Relation between ordering and shear thinning in colloidal suspensions

• DOI: 10.1073/pnas.1301055110
• Publication Date: 2013-02-20T06:56:59Z
• Authors: Xinliang Xu; Stuart A. Rice; Aaron R. Dinner
• Keywords: Shear thinning; Layering; Dilatant; Hard spheres; Complex fluid; Thinning; Particle (ecology)

Colloidal suspensions exhibit shear thinning and thickening. The most common interpretation of these phenomena identifies layering the fluid perpendicular to gradient as driver for observed behavior. However, studies particle configurations associated with thickening cast doubt on that conclusion leave unsettled whether nonequilibrium are caused primarily by correlated motions or changes in packing structure. We report results Stokesian dynamics simulations hard spheres illuminate relation among suspension viscosity, rate, configuration. Using a recently introduced sampling technique systems, we show can be decoupled from layering, thereby eliminating thinning. In contrast, find there is strong correlation between two-particle measure stress. Our consistent recent experimental study.