Operating Reliability Assessment for Aero-engine Based on Condition Monitoring Information

Abstract

The aero-engine is a pivotal component of an airplane.The operating reliability assessment of the aero-engine is greatly meaningful in guaranteeing the flight safety.In practice,operating conditions of the aero-engines vary.It leads to that degradation degrees and failure times for different aero-engines are with great degrees of discreteness.Aiming at solving the problem that reliability assessment methods based on probability statistical analysis are inappropriate to assess the reliability of the individual aero-engine,a novel method using the condition monitoring information is proposed.The condition subspace of the aero-engine is constructed by utilizing the Kernel principal component analysis(KPCA) to describe the performance change of the aero-engine.The principal angles between the subspaces from the normal state and the damage state are calculated.The principal angles are transformed into operating reliability index by a proper mapping function.The proposed method is validated by using both the aero-engine run-to-failure data shared by National Aeronautics and Space Administration and the practical test data from a repair factory of aero-plane.The results illustrate the proposed method can assess the operating reliability of the aero-plane reasonably.It also offers valid approach for the operating reliability assessment of the aero-plane whose failure model subjects to small sample characteristics.