Discharge of a granular silo as a visco-plastic flow

Abstract

Implementing a plastic rheology (using the μ(I)-rheology [5]) in a 2D Navier-Stokes solver, we simulate the continuum counterpart of the granular silo. Doing so, we observe a constant flow rate during the discharge and recover the Beverloo scaling. The results suggest that the constant discharge rate is due to the existence of a friction-dependent yield stress. Discrete simulations are performed using the contact dynamics algorithm. Systematic comparison of the velocity field and the inner deformations shows a good agreement between the two approaches. © 2013 AIP Publishing LLC.