The macroscopic bulk behaviour of powders is governed by the microscopic activity of the individual particles in an assembly. This implies that in order to gain a better understanding of particulate systems and their functioning, the particle interactions at the microscopic level must be analysed. It is currently very difficult to investigate the behaviour of individual particles within a bulk assembly experimentally. Therefore it is helpful to model the behaviour of particles by the use of numerical simulations. Furthermore the use of computer simulations provides a cost effective method as an alternative to experiments, since no physical material or process equipment is required, provided the simulation results are validated. Simulations are also invaluable for cases for which actual experiments are hazardous. For particulate solids, the most appropriate approach for this purpose is the use of computer simulation by the Distinct Element Method (DEM).
Within our research group we have access to a number of DEM codes including:
As a team with extensive expertise in the field of mathematical modelling we have provided further improvements in the commercial and open-source codes by incorporating customised functionalities, e.g. new contact models, zonal analysis, and stress and tribo-charging calculations.
We have recently developed a new simple contact model for DEM simulations of elasto-plastic and adhesive particles. This research provides enhancements in ability of DEM in capturing realistic powder behaviour for a wide range of particle properties. In another programme, the capabilities of DEM in predicting the dynamics of particulate flow inside an industrial mixer were demonstrated.