Investigation of Cavitation Phenomenon in an Oscillatory Oil Squeeze Film

Abstract

For the journal bearing under dynamic loading or under large external excitation condition, the oil film will not be a simple form as normal divided into continue oil film area and cavitation area. Because of squeeze effect, the boundary of oil film changes dynamically and oil film pressure shows more complex. As reviewed in [1], also there are some “cavitation algorithms” [2,3] developed, the oil film performance under dynamic loading remains unclear. For the research on nonlinear analysis of rotor-bearing system, one of the important work is to obtain oil film performance model under large external excitation. In order to investigate cavitation phenomenon, especially how cavitation changing and how much tensile stress oil films can support, a parallel-plate oscillatory squeeze film test-rig was built where a high-speed CCD was used to capture the development of cavitation, and synchronously the oil film pressure and the oscillatory displacement were measured [4]. A new cavitation model also was proposed [1]. In this paper, the new model will be validated with the experimental data. Some phenomenon also was investigated theoretically with new model.