Collision Detection and Administration Methods for Many Particles with Dierent Sizes

This paper deals with the calculation of the motion and the administration of the contacts for systems with many colliding bodies of round shape and possibly large size-dierences. Both two dimensional (2D) and three dimensional (3D) cases are investigated, while the eciency of the employed algorithms is compared. For the integration of the equations of motion, standard methods from Molecular Dynam-ics (MD) and Discrete Element Methods (DEM) are used and, to reduce the eort that is typically used for collision detection, some sophisticated administration al-gorithms for the neighborhood search are implemented. Especially for large systems with many particles with a wide, polydisperse size distribution, this is a challenge. In the following three methods, the Verlet-Neighbor List (VL), the Linked Cell (LC) method, and the Linked Linear List (LLL), are discussed and compared for 2D and 3D. Only LLL performs well for strongly dierent particle sizes. Key words: contact detection; neighborhood search; molecular dynamics (MD); discrete element method (DEM); polydisperse size-distriution Email addresses