Comparison of DEM Software with Polyhedral Particle Shapes

The discrete element method (DEM) is a numerical modeling approach used to simulate granular materials, such as soil. Early DEM software used circular or spherical particle shapes for computational efficiency. However, soil particles are not spherical, and particle shape has a significant impact on soil strength and stiffness. More modern DEM software uses polyhedral particle shapes to better represent soil behavior; however, contact detection of polyhedral particles is computationally expensive. This computational cost has limited the size and type of geotechnical engineering problems that can be solved with DEM. Many researchers have developed simulation acceleration algorithms to expand the size of problems DEM can solve; however, there have been no systematic comparisons of the computational speed of available polyhedral-shaped DEM platforms. This study compares the computational speed and memory usage of three DEM software platforms: BLOKS3D, LAMMPS, and YADE-DEM, using simple particle gravity deposition simulations. The simulations involve deposition of particles in a container under gravity and reporting the computational times and memory usage for each simulation. Where possible, the same material properties and simulation settings are used for each software. BLOKS3D performed simulations approximately two orders of magnitude faster than YADE-DEM and LAMMPS. The memory usage was on the same order of magnitude for all platforms; however, LAMMPS and YADE-DEM had more efficient memory scaling than BLOKS3D.