Interface-resolved simulations of particle suspensions in Newtonian, shear thinning and shear thickening carrier fluids

We have performed simulations via employing an Immersed Boundary Method (IBM) to study flows of noncolloidal spherical and rigid particles suspended in Newtonian, shear thinning and shear thickening fluids. We consider a linear Couette configuration to explore a wide range of solid volume fractions and particle Reynolds numbers. We show that the existence of a wide spectrum of the local shear rate and its dependency on the solid volume fraction and particle Reynolds number points to the deficiencies of the mean field argument in estimating the rheology of noncolloidal complex suspensions. We indicate the role of inertia at the microstructural level and include it in the closure for the suspension shear stress for both Newtonian and power-law suspending fluids.