Discrete element modeling of non-spherical particles using a spherical shape

Abstract

Real non-spherical particles can be modeled using the Discrete Element Method (DEM) with sphere clusters, superquadrics, or polyhedral particles. However, in applications involving a considerable number of particles, the analysis can become impracticable. The goal of this study is to demonstrate how well spherical particles can reproduce the flow of differently shaped particles. In this analysis, four dry particles are employed with different shapes and sphericity: spherical particles and three nonspherical particles, constituted by a combination of three spherical particles. For each non-spherical particle ensemble, the respective angles of repose were determined with DEM simulations using a simple virtual flow box experiment. Next, the flow of spherical particles through the flow box was calibrated to reach the same angle of repose for each non-spherical particle ensemble by tuning friction coefficients. A comparison of the computational time of the simulations for each non-spherical particle and their spherical representation is presented and discussed. The results show that using spherical particles in DEM simulations reduces the computational processing time in relation to the use of irregular forms in the simulations by approximately 80%.