Investigation on Nonlinear Behavior of a Rotor System with Friction Effect Due to End-Face Seal

The end-face seal is widely used in rotating machinery to minimize leakage between the rotating shaft and the housing, and it requires consideration in the system dynamics for successful design. In this paper, a nonlinear friction model of end-face seal considering rotor swing motion is proposed. By introducing this model, the nonlinear dynamic equations of an offset-disk rotor system with end-face seal are established. The effects of seal structure on rotordynamics are studied in detail from the perspective of mode and response. The results show that the response behavior of rotor system depends on the relative relationship between the input energy of sealing load and the energy consumed by system damping. Through the analysis of the key parameters, it is found that one can enhance the stability of the rotor-seal system by reducing contact radius, friction coefficient, and axial stiffness of seal structure or improving the damping ratio of rotor system.