摘要
针对超声导波具有的频散特性,导致导波缺陷检测信号波包在结构中传播时发生的展宽及衰减现象,研究了如何利用频散补偿技术对检测信号进行处理,将被频散特性淹没的缺陷信息再现,以实现缺陷形状的辨识问题。在进行实验验证的过程中,利用导波检测管道中的双槽形人工缺陷,通过改变端面加载的压电传感器位置,接收一组时域回波信号,根据波数—频率关系对导波传播过程中的频散进行补偿后,再现缺陷的形状特征。
The dispersive effect of ultrasonic guided wave leads to the spreading and attenuation of the wave-packet propagated in a structure. Inspective signals with some information about defects are polluted by the effect. Application of dispersion compensation are studied for defect identification in this paper. According to this method, a non-axis symmetry end loading transducer can be used to excite an L(0,2) guided mode and receive its echo at one end of the pipe. By rotating this transducer with a specific space in the circumferential direction, twenty-four signals are received for dispersion compensation using the relation of wavenumber and frequency. Finally, we conclude that it is effective to help identify the shape of defects.
出处
《仪器仪表学报》
EI
CAS
CSCD
北大核心
2006年第z3期2095-2097,共3页
Chinese Journal of Scientific Instrument
基金
国家自然科学基金项目(10572009)
北京市自然科学基金项目(4052008)
北京市教委资助项目(4KM200410005003)
关键词
超声导波
频散补偿
缺陷检测
反演
guided wave dispersion compensation defect inspection identification
