Leak Localization Method of Jet Fuel Pipeline Based on Second-Generation Wavelet Transform and Short-Time Energy Time Delay Estimation
Yongqiang Zhu, Xianming Lang, Lin Zhang, Zefeng Cai
Abstract
There is a large error in the acoustic propagation speed of jet fuel pipeline based on cross correlation analysis, which leads to poor positioning accuracy of the leak location. Therefore, a new leak localization method of jet fuel pipeline based on second-generation wavelet (SGW) transform and short-time energy time delay estimation is proposed. Using SGW transform to extract the leak acoustic signal to reduce the interference of external noise in this method, the short-time energy function is estimated to calculate the sudden change time range of leak acoustic signal in the time window, so as to find the sudden change time range containing the sudden change point information of leak acoustic signal. According to the threshold of short-time energy function, the accurate sudden change time of leak acoustic signal is determined. When the accurate sudden change times of three acoustic sensors are obtained, the leak position of pipeline is calculated by a leak localization formula. The proposed method does not need to estimate the acoustic propagation speed, and it can obtain more accurate leak localization accuracy of pipeline leak. The field experimental pipeline results show that the average error rate of jet fuel pipeline leak localization is reduced from 1.25% of the cross correlation analysis method to 0.1% of the proposed method.