Design of agglomerates using Weibull distribution to simulate crushable particles in the discrete element method

Abstract

This paper focuses on the use of the agglomerate technique to simulate crushable particles in the Discrete Element Method. A novel approach is proposed to design a Weibullian agglomerate by mimicking flaws within the crushable particle. The particle is designed with a constant number of sub-spheres in contrast to the approach widely used in the literature. However, the adhesion bonds between sub-spheres within the particle are selected randomly from a normal distribution. The normal distribution is designed to generate negative adhesion values, which are replaced by zero adhesion to mimic flaws within the particle. It is shown that the particle designed in this fashion exhibits a tensile strength that follows the Weibull probability function. This includes the effect of particle size that is remarkably captured quantitatively. Finally, a simple method is proposed to derive the parameters of the adhesion normal distribution from the Weibull parameters determined experimentally on single particle diametral compression tests.

Keywords
Agglomerate; Discrete element method; Crushable sand; Particle tensile strength; Weibull distribution