An Investigation of the Falling Phenomenon of Granular Materials from a Vessel

Abstract

Flow rate of granular materials discharged from a bin through a chute are influenced in many cases by the properties of material themselves and the forms of the chute. In this study the effects of the properties of materials, the dimensions of the opening of the bin outlet, and the inclined angle and the wall roughness of the rectangular open channel attached as a chute to the side of the rectangular bin on the flow rate of granular materials are investigated. Glass beads and sand are used as granular materials.In conclusion, the flow rate of granular materials from a bin through a chute of open channel becomes lower than that for no chute. It increases as the inclined angle of the open channel increases. When the particles flow through the entire section of the opening at the bin outlet, its rate is expressed by the experimental equation considering the wall roughness of the open channel. Further, when there is some deposit of the particles at the bin outlet and the entire section is not used as the outlet for the particles, the flow rate is expressed by the experimental equation with the effective opening of the bin outlet. From these two equations, we can calculate minimum inclined angle of the open channel which have a suitable capacity of flow rate and no deposit of the particles near the bin outlet.