Reliability Analysis for Rotor Rubbing

The dynamic equations of the Jeffcott rotor with imbalance are concerned. The reliability of rotor systems with rubbing is examined. A statistical fourth moment method is developed to determine the first four moments of the system response and the state function. The distribution function of the system state function is approximately determined by using the Edgeworth series technique. Its reliability is obtained. The effect on the reliability of the shaft stiffness, the external damping coefficient, the degree of imbalance and the stator stiffness is studied. Numerical results are also presented and discussed.