Effect of Particle Size on Flow Mode and Flow Characteristics of Pulverized Coal

Abstract

This paper reports on an extensive experimental campaign aimed at studying on effect of particle size and flow mode on the flow characteristics of pulverized coal. A series of pulverized coal changing the mean particle size in the range 18–224 μm were used as the experimental materials and three flow modes including gravity-induced flow, downwards and upwards mechanically forced flow were investigated. The gravity-induced flow was characterized by discharging pulverized coal from the Perspex hopper gravitationally, while the mechanically forced flow was performed inside a cylindrical vessel where the blade rotated and moved downwards or upwards to displace the pulverized coal. Furthermore, the relationship between different flow modes was discussed and the force analysis was used to reveal the flow mechanisms of gravity-induced flow.