Vibration characteristic analysis of flexible rotor-bearing system subjected to external combined loads

This paper proposed a general five degrees of freedom dynamic model for investigating the vibration characteristics of flexible rotor-bearing system based on nonlinear elastic Hertz contact theory and Timoshenko beam theory by employing differential quadrature finite element and improved Newton-Raphson methods. The flexible rotor-bearing system is made up of stepped shaft and angular contact ball bearing (ACBB). First, the validation of the established model is verified by the existing literatures and finite element software ANSYS 18.2. Then, the dynamic behaviors of ACBB are discussed systematically for the investigations of the vibration behaviors of flexible rotor-bearing system provide reference. Finally, the vibration characteristics of flexible rotor-bearing system subjected to external combined loads are investigated from different perspectives thoroughly. The results show that the preload, external force, radial force and torque have important influence on the vibration behaviors of flexible rotor-bearing system. • A dynamic model of angular contact ball bearing is proposed by improved Newton-Raphson method firstly. • The dynamic model of flexible stepped shaft is established by DQFEM firstly. • The vibration behaviors of flexible rotor-bearing system are analyzed systematically firstly.