A laboratory investigation and discrete element modeling of rock flow in a chute

A series of physical rock flow experiments have been conducted in a chute in the laboratory to simulate the rock flow that occurs in the chamber of a cone crusher. Discrete element modeling (DEM) has been subsequently used to model the granular flow experiments. The DEM models were validated against the velocity profiles obtained from the laboratory experiments performed. To simulate the rock flow, pebbles of different sizes were used in the experiments and simulated using clumps of overlapping spheres in the simulations. It was found that the method of deposition of the pebbles into the chute is important to the DEM simulation of the flow of the non-spherical particles. The validated DEM models were used to investigate the relationship between the chute aggregate clearance times, the chute closed-size setting (CSS) and the bite angle. An analysis of both the experimental and DEM studies concluded that both an increase in the bite angle and a decrease in CSS resulted in an increase in the chute clearance times. Moreover, for a constant bite angle, there are two critical CSS values, which depend on the sizes of particles: one which allows pebbles to flow and the other which results in a minimum clearance time.

In order to study the flow of irregular material in the chamber of a cone crusher, rock flow in a chute has been studied both physically in the lab and numerically using DEM without considering rock breakage. The DEM model was successfully validated and it was found that sample deposition and CSS are important to velocity profiles and clearance times of rocks.Figure optionsDownload as PowerPoint slideHighlights
► A laboratory test of rock flow in a chute was successfully modeled using DEM.
► Particle deposition is important to the DEM simulation modeling particle flow.
► An increase in the bite angle resulted in an increase of chute clearance time.
► A decrease in CSS resulted in an increase of chute clearance time.