基于模态声发射和小波变换的薄板中导波传播特性的实验研究  

Experimental Research on Guided Waves Propagation in Thin Plate Using Wavelet Transform and Mode Acoustic Emission

作　　者：焦敬品[1] 吴斌[1] 何存富[1] 费仁元[1] 李涌[1] 

机构地区：[1]北京工业大学机电学院,北京100022

出　　处：《中国机械工程》2004年第13期1179-1182,共4页China Mechanical Engineering

基　　金：国家自然科学基金资助项目 ( 19972 0 0 3;10 2 72 0 0 7);北京市自然科学重点基金资助项目 ( 3 0 110 0 1)

摘　　要：基于小波变换和模态声发射理论 ,通过声发射实验的方法确定了薄板中导波传播的弥散特性。通过分析声发射信号的Gabor小波变换幅度在时频空间分布特点 ,确定某一频率下某一模态导波到达传感器的时间 ,从而确定该频率下该模态导波的群速度 ,进而确定其弥散曲线。实验确定薄板弥散曲线与理论计算曲线较好吻合 。Based on the wavelet transform(WT) and the theory of mode acoustic emission, the dispersions of guided wave propagated in thin plate were investigated by acoustic emission experiments. The wavelet transform using Gabor wavelet was applied to the time-frequency analysis of disperse plate waves. It is shown that the peaks of the magnitude of WT in the time-frequency domain are related to the arrival times of guided waves. By utilizing the time-frequency data of the WT, the frequency-dependent arrival time of some mode guided waves to sensors was obtained,and the dispersion characteristics of guided waves were also obtained. It is demonstrated the wavelet transform is an effective tool for analysis the time-frequency characteristics of disperse waves.

关 键 词：小波变换 模态声发射 导波 弥散 

分 类 号：TG115.28[金属学及工艺—物理冶金]