摘要
制约应力波导波技术应用于长输管道损伤检测的两个主要原因是信号处理技术和导波激励技术,针对应力波频散效应和外界噪声干扰使得管道损伤检测定位精度低的问题,采用了基于子波估计的反褶积技术处理管道导波测量数据。数值模拟和试验结果均表明,该方法可以有效地抑制导波频散,提高了管道损伤检测的定位精度。针对单一激励能量有限、检测信号的信噪比低等问题,采用了编码激励技术,设计了两种不同的编码激励信号,并将其应用到管道纵向导波传播模型中。数值模拟结果表明,编码激励技术能够有效地提高管道损伤检测的抗干扰能力和分辨率。
The frequency dispersion effects of the stress wave and external noise result in inaccurate positioning of the pipeline damage.To deal with the above issue the deconvolution method based on wavelet estimation is adopted to process the experimental data of the guided wave.The numerical simulation and experimental results have shown that this method can suppress the frequency dispersion of the guided wave effectively and improve the positioning accuracy in the pipeline damage detection.As a single exciter has limited energy and the measured signal has a lower signal-to-noise ratio,the coded excitation technique is applied.Two signals with different coding methods are designed and then used in a longitudinal wave propagation model of the pipeline.The numerical results have demonstrated that the coded excitation technique can improve the capability of anti-interference and resolution in the pipeline damage detection.
出处
《振动．测试与诊断》
EI
CSCD
北大核心
2014年第1期130-135,194,共6页
Journal of Vibration,Measurement & Diagnosis
基金
国家自然科学基金资助项目(61071041)
山东省自然科学基金资助项目(ZR2010FL005,ZR2012FM012)
关键词
管道损伤检测
子波估计
反褶积
编码激励
pipeline damage detection
wavelet-estimation
deconvolution
coded excitation
