Vibration Suppression Evaluation of Smart Journal Bearing Using Giant Magnetostrictive Actuators

Abstract

A new kind of smart hydrodynamic journal bearings with giant magnetostrictive actuators (GMA) is introduced. The static and dynamic displacement outputs of the designed GMA are up to tens of microns, about the same order of magnitude as the conventional journal bearing clearance. Vibration suppression of the new smart journal bearing is theoretically evaluated using a simple Jeffcott rotor-bearing system. Kinematic equations are set up including the magneto-mechanical coupling model for GMA. The bearing oil film force under large vibration is calculated using a fast and efficient non-stationary oil film database technique. The unbalance vibration orbit of the rotor center is simulated. A simple synchronous proportional control method for GMA with different control phases and gains is investigated. The suppress effect of unbalance vibration and improvement of oil whip unstable speed is evaluated. The simulation proves that the new journal bearing has better stability, and that rotor vibration can be actively suppressed.