Large-scale Parallel Discrete Element Simulations of Granular Flow

We present large-scale parallel direct numerical simulations of granular flow using a novel, portable software program for Discrete Element Method (DEM) simulations. Since particle methods provide a unifying framework for both discrete and continuous systems, we base the program on the ppm library [1], which has already been demonstrated to provide transparent parallelization and state-of-theart parallel efficiency using particle methods for continuous systems. Adapting ppm to discrete systems, we report results from three-dimensional simulations of a sand avalanche down an inclined plane [2, 3]. All simulations use the particle interaction model by Silbert et al. [4], including Hertzian contact forces and elastic and viscoelastic deformations. We demonstrate the parallel performance and scalability of the new simulation program using up to 122 million particles on 192 processors, employing adaptive domain decomposition and load balancing techniques.