An intelligent method for contact fatigue reliability analysis of spur gear under EHL

HU Yun(胡贇)^{1, 2}, LIU Shao-jun(刘少军)^{1, 2}, CHANG Ji-hua(常继华)^{1, 2}, ZHANG Jian-ge(张建阁)^{1, 2}

(1. School of Mechanical and Electrical Engineering, Central South University, Changsha 410083,China;
2. State Key Laboratory for High Performance Complex Manufacturing
(Central South University), Changsha 410083, China)

Abstract:To complete the contact fatigue reliability analysis of spur gear under elastohydrodynamic lubrication (EHL) efficiently and accurately, an intelligent method is proposed. Oil film pressure is approximated using quadratic polynomial with intercrossing term and then mapped into the Hertz contact zone. Considering the randomness of the EHL, material properties and fatigue strength correction factors, the probabilistic reliability analysis model is established using artificial neural network (ANN). Genetic algorithm (GA) is employed to search the minimum reliability index and the design point by introducing an adjusting factor in penalty function. Reliability sensitivity analysis is completed based on the advanced first order second moment (AFOSM). Numerical example shows that the established probabilistic reliability analysis model could correctly reflect the effect of EHL on contact fatigue of spur gear, and the proposed intelligent method has an excellent global search capability as well as a highly efficient computing performance compared with the traditional Monte Carlo method (MCM).

Key words:reliability; contact fatigue; spur gear; artificial neural network (ANN); genetic algorithm (GA); elastohydrodynamic lubrication (EHL)