Nondimensional Analysis of Electrorheological Dampers using an Eyring Constitutive Relationship

This study presents nondimensional analysis of an Eyring constitutive model to describe the field-dependent behavior of an electrorheological (ER) damper. An ER damper having a damping level comparable to a shock absorber for a small-sized passenger car damper is manufactured, and its performance is modeled using the Eyring model. To accurately identify the rheological parameters of the Eyring model, a parameter identification method is used. The force versus piston displacement and velocity behavior of the ER damper are experimentally measured with respect to the applied electric field and excitation frequency. To validate the Eyring model, the experimental results are compared to the predictions of the damping force versus piston displacement and velocity behaviors for four different applied fields and excitation frequencies tested. In addition, a set of nondimensional variables to characterize preyield and postyield behaviors of ER or MR fluids are proposed and nondimensional analysis for the Eyring model is undertaken in this study.