Size Segregation in Granular Beds Subject to Discrete and Continuous Vertical Oscillations

Abstract

ABSTRACTSize segregation of particulates is of concern in a number of industries that handle materials such as chemicals, pharmaceuticals, fertilizers, and food products. Of particular interest in this paper is segregation resulting from externally applied vibration. In industrial applications this vibration may either be applied intentionally in devices such as vibrating conveyors or “live wall” hoppers, or unintentionally during material handling and transport. This paper investigates size segregation in granular beds subject to discrete “taps” and continuous, sinusoidal vertical vibration. The results from discrete element computer simulations indicate that the rise rate of a single impurity increases monotonically with amplitude for discrete vibrations but for continuous vibrations the rise rate increases, reaches a maximum value, then decreases as the oscillation amplitude increases.