Field Identification of Dynamic Coefficients of Journal Bearings on Flexible Rotor-Bearing System

The displacements at the bearing locations play an important role in identifying the dynamic coefficients of the journal bearing. In this paper, an identification method for the oil-film dynamic coefficients is presented. First of all, a discrete state-space model of the bearing-rotor system is generated. Secondly, Kalman filter technique is used to obtain the displacements of the bearing locations. Then, these estimated responses are adopted to identify the dynamic coefficients. Finally, a comparison is developed between the identified results and the theoretical value. The results showed that the present method has high accurate for the identification of the dynamic coefficients, especially, for the direct dynamic coefficients.