Characteristics of Electrorheological Fluid Flow in JournalBearings

Abstract

Under the influence of an applied electric field, the variation of apparentviscosity of electrorheological (ER) fluid flow causes ER effects. Accordingto the Bingham model, which is widely used for describing the rheologicalproperties of ER fluids, this variation should be very weak at high shearrates. To clarify the ER effects in ER journal bearings at high shear rate, anumerical study is presented. It is found that under the influence of theapplied electric field, ER effects in ER journal bearings can be affected bynot only the apparent viscosity of ER fluids but also the movement of yieldsurface in the clearance of ER journal bearing. In the case of low shearrate, both are effective on the lubricant film pressure of ER journalbearings. In the case of high shear rates, the main factor is the extensionof non-yield region in the bearing clearance.