Nonequilibrium structure of concentrated colloidal fluids under steady shear: leading-order response

The flow-induced microstructural distortions of dense colloidal dispersions under steady shearing are derived within a recent first-principles approach to the nonlinear rheology of colloidal fluids and glasses. The stationary structure factor is discussed to leading orders in shear rate . We find that shear affects the stationary structure whenever the dressed Peclet/Weissenberg number becomes appreciable; here τ is the structural or α-relaxation time. Close to vitrification, this predicts significantly larger shear distortions than expected from considering the bare Peclet number Pe₀; it compares with the diffusion time of a colloid at infinite dilution.