Investigation of particulate bed dynamics inside a rotating drum using discrete element method

The present article describes a numerical study conducted to investigate particle movement inside a rotating drum under different operating conditions. The discrete element method (DEM) was used in order to describe granular flow dynamics. The effects of the main operating conditions (i.e., rotating speed and fill level) on the dynamic angle of repose were studied. It was found that the dynamic angle of repose increased by increasing the rotating speed and fill level. The results showed that by increasing the rotation speed, fraction of particles in the active area increased. While, by increasing the fill level, fraction of particles in the active area decreased. Also, granular temperature of the solid bed was calculated in order to characterize the velocity fluctuation of particles in the rotating bed. It was found that the granular temperature increased by increasing the rotating speed. Furthermore, the effect of the friction coefficient on the dynamics of granular particles was investigated. When the particle-particle and particle-wall friction coefficients are increased, the dynamic angle of repose is slightly increased. Also, the results showed that granular temperature increased as the friction coefficient decreased.