execution, a distributed octree is built considering the surface mesh and meshing size attributes. The tree is partitioned in parallel using the Recursive Bisection methodology and ‘portions of space’ are handed out to processors for meshing. Volume meshing operates on two techniques: (i) octant template meshing for interior octants; and (ii) face removals (advancing front) to fill the space in between the surface mesh and the ‘templated’ octants. Due to the mesh being distributed, domains corresponding to the interfaces of the initial partitioning are left unmeshed. To complete volume meshing, it is necessary to repartition the interface domains. A hierarchical repartitioning procedure has been developed to effectively mesh face, edge, and vertex interfaces. It is the focus of this paper.