摘要
为准确监测埋地管道缺陷,采用压电陶瓷换能器在埋地管道中激励出纵向模态超声导波进行缺陷监测研究,分析了超声导波在埋地管道中的传播规律并建立频散方程,通过数值求解绘制了埋地管道频散曲线。根据频散曲线性质选择纵向L(0,2)模态导波用于管道缺陷监测,通过建立试验系统对理论分析的正确性进行了验证,并将时间反转法引入埋地管道缺陷监测过程。现场试验结果表明:采用直接导波法进行埋地管道缺陷监测,由于管道周围土体的影响,导波能量将会有更多衰减,且干扰噪声变大,监测信号的信噪比降低;而采用时间反转法进行埋地管道缺陷监测,利用时间反转导波的时间和空间聚焦效应,缺陷反射回波信号幅值得到明显增强,更易于从干扰信号中进行提取、分析和定位。研究结论为提高超声导波对埋地管道缺陷监测能力提供了一条新途径。
In order to monitor the defects in buried pipelines accurately,the piezoelectric ceramic transducer was applied to excite longitudinal mode ultrasonic guided waves in buried pipelines.In this paper,the propagation of ultrasonic guided waves in buried pipelines was analyzed,the dispersion equation was established,and the dispersion curve of buried pipelines was plotted from numerical solutions.According to the properties of dispersion curves,longitudinal L(0,2)mode guided waves were selected for pipeline defect monitoring,a test system was established to verify the theoretical analysis,and the time reversal method was introduced into the buried pipeline defect monitoring.Field test results show that,when direct guided wave method was used to monitor the defects in buried pipelines,more guided wave energy attenuated,the interference noise increased and the signal-to-noise ratio of monitoring signals decreased.When the time reversal method was used,with the time and space focus effect of time reversal guided waves,the amplitudes of reflected echo signals of the defects were enhanced obviously,which are easier to be extracted,analyzed,and located from interference signals.The study conclusions provide a new approach to improve the ability of ultrasonic guided waves to monitor the defects in buried pipelines.
作者
徐阳
罗明璋
杜国锋
Xu Yang;Luo Mingzhang;Du Guofeng(Electronics&Information School of Yangtze University;School of Urban Construction,Yangtze University)
出处
《石油机械》
北大核心
2022年第5期127-133,共7页
China Petroleum Machinery
基金
国家自然科学基金项目“基于分布式压电陶瓷传感器的长输管道动力响应监测与损伤识别研究”(51778064)。
关键词
压电陶瓷换能器
超声导波
埋地管道
频散曲线
时间反转法
信噪比
piezoelectric ceramic transducer
ultrasonic guided wave
buried pipeline
dispersion curve
time reversal method
signal-to-noise ratio
