Vibration attenuation of rotor-bearing systems using smart electro-rheological elastomer supports

Abstract

Nowadays, capability of safe operation suiciently away from the critical speeds is one of the most important design requirements of rotating machineries. The focus of this paper is the application of smart electro-rheological -ER- elastomers to <br>rotor dynamics ield to reduce the vibration level of a rotor system. A Jefcott rotor, supported via two bearings at both ends <br>augmented with ER elastomers, is considered. A inite element approach, based on the Rayleigh beam theory, is used to <br>model the dynamics of the system, and the proposed model accounts for the rotary inertia, gyroscopic efects and shaft’s <br>internal damping. The ER elastomer supports are simulated with four-parameter viscoelastic model. The simulation results <br>reveal that the use of ER elastomer in the conventional bearing supports leads to downshifting of the critical speeds and a <br>considerable reduction in its corresponding vibration amplitude. Also, the stability limit speed of the system is improved <br>by employing the ER elastomer technology. To extend the stability region of the rotor system to higher operating rotational <br>speeds, a simple on–of control strategy is employed. The proposed control scheme determines the required real-time voltage to be applied at ER elastomers and guarantees low vibration amplitude over a wide frequency range. The novel idea of <br>using ER elastomers for vibration suppression of rotor systems can be fairly extended to other applications which sufer from <br>unwanted high amplitude vibrations.