喷气客机涡轮风扇发动机的振动诊断与改进

通过动态分析和现场测试对一喷气客机的发动机振动作出诊断，发现涡轮叶轮的变柔导致其极转动惯量显著下降，因而改变发动机的动态特性，使其临界转速接近飞机的巡航转速，产生不应有的振动和噪声。文章提出了具体改进方案，已为研制单位采用。

Vibration Diagnosis and Improvement of a Jet Aircraft Turbofan Engine

This paper clarifies vibration diagnosis of a new jet aircraft turbofan engine by means of dynamic analysis and field test, it is found that the tendency of turbine wheel to become flexible can lead to great decrease in its polar moment of inertia. Then, the dynamic behavior of the engine will be changed and one or more of its critical speeds may be close to the cruising rotating speed of the new jet aircraft. Thus, an unsatisfactory noise level arises from the strong vibration of the engine during cruising flight of the prototype. Two effective improvement measures are presented, and have been accepted by the manufacturer.