Gas pipeline leak localization based on single-sensor modal acoustic emission and joint time–frequency analysis of Gabor-SPWVD

Abstract

Leakage accidents in gas pipelines not only result in significant property losses but also pose severe safety hazards. Thus, reliable leak localization technology is of great importance. Gas pipeline leak localization based on single-sensor modal acoustic emission and joint time–frequency analysis of Gabor-Smoothed Pseudo Wigner-Ville Distribution (Gabor-SPWVD) is proposed. First, an acoustic wave dispersion model is established based on the pipeline guided wave theory. The target modes and their feature frequency bands are identified through modal analysis. Then, a joint time–frequency analysis based on Gabor-SPWVD is performed and the time difference of arrival of the L(0,1) and F(1,1) modes is extracted from the time–frequency images. Finally, a single-sensor multimodal leak localization method is achieved based on the dispersion curves, group velocities, and time difference of different target modes. In the simulations, by comparing the modal time–frequency images of different pipe diameter and wall thickness, the results show that the time–frequency characterization capability of the proposed method is superior to that of the traditional methods. To verify the effectiveness of the proposed method, experiments were carried out. The experiments compared the single sensor multimodal localization performance under the conditions of different pipeline pressures and propagation distances. The experimental results show that the proposed method can effectively improve the time–frequency analysis capability and suppress the influence of cross interference terms, so as to accurately extract the time difference of arrival of the L(0,1) and F(1,1) modes for leak localization. The localization error of the proposed method is less than 6%.