Gautam Ambuj K, Yin Ching-Chung, Bhattacharya Bishakh
International College of Semiconductor Technology, National Yang Ming Chiao Tung University, Hsinchu 30010, Taiwan, Republic of China; Department of Mechanical Engineering, Indian Institute of Technology, Kanpur, U.P 208016, India.
International College of Semiconductor Technology, National Yang Ming Chiao Tung University, Hsinchu 30010, Taiwan, Republic of China; Department of Mechanical Engineering, National Yang Ming Chiao Tung University, Hsinchu 30010, Taiwan, Republic of China.
Ultrasonics. 2023 Dec;135:107137. doi: 10.1016/j.ultras.2023.107137. Epub 2023 Aug 19.
Guided wave electromagnetic acoustic transducers (EMATs) have a significant role in non-destructive testing and structural health monitoring. It can generate horizontally polarized shear waves propagating axially or circumferentially to characterize the shape and orientation of pipeline defects. This work proposes a new Chevron pattern-like coil structure design with a periodic permanent magnet (PPM) EMAT configuration. This specific design of the EMAT coil can generate a bi-directional shear horizontal wave (SH-wave) and reduce the side lobes. An optimal Chevron angle of coil wires assists in generating orthogonal propagatingwaveforms. These phenomena lead to the constructive interference of propagating waves and develop a resulting wave along the horizontal direction. A 3D FEM modeling and simulation have been carried out and validated with experimental results. The proposed EMAT results are compared with the conventional racetrack PPM EMAT model, which shows a significant improvement over conventional EMATs. A prototype of this proposed EMAT has been developed. It can be used to inspect surface defects in applications such as fuel transportation pipelines.
导波电磁超声换能器（EMATs）在无损检测和结构健康监测中发挥着重要作用。它可以产生沿轴向或周向传播的水平极化剪切波，以表征管道缺陷的形状和方向。这项工作提出了一种具有周期性永磁体（PPM）EMAT配置的新型人字形线圈结构设计。这种EMAT线圈的特殊设计可以产生双向水平剪切波（SH波）并减少旁瓣。线圈导线的最佳人字形角度有助于产生正交传播波形。这些现象导致传播波的相长干涉，并沿水平方向产生合成波。已经进行了三维有限元建模和仿真，并与实验结果进行了验证。将所提出的EMAT结果与传统的跑道形PPM EMAT模型进行了比较，结果表明其相对于传统EMAT有显著改进。已开发出这种所提出的EMAT的原型。它可用于检查诸如燃油输送管道等应用中的表面缺陷。
