高性能非结构化四面体网格解耦并行生成算法

Hi-performance Decoupled Parallel Mesh Generation Algorithm for Unstructured Tetrahedral Mesh

针对大规模科学计算领域非结构化网格生成问题,提出一种基于AFT-Delaunay方法的三维复杂域解耦并行四面体网格生成算法.该算法以待剖分三维域的闭合的表面三角形网格为输入,采用边界一致约束Delaunay剖分方法串行地生成较小规模的初始四面体网格;采用界面优先策略扩展三维AFT-Delaunay方法,以几何分界面为参考指引前沿推进方向,在分界面处生成一层由四面体单元构成的有厚度的"墙",递归、并行地将初始四面体网格分割成完全解耦的子区域;此时,各子区域均为不含内部节点的四面体网格,继续利用AFT-Delaunay方法解耦并行地生成各子区域内部四面体网格.算例结果表明,文中算法很好地解决了分界面处网格质量差的难题以及收敛性问题,具有较好的并行效率及几何适应性,可在PC平台全自动地完成108量级的非结构四面体网格生成.

To meet the needs of the large scale scientific computations,a strongly decoupled parallel3D mesh generation algorithm based on the AFT-Delaunay method is presented.For a given surface mesh bounding an arbitrary3D region for meshing,a constrained Delaunay Triangulation method is employed to generate the initial tetrahedral mesh with few elements by a single thread.And then,an extended AFT-Delaunay method which can advance the front along a specific path is proposed to decompose the initial tetrahedral mesh region into sub-domains recursively and independently by introduction of a bisection plane.At last,each sub-domain is refined with the AFT-Delaunay method by a single thread in a decoupled manner.Experiments on several complex3D models have been conducted,and hundreds millions of unstructured tetrahedral elements are generated automatically on the PC platform.This algorithm can guarantee the mesh quality of both the boundary of whole region and the interface between sub-domains,meanwhile,effectiveness and robustness are achieved.