NUMERICAL-SIMULATION OF INELASTIC FRICTIONAL SPHERES IN SIMPLE SHEAR-FLOW

A numerical program is developed to simulate an assembly of inelastic frictional spheres inside a control volume undergoing rapid shearing m otion induced by the top and bottom moving periodic boundaries. A stic king-sliding collision model is used to emulate binary collisions of r eal particles. After the flow has reached a steady state, ensemble ave rages of macroscopic properties such as translational and rotational g ranular temperatures, and kinetic and collisional stresses at differen t solids concentrations are obtained. The present results are compared with previous theoretical, numerical and experimental works, and favo urable agreement is found among them. The simulation results show that the stresses are anisotropic and decrease with decreasing coefficient of restitution and increasing friction coefficient. At high solids fr action, above about 0.5, there exists a critical concentration where t he layering effects of particles, the formation of high-density micros tructures and the increase in correlation of particle velocities are t he major causes of abrupt changes in flow properties.