In this work, we propose to identify the relative role of the inclination of gravitational acceleration and the friction on the discharge flow rate of a granular media from a rectangular silo, by varying the silo geometry thanks to an inclined bottom which ends up at a lateral outlet. The study is motivated by a nuclear safety problem: a fuel rod (modelled by an elongated silo) accidentally releases fuel fragments (modelled by grains). We performed experiments where we measured independently the mass flow rate and the velocity profiles, together with discrete particle simulations and continuum simulations with a frictional rheology described by a mu(I) constitutive law and taking into account the wall friction. We study mono-layer flows and 3D flows and we propose an analytical model that predicts the discharge flow rate of particles from a rectangular silo with an inclined bottom according to its outlet aspect ratio and the bottom inclination angle.
Z Zou, Pierre Ruyer, Pierre-Yves Lagrée and Pascale Aussillous 2020 Discharge of a silo through a lateral orifice: Role of the bottom inclination versus friction Physical Review E 102, 052902.
Pascale Aussillous 