Dynamic fatigue life assessment method for high-speed train gearbox housing
As the train's speed increases,the frequency range and energy of the wheel-rail excitation load rapidly escalate,leading to a pronounced elastic vibration response in the gearbox housing.This excitation load exacerbates the fatigue failure within the gearbox housing.To assess the dynamic fatigue life of the gearbox housing in the service environment,first,based on the modal superposition method,a fatigue life assessment method considering the dynamic characteristics of the gearbox housing was established,which can obtain the contribution of the single-order modal of the gearbox housing to the fatigue life.Subsequently,a model of the high-speed train gear transmission system was established,and the service vibration environment of the gearbox was simulated by applying the measured wheel vibration acceleration of the test line through the virtual exciter.Finally,the fatigue life of the gearbox housing was evaluated using the quasi-static superposition method and the modal superposition method,respectively.The results show that the results of the bench model are consistent with the waveform and main frequency characteristics of dynamic stress measured by the test line,and the relative error of stress is within 10%,which verifies the accuracy of the model.The fatigue life of the housing is greatly affected by the model in high frequency wheel-rail excitation environment,and the quasi-static superposition method cannot accurately reflect the fatigue life of the housing dangerous points such as the hanging ear root,and there are some key modals which affect the housing fatigue life significantly.These findings serve as a foundation for enhancing the fatigue performance of the train gearbox housing through dynamic design methods.
high-speed traingearbox housingbench modeldynamic fatigue life