Rub Related Nonlinear Dynamics in a Noisy Non-Smooth Jeffcott Rotor Model

Strong and discontinuous nonlinearities arising from friction, contact stiffness, clearances and unbalance excitation and random excitation due to parametric uncertainty make the dynamic analysis of a rotor-stator system complex. This paper presents the dynamics of a nonlinear and non-smooth Jeffcott rotor system. The effects of unbalance force, bearing clearance, rotor-stator impact, tangential rubbing, randomness in rotor parameters due to manufacturing error and assembly deviation are considered in formulating the equations of motion. Both normal impact and tangential rubbing between rotor and stator are modeled respectively as of Hertzian type and dry friction. The parametric uncertainty is modeled by appropriate white noise random processes.