Flow and rheology of frictional elongated grains

Abstract

The rheology of a 3-dimensional granular system consisting of frictional elongated particles was investigated by means of discrete element model calculations. A homogenous shear flow of frictional spherocyliders was simulated, and a number of rheological quantities were calculated. In the framework of the μ(I) rheology, the effective friction was found to be a non-monotonic function of the aspect ratio for interparticle friction coefficient μ p ≲ 0.4, while it was an increasing function for larger μ p. We reveal the microscopic origin of this peculiar non-monotonic behaviour. We show the non-trivial dependence of the velocity fluctuations on the dissipation regime, and trace back the behaviour of the normal stress differences to particle-level quantities.