高速柔性转子-支承系统耦合动力特性计算与试验

Calculation and Test of Coupling Dynamic Characteristics of High Speed Flexible Rotor-Support System

随着航空发动机朝着高转速、高推重比方向发展,机匣壁设计得越来越薄,导致转、静子系统间的耦合振动问题突出,增加了发动机整机振动过大风险。针对某型高速柔性转子试验件系统,建立了柔性转子-支承系统的力学模型,采用有限元软件ANSYS对系统进行耦合动力特性分析,并开展了转子系统动力特性试验。结果表明:采用转子-支承系统耦合模型进行动力特性分析获得的峰值转速计算结果与试验结果差异为3%左右;由于支承系统存在共振,转子在工作转速范围内由2个峰值转速40%n、69%n变为3个峰值转速38%n、62%n和84%n,增加的峰值转速落在转速常用工作转速范围内,增加了系统振动过大风险。采用转子-支承系统耦合模型进行转子系统动力特性设计可以避免传统方法仅考虑转子动力特性而忽略了支承系统局部振动和耦合振动带来的振动问题,更为全面地指导发动机转子动力学设计。

With the development of aeroengine towards high speed and high thrust-to-weight ratio,the design of casing wall was be⁃coming thinner and thinner,which led to prominent coupling vibration problems between rotor and stator systems,and increased the risk of excessive engine vibration.According to a high-speed flexible rotor test piece system,the mechanical model of the flexible rotor-support system was established.The coupling dynamic characteristics of the system were analyzed by finite element software ANSYS,and the dy⁃namic characteristics tests of the rotor system were carried out.The results show that the difference between the peak speed calculated is about 3%by using the rotor-support system coupling model and the test results.Due to the resonance of the support system,the rotor has changed from two peak speeds of 40%n and 69%n to three peak speeds of 38%n,62%n and 84%n within the working speed range.The in⁃creased peak speed falls within the common working speed range,increasing the risk of excessive system vibration.Using the rotor-support system coupling model to design the dynamic characteristics of the rotor system can avoid the vibration problems of traditional method,which only considering the dynamic characteristics of the rotor and ignoring the local vibration and coupling vibration of the support sys⁃tem,thus guide the engine rotor dynamics design more comprehensively.