Simple Shear Flow of Collisional Granular-Fluid Mixtures

摘要

This work deals with the simple shear flow of neutrally buoyant, rigid, Motionless spheres immersed in a viscous fluid that exchange momentum through inelastic collisions. It is shown how kinetic theories are able to provide a full analytical description of the flow, once the influence of the viscous fluid is taken into account in a simple way through the dependence of the collisional coefficient of restitution on the Stokes number. This allows the capture of the characteristics of the experiments performed by Bagnold 60 years ago and the interpretation of the macroviscous and inertial regimes described by the same author as the limits for the coefficient of restitution equal to zero and to the value valid in absence of the viscous fluid, respectively.