A Study on the Method to Reduce Penetration Behavior in Non-smooth DEM

Abstract

Non-smooth DEM (N-DEM) is a particle method used to analyze systems with various particle behaviors. It is a method that uses the contact law, and it is possible to analyze with a larger step width than the conventional DEM. However, it has been confirmed that penetrating behavior occurs in the analysis result by N-DEM when the step width is too large. N-DEM does not generate a force that reduces the penetration amount, which affects the analysis accuracy. Therefore, the purpose of this research is to reduce penetrating behavior by introducing the DEM concept, consepuently to analyze the particle behavior more accurately. Since DEM calculates the repulsive force from the overlap amount and the overlap rate, it is possible to reduce the penetration. In addition, the proposed method, which combines N-DEM and DEM, can realize more accurate behavior of particles in a shorter analysis time. In this paper, the results of the proposed method are shown for the penetration caused by the collision of two particles. DEM is only applied in the normal direction when the normal penetration is large in the collision of two particles. And the energy was evaluated for the analysis result by the proposed method.