Issue link: https://resources.randsim.com/i/1481018
2 W H I T E P A P E R Bulk materials have one-of-a-kind shapes, aspect ratios, and material properties that are modeled in Rocky as fibers, shells, and solid particles--otherwise known as granular materials. Depending on the type of particle, distinct breakage approaches can be applied to mimic the breakage behavior of these materials, based on different energy threshold criteria. Instant fragmentation models are useful in the comminution industry, where the fragments' particle size distribution is important. On the other hand, discrete breakage is useful when the breakage mechanism and the crack propagation are being studied. 2 INSTANTANEOUS FRAGMENTATION Traditional approaches in Rocky DEM simulations for comminution processes consider particles as a single entity until the actual breakage event. These approaches can use the Ab-T10 or the Tavares model. Breakage phenomenon occurs when a certain threshold is reached, based on the selected model and on the parameters provided by the user to represent the actual material. The particle is instantaneously replaced by fragments, which are simulated as separate DEM particles and can be later re-broken. These methods require two sets of functions: a threshold for particle breakage, which determines if a particle is going to be broken under a certain applied energy; and the size distribution of the fragments being generated in the breakage process. Properly calibrated, these models allow Rocky DEM to accurately predict product size distribution, throughput, forces, and power draw for the comminution devices in a reasonable amount of simulation time. Both instant fragmentation models are commonly used to accurately represent the breakage phenomenon and simulate mining equipment, such as mills, shredders, cone crushers, jaw crushers, hammer mills, and high-pressure grinding rolls. Figure 1 shows an ore shredder simulation, highlighting how a proper particle breakage model is needed to ensure the prediction of particle flow through the equipment. Figure 1: Simulation of an ore shredder in which brittle material is broken.