Li Zhao, Jing Liwen, Wang Wenjie, Lee Pedro, Murch Ross
Department of Electronic and Computer Engineering, the Hong Kong University of Science and Technology, Hong Kong, 999077, China.
Department of Civil and Natural Resources Engineering, University of Canterbury, Christchurch, New Zealand.
J Acoust Soc Am. 2019 Jan;145(1):361. doi: 10.1121/1.5087703.
The influence of pipeline thickness and radius on the attenuation of guided waves in water-filled steel pipelines is investigated using theoretical analysis and experimental measurement. Attenuations of individual axisymmetric modes in unburied water-filled steel pipelines are predicted by an analytical model under different pipeline radius-thickness ratios. Model predictions indicate that attenuation of the fundamental mode increases as the ratio rises. This effect is investigated by finding the displacement variations under different ratios. Laboratory experiments were also carried out in four unburied steel pipelines with three distinctly different radius-thickness ratios using acoustic transducers to acquire signals uniformly spaced along the axis of the pipe. By applying the iterative quadratic maximum likelihood algorithm, the attenuations could be accurately estimated from the measurement data for individual modes. Experimental results show that attenuation of the fundamental axisymmetric mode is sensitive to radius-thickness ratio, but high-order modes are barely affected, agreeing with the model predictions mentioned in this paper. The characteristics of water-filled buried pipelines are also investigated using an analytical model to understand the relation between wave attenuation and the radius-thickness ratio.
采用理论分析和实验测量的方法，研究了管道壁厚和半径对充水钢质管道中导波衰减的影响。通过一个解析模型预测了未埋地充水钢质管道中各轴对称模态的衰减情况，该模型考虑了不同的管道半径与壁厚比。模型预测结果表明，基模的衰减随着该比值的增大而增加。通过研究不同比值下的位移变化来探究这一效应。还使用声换能器对四条具有三种明显不同半径与壁厚比的未埋地钢质管道进行了实验室实验，以获取沿管道轴线均匀分布的信号。通过应用迭代二次最大似然算法，可以从各模态的测量数据中准确估计衰减。实验结果表明，基本轴对称模态的衰减对半径与壁厚比敏感，但高阶模态几乎不受影响，这与本文提及的模型预测结果一致。还使用一个解析模型研究了充水埋地管道的特性，以了解波衰减与半径与壁厚比之间的关系。
