STOKESIAN DYNAMICS SIMULATIONS OF COLLOIDS UNDER SHEAR

Stokesian dynamics, SD, simulations of model colloidal dispersions und er shear flow are presented. The behaviour of the Ermak Rouse-level mo del, which has no many-body hydrodynamics, MBH, is compared with the E rmak-McCammon algorithm which introduces MBH at the Rotne-Prager far-f ield level. Despite the inclusion of far field many-body hydrodynamics , the model colloidal systems still form ordered phases under shear ve ry similar to those formed by the Rouse model, over what is now consid ered to be an unrealistically large part of the non-equilibrium shear rate vs. volume fraction phase diagram. There is even evidence that th ese many-body hydrodynamics promote the formation of ordered phases. W e conclude that it is essential to have a better representation of sho rt-range hydrodynamics (e.g. lubrication) forces in any realistic impl ementation of MBH in a SD simulation.