Abstract:

Based on the grid decompostion across processors,a new Sn parallel algorithm for particle transport on unstructured grids is presented. The algorithm implements parallel computation for different angle directions and energy groups,according to the orders of the computing queue. During the parallel computation,it is not necessary to compute the priorities and arrange the priority queues. Synthesizing the data dependence of all directions and all grids,and combining with the Blevel priority,a new priority ordering algorithm is presented. In order to overlap the computation and communication,the algorithm gives priority to computing the grids which need not receive the upstream grids’ messages. Using the Sn parallel algorithm and the priority ordering algorithm,we solve a two dimensional particle transport equations on a parallel computer.The performance results show the algorithms have good scalability. The parallel efficiency is 52% when the processor number is extended for 64 to 1024.

Key words: parallel algorithm;particle transport;priority ordering algorithm;Sn method