Simulation of deformation and breakup of large aggregates in flows of viscous fluids

摘要

A three-dimensional modified discrete element method (mDEM) in which the effecti,e particle surface for the hydrodynamic drag force and the disturbance of neighboring particles on the flow field are taken into account is proposed to simulate the deformation and breakup process of large aggregates in flows. First, the dynamic shape factor of rectangular aggregates is simulated and compared with the corresponding experiment. sho:jng that the method can predict 'the behavior of aggregates in fluids quantitatively, Secondly the method is applied to simulate the breakup of large pariicle-cluster and cluster-cluster aggregates in shear and elongational flows. It is found that a power law relation holds between the average number of particles in broken fragments