Rheology of Thickly-Coated Granular-Fluid Systems

We investigate the link between particle-scale dynamics and bulk behaviors of thickly-coated particle-fluid flows using computational simulations. We find that, similar to dense fully-saturated slurries, the form the rheology takes in these systems can carry signatures of interparticle collisions and/or interparticle viscous dynamics that vary solid fraction. However, we find significant qualitative and quantitative differences in the transitions of the system between what might be called viscous, collisional, and visco-collisional behaviors. We show how these transitions arise from changes in the `fabric,' e.g. strong force network, and the `granular temperature,' or fluctuation energy, and suggest extension of these frameworks to better elucidate other particle-fluid behaviors.