振动环境中法兰连接结构状态的声发射辨识

在法兰连接结构振动试验的基础上,利用MATLAB对采集到的声发射信号进行处理,主要对重构后的信号进行分析。用特征频带与优势频带的概念,确定出小波包分解层数,得到声发射信号的频带分布特征。利用小波包能量百分比定量给出优势频带及其与扭矩之间的关系,发现能量随扭矩变化具有一定规律性,并提出用小波包能量谱变化率这一指标来表达其规律特征,从而实现对连接结构状态的辨识。

AE Identification of Flanged Connection Condition in Vibration Environment

On the basis of vibration testing of flanged connection structure,AE signals gathered were carried on processing with MATLAB,mainly the reconstructed signals.The concept of characteristic frequency band and the superiority frequency band were drew,the layer of wavelet packet decomposition were determined,and the frequency band distributed characteristic of acoustic emission（AE） were obtained.The percentage of wavelet packet energy was used to quantitatively get advantage band and the relationship between it and torque.The result indicates that the energy changes with the torque of a certain regularity,and it is proposed to express its rule and characteristic with wavelet packet energy spectrum rate of change this target,in order to achieve the identification of the connection structure condition.