DEM modelling of particulate flow in a screw feeder

Feeders are an important class of particulate handling equipment and are used to facilitate the controlled removal of bulk materials from hoppers and bins. In this paper we examine the flow of particulates in a screw feeder. This consists of a long inclined screw with constant pitch and spacing drawing down from a V shaped slot hopper and transporting along an inclined tube or trough. The detailed flow patterns in the feeder and the resulting draw down patterns in the hoppers are predicted using the Discrete Element Method (DEM). Comparison of predictions using spherical and non-spherical particle shapes demonstrate the importance of particle shape. The draw down patterns show a strong and realistic pre-disposition to remove material from the rear of the feeders. This preferential draw down pattern leads to gross circulation in the bins, non-uniform residence times and segregation effects.