Transient Thermal Model for Rolling Bearing Considering Surface Microtopography

Temperature status is one of the important parameters for evaluating bearing performance. Accurately predicting the relationship between bearing temperature and design parameters is of great importance in health monitoring, bearing design, etc. To investigate the effect of the actual surface microtopography on the bearing temperature, a new transient thermal model was proposed considering the surface microtopography. Firstly, the bearing micro interface contact model under lubrication conditions was established and the influence of different working conditions on the oil film thickness and pressure in the micro contact area was analyzed. Then, a nonlinear dynamic model considering oil film thickness, oil film stiffness and time-varying friction coefficient was developed based on thermal elastohydrodynamic lubrication theory. Finally, the mechanical properties of bearing components and transient heat generation considering raceway microtopography were obtained. The results show that the influence of surface microtopography on bearing temperature cannot be ignored and the proposed model can predict the transient thermal characteristics of bearings more accurately.