DEM study on the coupling effect between particle shape-size on the mixing performance in a double barrel with differential velocity

The effect of particle shape and size on the mixing performance of a double barrel with differential velocity (DBDV) was investigated on the basis of a discrete element method (DEM). The mixing performance was determined on the basis of the velocity, mixing efficiency and mixing uniformity. The DBDV model, motion model and particle models of different shapes were constructed. The motion process of the particles was visualized by a DEM. The effect of particle shape, particle size and their coupling effect on the mixing performance of DBDV was analyzed. The simulation results were validated. The results indicate that the differential zone is less sensitive to particle shape than the nondifferential zone. In terms of mixing uniformity, choosing a lower linear velocity at low and medium inclinations is more appropriate; similarly, choosing a high linear velocity at a large inclination is more appropriate. In the differential region, the particle velocity decreases as the particle size decreases. The mixing uniformity increases but then decreases with increasing particle curvature and decreasing particle size. The particle size significantly affects the mixing time and mixing uniformity of particles. Choosing medium-sized ellipsoidal and square particles is better for achieving high mixing uniformity.