Nonlinear dynamic analysis of the central bevel gear transmission system in aero engine subjected to internal and external excitation

The research on the nonlinear dynamic characteristics of the central bevel gear transmission system was carried out for the requirement of the vibration control and fault diagnosis of the central bevel gear transmission system in an aero engine. This paper proposes the dynamic model for the first time in order to investigate nonlinear dynamic behavior of the central bevel gear transmission system, and the internal and external excitations are taken into account by using lumped parameter modeling. Time-varying meshing stiffness, gear backlash, and gear transmission error is included in the internal excitations, and the input power, the speed fluctuation of the driven shaft and the high-pressure rotor unbalance excitation are included in the external excitations. The effects of the external excitations on the complex nonlinear dynamic behavior of the system are studied. The results show that reasonable control of input power, speed fluctuations, and high-pressure rotor mass imbalance can improve engine vibration.