A novel coupled fluid–particle DEM for simulating dense granular slurry dynamics

We study two-dimensional flow of a granular slurry in a lid driven cavity using novel coupled fluid–particle discrete element simulations. The particles are assumed to be linearly elastic and fully immersed in a Newtonian fluid. In contrast to previous approaches to coupling fluid particle interactions, the fluid–particle interaction in the present study is modeled purely through Stokes’ drag. This assumption is based on the fluid inertia being small in comparison to particle inertia. Using this model, we study mixing of two initially stratified layers of the granular material in a belt-driven square cavity. We also study the microscopic aspects of the mixing process by monitoring the breakup of representative unit cells. Higher belt velocities are observed to require lower overall energy to achieve a well-mixed state.