Abstract: The time-varying meshing stiffness variation can reflect the size of gear fault feature when the gear fault occurs. Therefore, the time-varying meshing stiffness is an important dynamic parameter in the process of gear transmission. A novel tooth crack meshing stiffness calculation method namely analytical-finite element method (A-FM) is presented. Considering the calculation accuracy of the analytical model of the meshing stiffness is low when the gear fault occurs, the stress intensity factor is introduced into the calculation of the meshing stiffness of the cracked gear in this paper. First of all, define the relationship between the stress intensity factors and the meshing stiffness, calculate the stress intensity factor near the crack tip by means of establish the gear contact model, then replace the part of fault stiffness in the analytical model with calculation result. This method is more accurate compare with analytical method and more effective compare with finite element method due to the stress intensity factor is sensitive to small local changes in the tooth root crack. Simultaneously, the six-degree of freedom dynamic model is established. Through the analysis of vibration response, the simulation results verify the feasibility of the proposed method.

Key words: analytical-finite element method, dynamical modeling, stress intensity factor, time-varying mesh stiffness