The granular flow in a particle moving bed with a side exit at the bottom was simulated by using a three-equation discrete element method(DEM) model that considers rolling friction.It was demonstrated that the computational granular dynamics (CGD) method can accurately predict the flow behavior of the particles in the complex granular systems
including the time averaged velocity field and the velocity fluctuations.The granular flow had certain similarities to fluid flow
such as the random fluctuation of velocities.However
the physical mechanism for the intermittent behavior in the granular flow was different from fluid flow.The granular flow showed great discontinuity.The friction coefficients of particles
which greatly affected the dynamics in the granular flow were discussed in the numerical simulations.