A novel non-overlapping approach to accurately represent 2D arbitrary particles for DEM modelling

Abstract

Mechanical behaviors of granular materials are complicated and greatly influenced by the particle shape. Current, some composite approaches have been proposed for realistic particle shape modelling within discrete element method (DEM), while they cannot give a good representation to the shape and mass properties of a real particle. In this work, a novel algorithm is developed to model an arbitrary particle using a cluster of non-overlapping disks. The algorithm mainly consists of two components: boundary filling and domain filling. In the boundary filling, some disks are placed along the boundary for a precise representation of the particle shape, and some more disks are placed in the domain to give an approximation to the mass properties of the particle in the domain filling. Besides, a simple method is proposed to correct the mass properties of a cluster after domain filling and reduce the number of the disks in a cluster for lower computational load. Moreover, it is another great merit of the algorithm that a cluster generated by the algorithm can be used to simulate the particle breakage because of no overlaps between the disks in a cluster. Finally, several examples are used to show the robust performance of the algorithm. A current FORTRAN version of the algorithm is available by contacting the author.

Keywords

discrete element method (DEM) / composite approaches / arbitrary particles / clusters / non-overlapping disks

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