超声导波技术因其单端激励、传播距离远,100%横截面检测等特点在长距离大范围结构的无损检测和健康监测中显示出良好的应用前景,但受制于理论及仪器技术目前基本只用于缺陷筛查,超声导波定量化检测技术尚未得到广泛研究和应用。针对导波检测中缺陷大小定量分析问题,提出一种基于匹配追踪算法的管道轴向缺陷大小定量分析方法。通过分析回波信号特性,合理选择字典分解出缺陷回波信号的两端面信号,并通过端面信号计算出轴向缺陷大小。通过有限元数值模拟以及利用MSGW磁致伸缩导波检测仪对人工刻伤的铝管进行算法验证试验,结果表明该算法的误差小于5%。
Ultrasonic guided wave technology shows a good prospect in the long distance and large-scale structure of the non-destructive testing and health monitoring, thanks to its advantages such as single-ended excitation, long propagation distance, 100% detection of cross section. Constrained by theory and instrumentation technology, ultrasonic guided wave is basically only used for defect screening, ultrasonic guided wave quantitative detection technology has not been widely studied and applied. Aiming at the quantitative analysis of defect size problem in guided wave inspection, it proposes a method based on matching pursuit for quantifying the severity of pipeline defect along axial direction. By analyzing the characteristics of the echo signal, the optimized dictionary is constructed to efficiently decompose the edge reflection components from defect reflection signal. The axial extent of defect can be then quantitatively evaluated by using obtained information. Algorithm validation experiments of finite element numerical simulation as well as detecting the artificial defects in the aluminum pipe by using MSGW magnetostrictive guided wave detector show that the algorithm of error is less than 5%.