Abstract Leak location using correlation-based acoustic method is a common practice in gas-filled pipelines, which will be extremely effective when the leakage-induced acoustic wave has a constant propagation speed. This premise is often not satisfied as result of multi-modal and dispersive nature which will cause acoustic speed to vary with frequency and modal type. In this work, the multi-modal identification based on selection of coherent frequency band is proposed for improving leak location in gas pipelines. The dispersive and multi-modal characteristics are studied by theory analysis and experimental validation to give understanding of the reason that correlation-based leak location has a larger error at times. The results demonstrate that the multi-modal type can be identified from law of acoustic speed variation by selection of coherent frequency band and multi-modal and dispersive characteristics are the main cause of a larger leak location error.

中文翻译：

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基于相干频带选择的充气管道泄漏声振动多模态识别

摘要 基于相关性声学方法的泄漏定位是充气管道中的一种常见做法，当泄漏引起的声波具有恒定的传播速度时，这种方法将非常有效。由于多模态和色散性质会导致声速随频率和模态类型而变化，因此这个前提通常不满足。在这项工作中，提出了基于相干频段选择的多模态识别，以改善天然气管道的泄漏定位。通过理论分析和实验验证研究色散和多模态特性，以了解基于相关性的泄漏位置有时具有较大误差的原因。