Research on stiffness characteristics of high speed angular-contact ball bearing considering elastohydrodynamic lubrication effect

The stiffness characteristics of high-speed angular contact ball bearing have important influence on the dynamic characteristics of an aero-engine's rotor system. To obtain them under oil lubrication condition, the elastohydrodynamic lubrication (EHL) effect on the stiffness characteristics of the ball bearing needs to be considered. Based on Jones pseudo-static mechanical model, a ball bearing stiffness calculation model is established by coupling the contact stiffness between ball and ring and its oil film stiffness, taking into consideration the EHL effect. The ball bearing stiffness calculation model is used to study the influence of EHL effect on the ball bearing stiffness. The exploration results show that the ball bearing stiffness with the EHL effect considered is obviously lower than the ball bearing's stiffness without considering the EHL effect. The ball bearing's radial stiffness is more sensitive to the EHL effect than the ball bearing's axial stiffness. With the EHL effect considered, the ball bearing stiffness decreases with increasing dynamic viscosity coefficient and pressure viscosity coefficient respectively. The ball bearing's radial stiffness increases with its temperature viscosity coefficient, but temperature viscosity coefficient has no effect on its axial stiffness. The influence of the EHL effect on the ball bearing's axial stiffness becomes more obvious when the rotor speed increases, but its influence on the ball bearing's radial stiffness is waning. Its influence on the ball bearing stiffness does not change with the load variation. © 2016, Editorial Board of Journal of Northwestern Polytechnical University. All right reserved.