Research on motion and mixing of polydisperse particles in a circular eccentric drum

The discrete element method (DEM) was employed to simulate motion and mixing of polydisperse particles in a rotary drum. The effects of eccentricity on partition of particle system and its regional variation, change of large particle velocity and mixing degree of polydisperse particles were studied. Results showed that the rolling regime is divided three areas in the eccentric drum, particle system, the stagnant layer, the active layer and the vortex core. There is no actual vortex core, the shape and position of the moving vortex core are periodically changed with the rotation of the drum in the eccentric drum. In the center drum, the velocity of large particles in the stagnant layer is basically equal in different particle motion period. But in the eccentric drum, the two uniform velocity of the large particle in the two adjacent stagnant layer is unequal. The change of large particle velocity is more obvious with increasing eccentricity. The eccentricity has little effect on contact result of polydisperse particles. The variation of contact numbers of polydisperse particles is similar to that of the damping vibration curve in the mixing process. © 2017, Chemical Industry Press. All right reserved.