Tang Binghui, Wang Yuemin, Gong Ruqing, Zhou Fan
College of Power Engineering, Naval University of Engineering, Wuhan 430030, China.
Sensors (Basel). 2024 Aug 20;24(16):5374. doi: 10.3390/s24165374.
Ultrasonic-guided waves (UGWs) in defective pipes are subject to severe coherent noise caused by imperfect detection conditions, mode conversion, and intrinsic characteristics (dispersion and multiple modes), inducing the limited performance of anomaly imaging. To achieve the high resolution and accuracy of anomaly imaging, a multi-strategy hybrid sparse reconstruction (MHSR) method based on spatial-temporal sparse wavenumber analysis (ST-SWA) is proposed. MHSR leverages the capability of ST-SWA to extract the wavenumber dispersion curves, thereby providing a more refined and precise search space for MHSR. Furthermore, it mitigates the impact of coherent noise by conducting dispersion compensation on the reconstructed signal. The sparse compensated signals through MHSR are employed for sparse reconstruction imaging. To validate the efficacy of the proposed method, UGW testing is performed on the defective steel pipe, and the results demonstrate the significant enhancement of anomaly imaging in defect resolution and positioning accuracy. The lowest estimated errors for axial and circumferential defect positions are 10 mm and 4 mm, respectively.
有缺陷管道中的超声导波（UGWs）会受到由不完善检测条件、模式转换以及固有特性（色散和多模式）引起的严重相干噪声影响，导致异常成像性能受限。为实现异常成像的高分辨率和准确性，提出了一种基于时空稀疏波数分析（ST-SWA）的多策略混合稀疏重建（MHSR）方法。MHSR利用ST-SWA提取波数色散曲线的能力，从而为MHSR提供更精细和精确的搜索空间。此外，它通过对重建信号进行色散补偿来减轻相干噪声的影响。通过MHSR得到的稀疏补偿信号用于稀疏重建成像。为验证所提方法的有效性，对有缺陷的钢管进行了UGW测试，结果表明在缺陷分辨率和定位精度方面异常成像有显著提高。轴向和周向缺陷位置的最低估计误差分别为10毫米和4毫米。
