<title>Parametric analysis and testing of an electrorheological fluid damper</title>

Abstract

This study seeks to validate a predictive damper analysis, based on an idealized Bingham plastic shear flow mechanism, which incorporates leakage effects in an electrorheological (ER) damper. The ER bypass damper operates by a piston head pushing ER fluid out of a hydraulic cylinder and through an ER fluid bypass. The pressure to force ER fluid through the bypass produces the majority of the device's damping. The ER bypass is composed of an annulus formed from two concentric aluminum tubes. The application of a voltage potential between the aluminum tubes creates an electric field in the annulus that increases the yield stress of the ER fluid. The yield stress modifies the velocity profile of the fluid in the annulus and augments the damping coefficient of the device. The ER fluid damper contains a controlled amount of leakage around the piston head. The leakage allows ER fluid to flow from one side of the piston head to the opposite side without passing through the ER bypass. In this analysis, the leakage damping coefficient with incorporated leakage effects, predict the amount of energy dissipated for a complete cycle of the piston rod. Measured force verses displacement cycles for multiple frequencies and electric fields validate the ability of the non-dimensional groups and the leakage damping coefficient to predict the damping levels for an ER bypass damper with leakage.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.