Vibration transmission and energy dissipation through the gear-shaft-bearing-housing system subjected to impulse force on gear

In this work, an eight-degree-of-freedom (DOF) dynamic model of the gear-shaft-bearing-housing system is established and the vertical vibration transmission and energy dissipation characteristics through the multiple transmitting interfaces under the impulse force due to gear fault are studied. The elastic deformations at the interfaces between gear and shaft, inner race and outer race, outer race and housing are formulated by the corresponding contact stiffness. The housing compliance is also included. A half-sine impulse force with two characteristic parameters as amplitude and time duration, which are associated with the defect type and size, is employed to represent the effect of gear fault on the system dynamics. The acceleration responses for different transmitting components as gear, inner race, outer race and housing are calculated for different impulse time duration, different impulse force amplitudes and shaft rotating speeds. The vibration transmission and energy dissipation through the multiple interfaces are characterized by the defined vibration transmission ratio and energy dissipation ratio. Obvious attenuation in acceleration magnitude is observed between the transmitting components from gear to housing. The maximum attenuation occurs at the transmission from inner race to outer race, while the minimum is between the outer race and the housing. The time duration of the impulse force determines the resonance and also the vibration transmission characteristics of the system. The energy dissipation increases nonlinearly with the amplitude of the applied impulse force. Results also suggest that the interface between inner race and outer race, and the interface between gear and shaft dissipated about 60% and 40% of the total energy, are the main sources of energy dissipation in the system. However, the shaft rotating speed has limited effect on the vertical impulse vibration amplitude, vibration transmission and energy dissipation. Experimental validation is performed, which supports the characteristics obtained from numerical results.