Modelling discrete fragmentation of brittle particles

A novel discrete fragmentation method (DFM) for spherical brittle particles using the discrete element method (DEM) has been developed, implemented and validated. Trajectories of individual fragments can be studied from the moment of breakage where the progeny might originate from incremental, simultaneous and/or repetitive fragmentation events. A particle breaks depending on the applied dynamic impact forces from collisions, the damage history, the particle size and material properties. This 3D model requires setting parameters solely dependent on the particle material and is consequently independent of any empirical value. Mass, momentum and energy is conserved during breakage. A theoretically consistent description from the onset of fragmentation to the cloud formation after breakage is provided and model outcomes have been compared to experimental results and other model predictions where very little deviation has been encountered. All material parameters have been varied independently to study the sensitivity of the model under dynamic fragmentation of numerous particles in a semi-autogenous mill.

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