Modelling of particle stratification in jigs by the discrete element method

Abstract

This paper attempts to review the theories and mathematical models which have been advanced to explain the jigging process. The existing literature on mathematical modelling and quantitative analysis of jigging reveal that very little is known about the stratification of particles in a jig bed. It is realized that a microscopic model is the one that is most suited to study stratification in jigs. A new modelling approach based on Newtonian mechanics is used to study the stratification behavior of particles in a batch jig. In this approach, the motion of solid particles is treated using the discrete element method (DEM). Since in DEM, the motion of the particles is computed from the forces acting on them, the effect of the fluid is easily incorporated through the buoyancy and drag forces. For illustration purposes, a jig bed consisting of 400 particles of two different densities is simulated. Preliminary results show that the model predicts the stratification of particles reasonably well.