基于多通道声发射检测系统的管道气体泄漏位置定位方法研究

Study on the location method of gas leakage on pipeline based on a multi-channel acoustic emission detection system

摘要:

为了自主开发基于声发射检测原理的管道气体泄漏位置定位系统,研制了基于四通道声发射检测系统的管道气体泄漏模拟实验装置。在测定声波沿管壁传播速度基础上开展了管道气体泄漏检测实验,通过改变声发射传感器与泄漏孔的在管道壁面的相对位置来模拟泄漏孔位置的变化。采用小波去噪和滑动平均滤波方法对所采集的泄漏信号进行了处理,利用互相关算法求取了各传感器之间的延迟时间,进而基于时间差提出了泄漏孔的定位算法。实验结果表明模拟管道上泄漏孔的定位结果相对误差低于4.0%,该系统对泄漏位置的定位精度满足行业标准和国家标准的要求。通过优化设计声发射信号的采样频率、管道材质、管道壁厚和传感器端面面积等能够进一步提高定位的准确度。

Abstract:

To develop the pipeline gas-leakage location equipment based on the principle of acoustic emission detection, a pipeline gas-leakage experimental apparatus with four channels was developed. Based on the measurement of the propagation velocity of sound wave along the pipe wall, the gas-leakage detection experiment was carried out. Different gas-leakage locations were simulated by changing the relative position of the acoustic emission sensors and the leakage hole on the pipe wall. The Wavelet de-noising and moving average filtering approaches were adopted to process the sampled leakage signals, and the delay time between sensors was calculated through the cross-correlation algorithm. Then a location algorithm based on the time differences between sensors for the gas-leakage hole was proposed. It has been shown by the experimental results that the relative error of the location of the leakage hole on the simulated pipeline is less than 4.0%, and the positioning accuracy of the system to the leakage position meets the requirements of the industry standards and national standards. The accuracy of positioning can be further improved by optimizing the sampling frequency of the acoustic emission signals, pipe material, pipe wall thickness and face area of the sensor.