Franklin Mansur Rodrigues Filho Jorge, Tremblay Nicolas, Soares da Fonseca Gláucio, Belanger Pierre
Department of Mechanical Engineering, Universidade Federal Fluminense, Niteróy 24220-900, Brazil.
Department of Mechanical Engineering, École de Technologie Supérieure, Montreal, QC H3C 1K3, Canada.
Materials (Basel). 2017 May 19;10(5):551. doi: 10.3390/ma10050551.
Structural health monitoring (SHM) is emerging as an essential tool for constant monitoring of safety-critical engineering components. Ultrasonic guided waves stand out because of their ability to propagate over long distances and because they can offer good estimates of location, severity, and type of damage. The unique properties of the fundamental shear horizontal guided wave (SH₀) mode have recently generated great interest among the SHM community. The aim of this paper is to demonstrate the feasibility of omnidirectional SH₀ SHM in a thin aluminum plate using a three-transducer sparse array. Descriptions of the transducer, the finite element model, and the imaging algorithm are presented. The image localization maps show a good agreement between the simulations and experimental results. The SH₀ SHM method proposed in this paper is shown to have a high resolution and to be able to locate defects within 5% of the true location. The short input signal as well the non-dispersive nature of SH₀ leads to high resolution in the reconstructed images. The defect diameter estimated using the full width at half maximum was 10 mm or twice the size of the true diameter.
结构健康监测（SHM）正在成为持续监测安全关键型工程部件的重要工具。超声导波因其能够长距离传播以及能够对损伤的位置、严重程度和类型提供良好估计而脱颖而出。基本水平剪切导波（SH₀）模式的独特特性最近引起了结构健康监测领域的极大兴趣。本文的目的是展示使用三换能器稀疏阵列在薄铝板中进行全向SH₀结构健康监测的可行性。介绍了换能器、有限元模型和成像算法。图像定位图显示模拟结果与实验结果吻合良好。本文提出的SH₀结构健康监测方法具有高分辨率，能够在真实位置的5%范围内定位缺陷。短输入信号以及SH₀的非色散特性导致重建图像具有高分辨率。使用半高全宽估计的缺陷直径为10毫米，是真实直径的两倍。
