Abstract The higher performance of the guided wave technique for non-destructive testing (NDT) and structural health monitoring (SHM) on large-scale engineering structures is still a requirement in industries. In this paper, the unidirectional excitation function of guided waves by adding many rings of transducers (even or odd number) is described to enhance the wave power output of the inspection system. A parametric analysis based on the wave superposition is developed to predict the maximum power output amplitudes depending on varied ring spacings between the transducer arrays in the different centre frequencies. The proposed approach is tested numerically and then validated through an experiment in which torsional wave mode T(0,1) is excited in a pipe by one, two and three rings of 24 transducers operating in time-delays and different amplitude factors. The performance of transducer arrays for increasing the power output of excitation in the forward direction and cancelling signals in the reserve direction has been evaluated using experimental measurements.

中文翻译：

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通过多环换能器的线性叠加增强导向扭转 T(0,1) 模式的单向激励

摘要 在大型工程结构上进行无损检测（NDT）和结构健康监测（SHM）的导波技术的更高性能仍然是工业界的需求。在本文中，描述了通过添加许多换能器环（偶数或奇数）的导波单向激励功能，以提高检测系统的波功率输出。开发了基于波叠加的参数分析，以根据不同中心频率下换能器阵列之间的不同环间距预测最大功率输出幅度。所提出的方法进行了数值测试，然后通过一个实验进行验证，在该实验中，扭转波模式 T(0,1) 在管道中被激发，两个和三个环的 24 个换能器以时间延迟和不同的幅度因数运行。已经使用实验测量评估了换能器阵列用于增加正向激励的功率输出和抵消反向信号的性能。