Analysis of nodal-diameter traveling wave resonance characteristics of spur gear with thin web of casing under misalignment condition

Focusing on a pair of thin-web spur gears in an aero-engine turbofan’s accessory gearbox, this study investigates their high-speed traveling wave resonance characteristics. The simulation analysis method of traveling wave resonance of high-speed thin-web spur gears is formed, and the law of traveling wave resonance characteristics of thin-web spur gears under misalignment and high-speed conditions is revealed. Firstly, based on the static-modal coupling analysis, the natural frequency of the gear pair considering centrifugal force and contact stiffness is solved. Then, based on the explicit-dynamic algorithm and the theory of gear traveling wave resonance, the traveling wave resonance point prediction and dynamic calculation of high-speed thin-web spur gear are carried out. Finally, through the comparative analysis of modal prediction value, experimental value, and dynamic calculation value, the results show that the large axial force generated by the misalignment of the spur gear angle is the key factor to induce traveling wave resonance. There is a relative error of less than 8% between the modal prediction value, experimental value, and dynamic calculation value, which verifies the applicability and reliability of the established prediction method and explicit-dynamic model. It has certain theoretical support and engineering value for the study of vibration avoidance and the dynamic characteristics of the aviation gear system.