Numerical Comparison of Contact Force Models in the Discrete Element Method

The discrete element method (DEM) is usually applied in analyzing the scientifical origin/evolution of asteroids and landing/sampling regolith. In order to manage contact between non-spherical granules, Polygonal Contact Model (PCM) has been introduced into DEM method. This paper applies four different force models newly-proposed algorithm analyze their difference implication. include one linear model three nonlinear derived from complete Mindlin–Deresiewicz equations. By considering macroscopical results calculation efficiency, single-collision multiple-collision cases are analyzed by comparing models. Specifically, restitution coefficient, angular velocity, rebound angle, kinetic energy as indicators for single collision. case studied under Brazil nut effect with ellipsoidal granules. Additionally, softening feasibility also discussed decreasing Young’s modulus material, mainly outgoing efficiency.