Non Linear Transient Response of a Flexible Shaft Controlled by Electro-rheological Hydrostatic Squeeze Film Dampers

Abstract

The aim of this research is to study the non-linear dynamic behaviour of a flexible shaft supported by hydrostatic squeeze film dampers which are filled with a Negative Electro-Rheological fluid (NERF). In order to study the effect of the electro-rheological fluid on the dynamic behaviour of a flexible shaft, a non linear model of a hydrostatic squeeze film damper has been developed and the results are discussed and compared with the linear model which is restricted to only small vibrations around the equilibrium position. A new control system is proposed to reduce the transient response of the shaft, by applying an electric field in order to modify the viscosity of the NER fluid in the hydrostatic journal, and thus control its damping. The results of this control show that it is possible to effectively monitor the electric field and the viscosity of the fluid inside the hydrostatic squeeze film dampers (HSFD) for controlling flexible shaft vibration.