Dynamic Load Balancing Applied to a Parallel Direct Simulation Monte Carlo Implementation

The direct simulation Monte Carlo (DSMC) method is a versatile computational technique capable of simulating a wide range of gas ows. It can compute from the continuum to the rar-eeed regime. It is a molecular simulation method and consequently it can model complex thermo-chemical physics with relative ease. Unfortunately the method is computationally expensive in terms of memory and compute time. However the method is suitable for parallelisation in a multi-processor (MP) environment. An implementation of DSMC for MP environments using a domain decomposition technique and unstructured grids is presented. The domain decomposition technique leads to load balance problems across the processor array. This is alleviated by the implementation of an adap-tive domain decomposition technique, which is described and set in context against other mesh partitioners. The technique is illustrated with an example.