Abstract:

In order to reveal the effects of thermal elastohydrodynamic lubrication ( EHL) on the fatigue reliability of rolling bearings,a method combining the response surface method ( RSM) with the secondary-order polynomial as well as the first-order second moment method ( FOSM) is proposed.In the investigation,first,by considering the temperature field influenced by the EHL effect,the thermal stress is mapped into the Hertz contact zone of the rolling bearing,and a model to analyze the contact stress of rolling bearing under the action of thermal EHL is established.Then,by taking into consideration the thermal EHL effect,the material properties and the randomness of fatigue strength correction factors,the fatigue reliability analysis of rolling bearing under the action of thermal EHL is implemented based on the stress-strength interference theory.As compared with the traditional Monte Carlo method with 1. 5 × 105 simulations,the proposed method gives a difference in failure probability of 2. 1 × 10 － 4,a relative error of 24. 4% and a relative time consumption of only 0. 15%.Moreover,the sensitivity analysis results agree well with the practical cognition,which means that the proposed method correctly reflects the influence of thermal EHL effect on the contact fatigue reliability of rolling bearings.

Key words: response surface method, thermal elastohydrodynamic lubrication, rolling bearing, contact fatigue, reliability