The Electrical Transfer Characteristics of Electro-Rheological Fluids in the Squeeze-Flow Mode

In this paper the authors describe an experimental investigation to determine the electrical transfer characteristics of electro-rheological fluids in the squeeze-flow mode of operation. It has been shown previously that the squeeze-flow mode provides significantly greater mechanical forces than are available from ER fluids placed in shear. However, since the electric field varies as a function of the inter-electrode gap there is an additional need to understand the complex elec trical/mechanical interactions at work in squeeze-flow. The study confirms the need to account for the dynamics of the electrical source and shows how the frequency dependence of the capacitive and resistive terms associated with the squeeze-flow cell can be quantified through the use of suitable empirical expressions. The validity of the derived coefficients is demonstrated through the ability of models to predict the complex admittance transfer function of the ER squeeze-flow cell.