A GPU-based DEM framework for simulation of polyhedral particulate system

The contact overlap algorithms and contact models of both polyhedron-polyhedron and polyhedron-boundary contact in discrete element method (DEM) has been proposed. The overlap volume between contacting polyhedrons is explicitly calculated based on geometric dualization theory. The polyhedron-boundary contact is transferred to the contact between polyhedron and triangles. An improved parallelizing by candidate contact pair algorithm is provided to accelerate the accurate contact overlap algorithms. Furthermore, a DEM framework based on graphics processing unit, named as CoSim-DEM, has been developed to realize the high-performance simulation. The algorithms are validated using hopper flow experiments with 3D printed particles, and DEM parameters are calibrated by the experimental tests. Two benchmarks are used as the case extension of the algorithms: one is the interaction between a retaining rigid wall and granular material for quasi-static analysis; the other is the conveying motion of granular material in a screw conveyor for dynamic analysis. Finally, the computational efficiency of the developed algorithms is analyzed. All results indicate that the developed CoSim-DEM can be better used in the simulation of granular materials with polyhedral particles.