突加高能载荷作用下航空发动机结构动态响应及安全性综述

航空发动机在服役期间可能遭受鸟撞、叶片丢失等突加高能载荷的作用,造成发动机整机/部件动力学特性恶化和关键构件的损伤,危及发动机的结构安全性。本文从突加高能载荷复现方法与传递规律、突加高能载荷作用下转子/整机结构响应研究、突加高能载荷作用下关键构件损伤机理三个方面综述了现有研究工作,并针对近年来发展的抗突加高能载荷的安全性设计方法进行了探讨,最后分析了突加高能载荷问题的科学本质及发展趋势,为突加高能载荷作用下航空发动机安全性设计提供了重要参考。

Review on Dynamic Response and Safety of Engine Structure under Sudden High Energy Load

In order to establish the blade flutter suppression engineering design method, the correlation between blade flutter characteristics and structural parameters of a high-pressure compressor rotor blade was investigated. The energy method based on the phase lagged boundary condition and the eigenvalue method was used to analyze the aeroelastic stability of the prototype blade. By analyzing the unsteady aerowork density distribution under near stall condition, the effects of design parameters such as radial distribution of the blade stagger angle, chord length and tip clearance were investigated to clarify the influence and its extent of each parameter on the flutter, so as to improve the aerodynamic damping. The results show that the tip clearance has the greatest influence on aerodynamic damping, the stagger angle takes the second place, and the chord length is the least. The variation of aerodynamic damping with tip clearance is not monotonous, so there exists a tip clearance to minimize the blade aerodynamic damping, where the blade aeroelastic stability is the worst. Reducing the attack angle and increasing the reduced frequency can improve the aerodynamic damping. In the design phase, the attack angle can be reduced by adjusting the stagger angle, and the reduced frequency can be increased by increasing the chord length. In consideration of the influence on the aerodynamic performance, the change of the attack angle is usually less than 5°. In addition, when adjusting the chord length and tip clearance, ensure that all structural components will not be collided.