Rheology of inertial viscohesive granular flows: insights from numerical simulations

In the presence of cohesive and viscous interactions between particles (wet particles, sticky particles), a granular flow is governed by several characteristic time and stress scales that determine its rheological properties (shear stress, packing fraction, effective viscosities) and texture variables (coordination number, contact network anisotropy). In this talk, based on extensive discrete element simulations, we show that the shear strength is proportional to the total confining stress (sum of external and cohesive stresses) and a unique function of the inertial, Stokes and cohesion numbers. This function extends therefore the inertial number used previously for dry cohesionless granular flows and suspensions to more complex flows. We also show that a similar scaling describes the texture parameters. Lastly, we discuss its relevance to non-Brownian suspensions.