A Study on New Identification Technique With Application to Squeeze Film Bearing System

Abstract

Two identification techniques, which are the Method of Feasible Directions (MFD) based on optimization concept and the Hybrid Method (HM) combining the merits of the State Variable Filter method (SVF) and MFD, are proposed for the parameters identification of rotor system with squeeze-film damper (SFD). The parameters of SFD, including hydrodynamic inertia, damping and stiffness, are identified and the results obtained by using MFD and HM are compared to those using SVF. The accuracy and efficiency of using these techniques are demonstrated by the experimental simulation with various noise levels and different initial values. The results indicate that the choice of initial values is of no significant effect on SVF method and the accuracy of SVF depends on the level of noise. However, for MFD method, it is almost independent of noise effect but significantly affected by the choice of initial values. The Hybrid Method (HM) is proposed to overcome these handicaps and found of better accuracy and efficiency than SVF and MFD. Then, it is highly recommended for the parameters identification of system with noise effect.