Nonlinear thermal effects on high-speed spindle bearings subjected to preload

• Nonlinear thermal characteristics of spindle bearing are analyzed by a new algorithm.
• The preload and bearing stiffness nonlinearly vary with temperature are estimated.
• Present method takes much less computational effort than the finite element method.

This paper presents a unified method to predict nonlinear thermal characteristics of a high-speed spindle bearing subjected to a preload. Based on a quasi-static model and finite different method, the change of thermal contact resistance, bearing parameters, and heat source with temperature per second is completely analyzed using a new algorithm. The bearing parameters and lubricant viscosity affected by time-varying temperature are updated in each time step. As a result, the thermal effects on contact angles, contact forces, the preload, and stiffness of the bearing are found. Moreover, our analysis results show that the estimated preload and bearing stiffness nonlinearly vary with the increase in temperature and the present method takes much less computational effort than the finite element method.