二维自适应非结构网格DSMC并行算法研究

A parallel DSMC method using 2D self-adaptive unstructured meshes

研究了二维自适应非结构网格DSMC并行算法实现的过程。首先提出了一类非结构网格自适应策略,有效降低了网格尺度对计算结果的影响,提高了流场的分辨率;然后基于PC-CLUSTER群机并行体系结构与消息传递库MPI并行环境,利用分区并行思想,设计了非结构网格DSMC并行算法,节约了计算时间。利用For-tran90的动态分配内存技术编制了通用计算程序;最后对过渡流域高超声绕流进行了数值模拟,计算结果初步验证了算法的可行性与有效性。

In this paper, a parallel DSMC method Using 2D unstructured adaptive meshes is developed for the efficient simulation of rarefied gas flows. Strategies to adjust cell size are presented through mesh adaptation for the improvement of solution accuracy. A complete parallel algorithm of 2D unstructured DSMC method, including domain decomposition technique and communication method, is designed using SPMD and master/slave parallel mode. As a consequence, not only is the computation time reduced, but also is the computation precision largely improved. New feature of FORTRAN90 is fully exploited which makes the code more flexible. Finally, numerical experiments are made for hypersonic rarefied gas flow, In some extent, the numerical results confirm the feasibility of the method mentioned above.