激励条件对发动机转子叶片疲劳试验响应影响规律

Influence of Excitation Conditions on the Forced Vibration Test Response of Engine Rotor Blades

研究了航空发动机转子叶片振动试验中位移激励方向与叶片叶尖弦向之间夹角变化对叶片最大振幅、应力分布等的影响规律。数值分析和试验测试数据表明,叶片刚性固定时,叶片安装位置与激励矢量之间的位置相对关系对振型、表面应力分布无显著影响,一阶振型下,叶片表面展向应力分量占主导;叶片安装位置与激励矢量之间的位置相对关系影响激励与响应之间的传递函数,存在最佳的位置,使得叶尖振幅一定时,激励能量最小。研究结果对提高转子叶片疲劳性能评价技术具有参考价值。

The influence of the excitation condition on the aeroengine rotor blade response in fatigue test is studied.Numerical analysis and experiments test results show that in the rigid clamping condition,the relative relationship between the rotor blade clamping and the test device excitation load vector has no significant effect on the first-order natural frequency,mode shape and stress distribution.In the first mode shape vibration condition,the span stress component dominates the surface stress of the blade,the clamping influences the transfer function between excitation and response.There exists a clamping position,in which,minimum excitation energy is required when the vibration amplitude of blade tip reaches certain amount.The conclusion is of great significance to improve the rotor blade fatigue performance evaluation technology.