基于等角度重采样的非稳态振动数据分析方法研究

Research on unsteady state vibration data analysis method based on equal angle resampling

在俯冲拉起、地面开车发动机不同状态之间切换等某些特殊状态下,直升机动部件的旋转频率是个变化量,采用傅立叶变换或者傅立叶级数展开算法进行频谱计算,得到的是对应数据的均值,由于频率在时刻变化,所得结果并不能真实反应这一过程中的振动量值。为解决这一问题,本文以旋翼转速为基准,引入等角度重采样方法对振动数据进行阶比分析,得到了不同阶次频率的真实振动量值,为特殊状态下的振动数据分析提供一种分析手段。

The rotation frequency of the helicopter moving parts is a variable in some special states,such as dive-hike and switching between different states of ground starting engine.Fourier transform or Fourier series expansion algorithm is used to calculate the spectrum,and the average value of the corresponding data is obtained.Because the frequency changes with time,the results can’t reflect the vibration values in this process.In order to solve this problem,this paper introduces the method of equal angle resampling to analyze the vibration data by order ratio,and obtains the real vibration values of different order frequencies,which provides a method for the vibration data analysis under special state.