Parallel Load Balancing Heuristics for Radiative Heat Transfer Calculations

The computation of radiative effects by the Photon Monte Carlo method is computationally demanding, especially when complex, nongray absorption models are employed. To solve such computationally expensive problems we have developed a parallel software framework for the photon Monte Carlo method based on ray tracing to compute radiative heat transfer effects. The central problem with obtaining scalable performance for this method is that widely varying physical properties over the computational domain result in highly skewed processor work assignment. In this paper we present computational results that demonstrate the effectiveness of a geometry based, domain partitioning heuristic with element weights for solving this load balancing problem. We present computational results that compare this heuristic to competing schemes for a representative combustion problem.