MODEL OF STRUCTURE AND CONDUCTION IN AN ELECTRORHEOLOGICAL FLUID UNDER FLOW

A theoretical model of moderately concentrated ERF suspensions under s hear flow is proposed which explicitly takes into account the effects of conductivity. Under an electric field a layered structure will form between the electrodes, with the solvent flow restricted to a central free-flowing region, and this gives rise to the field-induced viscosi ty increase. Using this model, the effect on the ERF properties of inh omogeneities of the particle conductivity can also be estimated. It is predicted that the addition of even small amounts of highly conductiv e particles to an ERF will dramatically reduce the field-induced visco sity increment, a phenomenon that has been observed in recent experime nts.