Brownian-dynamics simulation studies of a charge-stabilized colloidal suspension under shear flow

Abstract

We have carried out Brownian-dynamics simulations of a charged colloidal suspension under oscillatory shear flow with both Couette and Poiseuille velocity profiles. We show that in the "steady-shear" limit, for both of the velocity profiles, the enhancement of the self-diffusion coefficient in directions transverse to the flow shows a crossover from a γ² dependence to a γ^½ dependence as the shear rate γ increases. The magnitude of the enhancement is a function of the interparticle interaction strength. There is a layering tendency in the direction of the velocity gradient for Couette flow, while such a tendency is not that prominent for Poiseuille flow.