Temperature dependent fatigue-failure analysis of V-ribbed serpentine belts

The effect of temperature on fatigue life of V-ribbed serpentine belts is investigated. A predictive fatigue crack growth model to monitor progressive deterioration of initially small rib tip flaws subjected to thermal and mechanical loads is developed. The model is based on computational fracture mechanics and temperature dependent fatigue coupon tests. A global–local finite element strategy is used to compute the J-integral for a through-the-thickness crack in the rib tip. The finite element model accounts for thermal strains and temperature dependent properties of rubber. The three-dimensional global model is created with a coarse mesh using first order continuum elements while the local model for the rib crack is constructed with significantly finer mesh utilizing second order continuum elements. Maximum and minimum J-integrals calculated at two extreme configurations for a single belt running cycle is used to estimate the fatigue life of the belt. The J-integral and fatigue life estimates obtained from the analysis show that the life of the belt is significantly affected while operating at elevated temperatures.