旋转叶片异步振动全相位FFT辨识方法

A method for identifying rotating blade asynchronous vibration by all-phase FFT

基于叶尖定时的旋转叶片振动测量技术属于严重的欠采样方法。为实现旋转叶片异步振动辨识,分析了基于叶尖定时的异步振动信号模型,设计了一种利用全相位FFT分析技术的多传感器遍历的异步振动辨识方法,从理论上推导了全相位FFT以及多传感器遍历算法,并进行了计算机仿真验证。运用该方法在某型号航空设备的旋转叶片完成振动测量实验,实验结果表明,叶片异步振动辨识结果与叶片理论设计基本一致。成功解决了叶片异步振动欠采样问题,进一步完善了叶尖定时测振系统。

The technology of rotating blade vibration measurement based on bladetip-timing（BTT） is badly sub-Nyquist-sampled method.In order to identify rotating blade asynchronous vibration,the asynchronous vibration signal model based on BTT is analyzed.A method for identifying asynchronous vibration by multi-probes traversing used all-phase FFT technology is designed.The arithmetic of all-phase FFT and multi-probes traversing are deduced in theory,and also are validated in simulation by computer.The method is applied to vibration measurement experiment for a certain model of aerial equipment.The experimental results indicate that the identified results of blade asynchronous vibration are in accord with the designed results of the blade in theory.The problem of identifying blade asynchronous vibration in sub-Nyquist-sampling is solved,and the BTT system is ameliorated greatly.