Engine performance degradation often causes changes of performance parameters, which leads to the change of load spectrum in completing the same mission and affects life prediction of the engine structure. At present, the above factors have not been considered in the process of compiling the load spectrum of the whole machine life test, resulting in a large error between life prediction results and field test results. To address this problem, based on the construction of a turbofan engine model that integrates overall performance degradation and dynamic performance correction is constructed, mainly analyzing dynamic correction of engine performance by tip clearance prediction method considering wear and creep. On this basis, a load spectrum correction method for turbofan engine considering performance degradation is proposed. The engine load spectrum for the typical flight mission profile is calculated. The results show that after 3 000 cycles of engine operation, the inlet temperature of the high-pressure turbine corrected with the model proposed in this paper is 0.69% higher than that with the traditional model. Compared with the original spectrum, the corrected load spectrum has a 4.90% reduction in the high-pressure shaft speed at the maximum state, a 2.95% increase in inlet temperature of the high-pressure turbine, and a 21.05% increase in duration of the maximum state. The goal of load spectrum correction considering performance degradation is shown to be achieved.

This paper studies on a division method of the whole aeroengine loading spectrum flight mission segment and rotor speed mission segment, which is based on the actual flight actions and related to the flight operations of aeroengine and is suitable for the variable-speed aeroengines such as turbojet and turbofan. Through the research, the aeroengine loading spectrum operation-related mission segments can be divided, which can provide important data basis for the life research on the structures which are sensitive to flight maneuver (such as the main shaft, large gearbox and installation section), lay a foundation for the simulation, compilation and prediction of the whole aeroengine loading spectrum. Firstly, based on the summary of basic flight actions in actual flight, the division of flight mission segment was realized by programming. Moreover, the aeroengine rotor speed mission segments, associated with flight actions and missions, were divided based on the flight mission segment division results. Besides, the efficiency and accuracy of the mission segment division results were verified by adopting measured loading spectrum data. Finally, the characteristics of speed mission segment division results were compared and analyzed in tables and figures. The comparison results show that the characteristics of similar speed mission segments are similar, while the characteristics of different speed mission segments are different. And the shapes of similar mission segments vary to the change of flight actions and operations, which can reflect the operation-related feature of the segments.