动态负载平衡的二维非结构网格DSMC并行算法研究

基于PC-CLUSTER群机并行体系结构与消息传递库MPI并行环境,研究了二维非结构网格DSMC并行算法。提出一类非结构网格动态分区策略,保证各子区域的分子数量大致相等,实现计算进程间的动态负载平衡。利用MPI库函数构造了符合DSMC并行原理的单步通讯法。采用单控制多数据流(SPMD)以及Master/Slave并行模式,设计了二维非结构网格DSMC整体并行算法。在程序的编制过程中,充分展现了Fortran90高级语言的主要特性,引人动态数组、指针、链表及派生类型数据。最后对过渡流域高超声速绕流进行了并行计算,数值试验的结果表明本文设计的并行算法可以取得较为理想的加速比。

A parallel algorithm of 2D unstructured DSMC method with dynamic load balance

This paper is to study parallel algorithm of 2D unstructured DSMC method on PC-CLUSTERS that is distributed memory architecture using the MPI standard library.In order to obtain high parallel efficiency,a new adaptive domain decomposition technique is presented.Because this method results in equal number of molecules among processors,dynamic load balance is maintained.Single step communication methods are constructed by means of MPI library.A complete parallel algorithm of 2D unstructured DSMC method is designed using SPMD and master/slave parallel mode.New feature of FORTRAN90 is fully exploited which makes the code more flexible.Finally,numerical experiments are made for hypersonic rarefied gas flow past cylinder.In some extent,the numerical results confirm the feasibility of method mentioned above.