A generic energy‐conserving discrete element modeling strategy for concave particles represented by surface triangular meshes

Abstract

AbstractA generic energy‐conserving linear normal contact model for concave particles in the discrete element method (DEM) is presented in this article. It is derived based on a recently enhanced general energy‐conserving contact theory for arbitrarily shaped particles. A set of more effective evaluation schemes required in the model are also given, which shows that only the intersection boundary between two contact shapes, instead of their contact region or surfaces, is required to be explicitly obtained, thereby substantially improving both efficiency and applicability of the proposed contact model over the previous version. A surface triangular mesh is used to represent any 3D concave particle. The computational issues associated with the contact of two surface triangulated 3D shapes, including the contact detection, the determination of intersection boundary segments, the computation of contact features and parallelization, critical time step, and friction and damping treatment for multiple contacts are described in detail. Two sets of numerical examples involving various concave 3D shapes with a large number of surface triangles are presented to demonstrate either the superb energy‐conserving property of the proposed model model, or its effectiveness, robustness, and universal nature for wider and more complex problems.