A GENERALIZED PRESENTATION OF VALVE AND CLUTCH DATA FOR AN ER FLUID, AND PRACTICAL PERFORMANCE PREDICTION METHODOLOGY

In previous papers a technique for comparing the performance of a part icular electrorheological (ER) fluid in different situations was deriv ed from steady, laminar, shear and flow mode experimental data and sta tic cell tests. By plotting non-dimensional Hedstrom Number (He) and F riction Coefficient (Cf) against Reynolds Number (Re) via use of the B ingham plastic constitutive equation, one continuous and overlapping r elationship was shown for constant field excitation over a range of op erating conditions and geometries. In the present work the same treatm ent is extended to a different fluid, of higher solid volume fraction and different constituents, which was tested on different instruments at a different uniform temperature, so as to attest the generality of the technique. In doing this the methodology of converting low shear r ate Couette viscometer data to practical flow valve performance predic tions is illustrated.