19th Asia-Pacific Vibration Conference (APVC2021)

    The lubrication film between the raceway and rolling element in rolling bearing is point contact elastohydrodynamic lubrication (EHL), which transforms the stiffness and damping of the rolling bearing. Lubrication failure caused by local heating could lead to the local defects in rolling bearing and seriously affects the normal operation of machinery. Therefore, this paper conducted a coupling study on the tribological and dynamic performances of bearing-rotor system under thermal effect of lubricant. Considering thermal variation of film, comprehensive stiffness and damping and time-varying displacement, a dynamic rolling bearing model with local defect based on thermal EHL was established, then this model was verified by experiments. The influences of lubrication characteristics such as film thickness and temperature change on the bearing vibrations were analyzed. Compared with isothermal EHL, the results show that the film thickness and the film carrying capacity are reduced under thermal EHL. The lubrication film performances could affect the stability of rolling bearing, speed up the failure rates and reduce the service life. Hence the thermal effect of lubricant cannot be ignored. This model can accurately simulate the actual state of rolling bearing, which is contribute to the optimization and fault diagnosis of rolling bearing.