A STOCHASTIC FINITE-ELEMENT METHOD FOR FATIGUE RELIABILITY-ANALYSIS OF GEAR TEETH SUBJECTED TO BENDING

A stochastic finite element method (SFEM) is developed for accurate st ructural reliability analysis. Using the second-order three-moment rel iability analytical model, this method takes into account such random factors as load, material parameters and especially geometry randomnes s. The calculation of the bending fatigue strength reliability of a ca ntilever beam is carried out as a numerical example to verify the pres ent method. Monte-Carlo FEM and SFEM based on the first-order second-m oment model are used in the example to compare with the proposed metho d. By incorporating the fatigue theory of gears, the present method is then used to analyze the bending fatigue strength reliability of a sp ur gear. The effects of random variables' coefficient of variation and skewness and the gear's correction factor (not random variable) on th e gear's reliability are also investigated.