VISCOPLASTIC INCOMPRESSIBLE-FLOW OF FRICTIONAL-COHESIVE SOLIDS

A constitutive equation for the viscoplastic and incompressible flow of solids is presented. The equivalent viscosity includes cohesion, friction and fluidity parameters and is a non-linear function of both pressure and velocity. The model is employed in a steady-state flow formulation which is discretized by means of finite elements with velocities as nodal unknowns. Application is made to axisymmetric and two-dimensional gravity flow in hoppers, and the main parameters affecting the pressure distribution on the walls are identified. Results are compared with experiments and analytical models by other authors and show good agreement.