Disorder and order in sheared colloidal suspensions. II. Stochastic simulations

Motivated by predictions of previous theoretical work [B. Morin and D. Ronis, Phys. Rev. E 54, 576 (1996)] we perform two dimensional stochastic simulations of sheared colloidal suspensions, governed by stochastic differential equations based on simple symmetries such as detailed balance (or time reversal symmetry of the action), which take the form of a modified fluctuating Navier-Stokes equation describing the local velocity of the fluid, coupled to a generalized convective-diffusion equation for the colloid number density. The results of the stochastic simulations are in agreement with earlier results based on the same model equations: specifically, there exists a transition in the homogeneous colloidal system to a layered phase at high shear rate and packing fraction. Additional insight is obtained through the analysis of the approximate equations for the first and second moments, derived perturbatively from the Fokker-Planck equation. [S1063-651X(99)14502-1].