Monte Carlo particle simulation of low-density fluid flow on MIMD supercomputers

Direct simulation Monte Carlo is a well-established technique for modeling low density fluid flows. The parallel implementation of a general simulation which allows for body-fitted grids, particle weighting, and a variety of surface and flow chemistry models is described. The authors compare its performance on a 1024-node nCUBE 2 to a serial version for the CRAY-YMP. Experiences with load-balancing the computation via graph-based heuristics and the newer spectral techniques are also discussed. This is a critical issue, since density fluctuations can create orders-of-magnitude differences in computational loads as the simulation progresses