Rapid gravity flow of cohesionless granular materials down inclined chutes

This paper is concerned with the analysis of the flow of cohesionless granular materials down inclined chutes. The stress tensor is assumed to be composed of two contributions, a rate-independent Coulomb part and a non-linear dynamic or viscous part. Plausible forms are chosen for these two stress contributions; the rate-dependent viscous part is based upon previous viscometric experiments of the present authors. The equations of motion are solved for the velocity and solids concentration for the case of two-dimensional stress and velocity fields. The two-dimensional analysis is then extended in a simple but approximate way to handle the effects of friction on the vertical side walls of a rectangular cross-sectioned channel. The predicted velocities and flow rates are compared with experiments of Savage for flowing polystyrene beads and reasonable agreement is found.