The discharge flow in a cylindrical and a rectangular silo using both monodisperse and bidisperse mixtures of spherical glass beads is studied experimentally. The flow rate is measured using a precision balance for a large range of particles diameters, size ratio and outlet diameters. A simple physical model is proposed to describe the flow of bidisperse mixtures. It gives an expression for the flow rate and predicts that the bulk velocity follows a simple mixture law. This model implies that a mixture diameter cannot be simply dened. Moreover it is shown that bidisperse granular media allows for the transport of coarse particles below their jamming conditions.
Benyamine et al. Phys. Rev. E. 90 (2014) pdf
Pascale Aussillous 