Determining the Motion Character of Loose Materials in the System of Continuous Action «Hopper – Reciprocating Plate Feeder»

Abstract

This paper reports methods for modeling the movement of bulk material in dispensing equipment of continuous action. It was established that modeling the pulsations and fractures in the flow of bulk material can be performed using the discrete element method. On its basis, a model has been constructed of the system consisting of a cylindrically-conically-shaped hopper and a reciprocating plate feeder of continuous action. Particles of bulk material are represented in the form of spheres with a constant radius between which the forces of friction and elasticity act.The result of modeling is the determined movement speed and position of each particle in the transverse section of the system «hopper‒ reciprocating plate feeder» and at the surface of a feeder's plate. The regions have been defined with typical movement speeds of bulk material, as well as the system's performance. The maximum speed of the particles is observed in the region of the outlet branch pipe of the hopper, along its central axis, and in the outer layer of the material that is found at the surface of a plate. Minimum speeds are observed near the walls of the hopper and at the center of a plate. It was established that in the course of a feeder's operation there is an increase in the radius of the cone of bulk material that resides at the surface of a plate, by 15.2 %.The system was experimentally studied using a testing bench, consisting of a conical-cylindrical hopper, a reciprocating plate feeder of continuous operation, and a data acquisition system. The feeder's performance under a steady operation mode has been determined. It was established that it is pulsating in character that matches the results from analytical calculations based on the constructed model. The conclusion about correspondence of the obtained results has been drawn based on the equality of variances in performance, which was checked using a Fisher criterion.The resulting model could be applied in order to analyze steady operational modes of reciprocating plate feeders of continuous action for the case when bulk material arrives to the center of a plat