Discrete Element Modelling on a Cluster of Workstations

We describe a distributed computing system for discrete element modelling that has been designed for loosely-coupled networks of workstations. The implementation is based on DM

2 , a state-of-the-art discrete element modelling technique for simulating the behaviour of energetic materials and modelling shock compaction phenomena. The underlying computational approach is derived from particle methods, where short-range interactions, both mechanical and thermochemical, determine individual particle movement and state. Using spatial decomposition, a client-server software architecture distributes the computations and, at the language level, Berkeley sockets enable communication between conventional Unix processes on workstations connected by an Ethernet. We evaluate the performance of the system in terms of overall execution time and efficiency, and develop a simple model of computational and communication costs that enables us to predict its performance in other contexts. We conclude that distributed implementations of short-range particle methods can be very effective, even on non-dedicated communication networks.