Research On Reliability Of High-pressure Turbine Rotor System In Aeroengines

As one of the key components of aircraft, high-pressure turbine rotor system operates under the abominable conditions of high temperature and mechanical loads in high speed, high load and high temperature environment and suffering from variable failure modes, which are great threats to safe flight. Therefore, reliability analysis of high-pressure turbine rotor system is needed in design. This thesis uses Failure Modes, Effect and Criticality Analysis(FMECA) method to analyze the reliability of high-pressure turbine rotor system. Firstly, this thesis carries out the FMEA analysis of high-pressure turbine rotor system which includes failure mode analysis of component units as well as their causes and effects on the system and the failure modes list which the severities are I and II grade. Then, this thesis apply fuzzy comprehensive evaluation in high-pressure turbine rotor system’s criticality analysis due to the defect of FMECA’ qualitative analysis. Each component’s hazard degree and its failure modes’ risk priority is calculated in the first level fuzzy comprehensive evaluation. In second level fuzzy comprehensive evaluation, high-pressure turbine rotor system’ hazard degree can be calculated based on each component’s hazard degree.On the basis of FMECA, this thesis analyzes the failure mode of highest hazard degree with Fault Tree Analysis(FTA) and puts forward some corresponding measures for improving the system’s design and reliability.