Coordinated Time-Stepping Method for Coupled DEM–FEM–MBD Algorithm

Abstract

The coordination of time steps directly affects the accuracy and efficiency of the calculation results in the simulation of the interaction between particles and structures. In this paper, a coordinated time-stepping method for coupling is proposed. The discrete element method (DEM) is used to establish the particle model, and the finite element method (FEM) and multibody dynamics (FEM-MBD) are applied to establish the structural model. The time step of the coupling algorithm between particles and a structure is discussed. The calculation efficiency and accuracy of the above methods are verified by an impact model, particle free falling model and electric pendulum model. Finally, the factors affecting the calculation efficiency of the coupling algorithm are discussed. The results show the following: compared with the theoretical solution, the calculation results of the coordinated time-stepping method are accurate. The multiple relationships of time steps between DEM and FEM-MBD are defined as communication coefficients, and the selection of a communication coefficient of 10 or 50 can effectively improve the calculation efficiency. When the communication coefficient continues to increase, the improvement of the calculation efficiency is not obvious. The number of structural elements has a great impact on the calculation efficiency, the number of particles in a certain range has a small impact on the calculation efficiency, and the time step of the DEM has a great influence on the calculation efficiency. The coordination time step method can improve the efficiency of the calculation while ensuring the accuracy of the calculation.