Based on the free boundary theory and variational method, this paper presents a Ritz method to compute the instantaneous hydrodynamic forces of a real bearing subject to any perturbed motions of the rotor. The given method manipulates the cavitation region by simply introducing a parameter to match the free boundary condition and, as a result, a very simple approximate formula of oil-film pressure were obtained leading to great saving of computing time. The numerical examples show the high accuracy of the proposed formulas. This oil-film force model is also used to analyze the nonlinear dynamics of a rigid unbalanced rotor with elliptical bearing support. The results well agree with those of the oil-film force model computed by the finite element method and the computing time is saved greatly.
A Ritz Model of Unsteady Oil-Film Forces for Nonlinear Dynamic Rotor-Bearing System
Contributed by the Applied Mechanics Division of THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS for publication in the ASME JOURNAL OF APPLIED MECHANICS. Manuscript received by the Applied Mechanics Division, Jan. 22, 2003; final revision, June 5, 2003. Associate Editor: D. A. Siginer. Discussion on the paper should be addressed to the Editor, Prof. Robert M. McMeeking, Journal of Applied Mechanics, Department of Mechanical and Environmental Engineering, University of California–Santa Barbara, Santa Barbara, CA 93106-5070, and will be accepted until four months after final publication in the paper itself in the ASME JOURNAL OF APPLIED MECHANICS.
Zheng , T., Yang , S., Xiao , Z., and Zhang, W. (May 5, 2004). "A Ritz Model of Unsteady Oil-Film Forces for Nonlinear Dynamic Rotor-Bearing System ." ASME. J. Appl. Mech. March 2004; 71(2): 219–224. https://doi.org/10.1115/1.1640369
Download citation file: