Experimental Identification of Linearized Oil Film Coefficients of Cylindrical and Tilting Pad Bearings

Abstract

The dynamic behavior of the rotating machinery supported by the hydrodynamic journal bearings is significantly influenced by the dynamic characteristics of the oil film. In the present work an efficient identification method is used to identify the stiffness and damping coefficients of the tilting pad and cylindrical journal bearings of a flexible rotor-bearing system. The method uses FRFs (Frequency Response Functions) obtained by the measurements and the finite element method. The accuracy and feasibility of the method were tested and demonstrated by theoretical simulation. The possible effects of oil-film inertia is also verified by the theoretical simulation. The method can be further extended to identify twelve linearized oil-film coefficients.