风扇叶片外物撞击瞬间转子振动响应分析

Analysis of Rotor Vibration Transient Response of Fan Blade Impact

为研究风扇叶片外物撞击对转子振动的影响,参照某发动机设计搭建了风扇转子试验器,并结合有限元计算和锤击法试验获得了叶片的动静频,开展撞击位置、风扇转速等因素对转子振动特性影响试验。结果表明:风扇叶片遭遇外物撞击瞬间,转子振动频谱中叶片动频附近频率成分幅值变化明显;相比转子轴向位置振动,径向位置振动对外物撞击的响应很敏感且幅值变化明显;随着风扇转速升高,转子振动中叶片动频成分幅值会增大,而转子振动幅值并不一定会增大,振动幅值与撞击叶片编号、撞击位置等因素密切相关。

In order to study the influence of external impact of fan blade on rotor vibration,a fan rotor tester was built with reference to the design of an engine,at the same time,the dynamic and static frequencies of the blades were obtained by finite element calculation and hammer test.The impact position,fan speed and other factors on rotor vibration characteristics were tested.The results show that when the fan blade is impacted,the amplitude of the frequency component near the dynamic frequency of the rotor vibration spectrum changes significantly;compared with the axial vibration of the rotor,the radial vibration is more sensitive to the impact and the amplitude changes obviously;with the increase of the fan speed,the amplitude of the dynamic frequency component of the blade will increase suddenly,but the amplitude of the rotor vibration does not necessarily increase,and the amplitude of the vibration is also closely related to the number of the impacted blade and the impact position.