Whitepapers

1 W H I T E P A P E R The accurate prediction of particle size reduction through breakage is probably the most challenging problem for the Discrete Element Method (DEM). Such simulations not only involve capturing the fracture mechanisms accurately but also dealing with increased computational costs due to smaller particle fragments and larger particle counts. However, despite the increased computational cost, which can be handled efficiently using multi GPU hardware, accurate breakage models are needed to represent industrial comminution processes, such as jaw crushers, cone crushers, high-pressure grinding rolls (HPGR), and so on. This article describes the methods and models available in Rocky DEM that can predict particle breakage for different types of particle shapes: fibers, shells, and solids. The challenges, benefits, and limitations of these methods are also elucidated. 1 INTRODUCTION The discrete element method (DEM), first proposed by Cundall and Strack [1], is a simulation approach that allows reproducing the motion and interaction of multiple particles virtually. For each particle, trajectories are computed through Newton's second law of motion and contact models in the normal and tangential directions [2]. This technique is used to solve problems that deal with granular materials, and it can be useful for simulations in the comminution industry, where several processes involve breaking a larger particle into several smaller fragments [3]. Depending on the application, particle breakage can be desired, or not. Although DEM simulations were almost exclusively conducted with non-breakable particles until a certain point in history, recent hardware improvements have allowed engineers to run breakage models with ease, helping many industries with their project decisions. Better product efficiency, improved quality control, and even cost reduction are possible outcomes from these analyses due to the high confidence level that can be obtained from simulations. The unique breakage capabilities of Rocky allow simulations of any particle shape with high fidelity to experimental results. These simulations, combined with outstanding computational performance from current hardware, provide results in viable timeframes. Particle breakage models for predicting comminution process in Rocky DEM Guilherme Hanauer de Lima, M.Sc. 1 , Leon White Nogueira, M.Sc. 1 , Rahul Bharadwaj, Ph.D. 1 1 ESSS Rocky DEM

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