航空发动机叶盘轴系统固有特性分析

Natural Vibration Analyse of Blade Disc-Shaft System in Aero-Engine

针对某航空发动机叶盘轴系统,建立了轴与叶盘不同距离、不同轴径的叶盘轴系统有限元模型,并进行了模态分析,计算叶盘轴系统的固有频率,分析了轴与叶盘相对位置和轴径对叶盘轴系统固有特性的影响,为将来叶盘轴系统试验器的设计提供理论依据.结果表明:叶盘轴系统振动包含3类模态,分别为叶片单独振动模态、叶盘轴耦合模态和叶盘耦合模态;随着轴与叶盘距离的增大,第1阶耦合频率变化相对稳定,第2阶耦合频率变化呈上升趋势.

For a certain aeroengine blade disc-shaft system,a finite element model of the blade disc-shaft system with different distances between shaft and blade discs and different shaft diameters are established.Then the modal analysis is carried out and the natural frequency is calculated.The effects of the relative position of the shaft and the blade disc and the shaft diameter on the natural vibration of the blade disc-shaft system were analyzed.It provides a theoretical basis for the design of system tester in the future.The analysis results indicated that the vibration of the blade disc-shaft system includes three types of modes:blade vibration mode,blade shaft coupling mode and blade disk-shaft coupling mode.With the increase of the distance between the axis and the blade disk,the coupled natural frequency of the 1st order is relatively stable,while the coupled natural frequency of the 2nd order is on the rise.