Discrete element simulation of liquid-particle flows

A deterministic model for predicting the flow of suspensions of particles in viscous liquids is presented. The discrete element method (DEM) is used for evaluating the motion of the suspended particles by accounting the forces acting on them. Particle–particle and particle–wall colloidal, hydrodynamic and soft-sphere collision forces and Stokes-like drag from the suspending medium are considered. The flow of the suspending medium, assumed unaffected by the presence of the particles, is evaluated by a Finite Element Method. The model is applied to flow of a suspension of sub-micro-sized particles inside a three-dimensional geometry that resembles the exit of a slot coater. Because of the large number of particles involved, parallelization of the algorithm is necessary. The preliminary results indicate the effect of the accounted forces on the agglomeration process. The parallelization speed-up is excellent.