非凸区域上SPH计算结果后处理方法研究

郑俊, 于开平, 张嘉钟, 魏英杰

哈尔滨工业大学航天学院



摘要:

系统考察了利用Delaunay三角化实现SPH(smoothed particle hydrodynamics)算法后处理的途径.针对非凸物质域上SPH粒子点集的最小凸包的Delaunay三角化,会得到一些并不属于物质域的空白单元,提出一种"单元称重"算法,通过SPH求和近似获得单元的加权质量,利用不属于物质域中的空白单元的加权质量比其节点的平均质量小很多的特点,将它们从单元集中过滤掉.将过滤后剩下的单元作为有限单元并结合SPH粒子上的计算数据,导入到通用后处理软件Tecplot中,可以实现SPH计算结果的可视化,从而为SPH算法的后处理提供了一种简洁实用的途径.算法的适用性在具有材料飞溅和粒子不均匀分布的算例中得到了验证.

关键词:  SPH  非凸区域  Delaunay三角化  后处理  单元称重法

DOI：10.11918/j.issn.0367-6234.2011.03.003

分类号:O302

基金项目:国家自然科学基金资助项目(10832007)



The post-processing method of SPH on non-convex configuration

ZHENG Jun, YU Kai-ping, ZHANG Jia-zhong, WEI Ying-jie

School of Astronautics,Harbin Institute of Technology,150001 Harbin,China

Abstract:

A post-processing method for SPH was presented based on Delaunay triangulation.However for non-convex domain occupied by SPH particles(nodes),Delaunay triangulation results in some empty elements which contains no mass.Thus an "element mass weighing" method should be proposed to identify and delete those empty elements from the element collection.The reasonability of the algorithm is that each empty element has a very much less SPH-weighted-approximation than the average quality of the particles on it.With the SPH data and the kept elements being exported into the universal post-processing software Tecplot,the values at any point in the computational domain could be obtained.The feasibility of the algorithm was tested in a series of numerical cases including a case with heterogeneous particle distribution and material splashing.

Key words:  SPH  non convex domain  Delaunay triangulation  post processing  element mass weighing method