151 / 2025-06-06 14:23:39

A Belief Reliability Analysis Method for Key Components of Turboshaft Engines

Belief reliability,Compressor rotor system,Performance degradation,Margin analysis,Opportunity measure

Special Sessions > SSL 07 Belief reliability theory and its application in smart operation and maintenance

The compressor rotor system of a turboshaft engine is crucial to flight safety due to its core position. However, its reliability assessment faces severe challenges from the coupling of multi-source heterogeneous (random and cognitive) uncertainties in geometry, load, assembly, and materials, as well as small sample data, which traditional probabilistic methods struggle to address effectively. This paper, based on belief reliability theory, constructs a reliability analysis framework for this rotor system. By systematically identifying key performance parameters and core uncertainty elements, the paper elaborates on the construction approach for interdisciplinary equations that incorporate aero-thermo-structural multi-physics coupling effects. Performance degradation models for bearing fretting wear and fatigue-creep interaction damage are developed based on physical mechanisms. A dynamic dual-constraint margin equation of rotational speed and deformation is defined. Furthermore, opportunity measure is employed to uniformly quantify and propagate mixed uncertainties. Through an illustrative case study of a typical compressor rotor system, the results demonstrate the capability of this methodological framework in handling small samples and mixed uncertainties. Under the set parameter conditions, the analysis identifies increased centrifugal force as a potential primary cause for reliability reduction under overspeed conditions. The blade root fillet radius and assembly clearance are identified as parameters with significant influence on system reliability. Moreover, the method can predict the evolution trend of system reliability, thereby providing an analytical approach and key node identification for condition-based maintenance decisions. This research offers new theoretical guidance and engineering analysis methods for the reliability design, life prediction, and maintenance of critical engine components.