Structure and rheology of semidilute suspension under shear

We study the structure and viscosity of a semidilute colloidal suspension under stationary shear. For a model hard-sphere suspension with no hydrodynamic interactions we obtain accurate results for the low-density limit of the steady-state structure factor and shear-rate-dependent viscosity coefficients. In contrast with predictions of the earlier theories, we find a nonzero distortion of the structure factor in the plane perpendicular to the flow direction. The observed changes of the structure factor are correlated with shear thinning of the suspension.