Multi-state reliability analysis of rotor system using Semi-Markov model and UGF

In order to accurately reflect the performance degradation law of the aero-engine rotor system during its life span, a novel multi-state reliability analysis method for rotor system is proposed. The method is based on the combination of the Semi-Markov model with UGF technique. The Semi-Markov model is used to describe the performance degradation process of the components of the rotor system. The UGF technique is utilized to exhibit the relationship between the state performance and the performance probability of the components. Furthermore, the UGF of the entire rotor system is obtained by simplifying the system structure with the modularized method. Therefore, the reliability of the rotor system at different task performance levels can be evaluated easily. A practical case study based on a turboprop engine rotor system is performed to illustrate the implementation and efficiency of the proposed reliability analysis method. Meanwhile, compared with the conventional method, the analysis results indicate that the proposed method can reflect the performance degradation process of the rotor system more veritably and effectively