Rao Jing, Qiu Hangyu, Teng Guoyang, Al Mukaddim Rashid, Xue Jianfeng, He Jiaze
School of Engineering and Information Technology, University of New South Wales, Canberra, ACT 2600, Australia.
School of Engineering and Information Technology, University of New South Wales, Canberra, ACT 2600, Australia.
Ultrasonics. 2022 Aug;124:106764. doi: 10.1016/j.ultras.2022.106764. Epub 2022 May 23.
With the increasing use of high density polyethylene (HDPE) pipes in nuclear industry which puts safety at the forefront, ultrasonic array imaging methods play a vital role in the structural integrity of HDPE pipe materials. However, the viscoelastic attenuation of HDPE pipe materials significantly decreases the level of signals, leading to a low signal-to-noise ratio caused by electronic noise. In this work, a domain-adapted spatio-temporal singular value decomposition (STSVD) processing algorithm combined with the total focusing method is proposed to improve the ultrasonic array image quality. First, the real-valued radio frequency (RF) data or A-scan signals are demodulated into the complex analytic signals containing in-phase and quadrature (I/Q) components. Then, the STSVD processing algorithm is used to filter the I/Q data, and the filtered I/Q data is converted into RF signals. Finally, the total focusing method is applied to the processed RF signals to produce the image of the region under detection as a stage of post-processing. Experiments are carried out with an ultrasonic linear phased array in contact with the HDPE pipe materials containing multiple side-drilled holes and through-wall notches. Results show that the proposed method can produce images with high quality to provide good inspection and characterization of defects in highly attenuative materials, especially the deeper defects.
随着将安全置于首位的高密度聚乙烯（HDPE）管道在核工业中的使用日益增加，超声阵列成像方法在HDPE管材的结构完整性方面发挥着至关重要的作用。然而，HDPE管材的粘弹性衰减显著降低了信号水平，导致由电子噪声引起的低信噪比。在这项工作中，提出了一种结合全聚焦方法的域自适应时空奇异值分解（STSVD）处理算法，以提高超声阵列图像质量。首先，将实值射频（RF）数据或A扫描信号解调为包含同相和正交（I/Q）分量的复解析信号。然后，使用STSVD处理算法对I/Q数据进行滤波，并将滤波后的I/Q数据转换为RF信号。最后，将全聚焦方法应用于处理后的RF信号，以生成检测区域的图像作为后处理阶段。使用超声线性相控阵对含有多个侧钻孔和贯穿壁缺口的HDPE管材进行了实验。结果表明，所提出的方法可以生成高质量的图像，以便对高衰减材料中的缺陷，尤其是较深的缺陷进行良好的检测和表征。
