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.
