Reliability Sensitivity Analysis of Rub Impact in Coupled Fault Rotor

Abstract

Abstract. On the basis of the dynamic equations of rotor system with pedestal looseness, rub impact and crack, the random response method of rotor system with pedestal looseness is researched. The method is based on stochastic perturbation theory and the Kronecker algebra, matrix calculus and random perturbation are used. the reliability of rubbing for the coupling fault of rotor system was studied by Applying stress-strength interference theory and fourth-order moment technology, and on the basis of reliability analysis, the reliability sensitivity of rub impact on coupled fault rotor system is discussed by combining the sensitivity technology . IntroductionMultiple fault often occur in the working process of rotating machinery at the same time, coupling faults can reduce the stiffness and strength of the rotor system, which will cause the occurrence of major accidents. So, research on the reliability sensitivity analysis of fault rotor system will have the theoretical and engineering-oriented significance for the rotating machinery [1].In the paper, the model of rotor system with coupled faults has been built. On the basis of the rotor system model, the random response method of rotor system with coupled faults is presented.The first four moments of the response and the state function are obtained using the statistical fourth-moment method. The reliability sensitivity analysis method of rotor system with coupled faults is presented. Numerical results are also presented and discussed.