The Mechanism of Transportation inside the Screw Conveyer

A screw conveyer is extensively used as transport equipment for granular materials. Until now, there have been several reports investigating the characteristics of the screw conveyer, the influence of the rotational speed of the screw shaft, the size and the shape of a screw blade and a filling ratio of granules on the transport efficiency of the screw conveyer. However, a study of the transport mechanism of granules has rarely been reported. The mechanism of transportation inside the screw conveyer is very complicated. Therefore, it is difficult to understand the dynamic behavior of granules quantitatively. In this paper, in order to grasp the transporting state inside the screw conveyer from phenomenal aspects, it is expressed using two parameters i. e. the transport quantity and the leakage quantity in the stationary state. At first, the relation between the transport quantity and the leakage quantity is examined by measuring them practically. Next, on the basis of the relation, the transient transporting state of granules is investigated by computer simulation. Finally, the mechanism of transportation inside the screw conveyer becomes clear through the simulation.