190320 Implementation of multi-level contact detection in granular LAMMPS
Channel: ARCHER UK National Supercomputing Service
Date: 2019-03-21

Tom Shire, University of Glasgow and Kevin Stratford, EPCC

Discrete element modelling (DEM) is a computational tool for predicting how granular materials will respond during loading, flowing or other processes found in nature or in industry. Each grain in a system is modelled as an individual element, and the elements interact to model to overall system response. The most time consuming parts of a DEM simulation are calculating which grains are in contact with each other and communicating this information between processors when running simulations in parallel. In most DEM codes these stages become prohibitively time consuming when a wide range of particles are employed, as the number of potential inter-particle contacts dramatically increases. This eCSE project has implemented an improved contact detection scheme for DEM simulations of materials with a wide range of particle sizes into LAMMPS, a widely used open-source software which is especially efficient for massively parallel simulations which can be run using supercomputers such as ARCHER. The new scheme limits the search range over which particle-contacts must be checked by defining different ranges depending on the size of particles - e.g. potential contacts between two large particles use a larger search area than between a small and large or two small particles. This webinar will introduce the basics of DEM and the new method to improve detection for polydisperse materials. Following this preliminary results and future plans will be discussed.