Research on Multipoint Leak Location of Gas Pipeline Based on Variational Mode Decomposition and Relative Entropy

Yongmei Hao,Xinming Yan,Juncheng Jiang,Shuli Wang,Yongchao Rao,Zhanghao Du,Zhixiang Xing,Ehsan Ahmadi

doi:10.1155/2020/8868963

Abstract

Pipeline leak detection has always been a relatively difficult technical problem; especially in urban pipeline leak detection, there are still many problems to be solved. A multipoint leak detection and location method for urban gas pipelines based on variational mode decomposition and relative entropy was proposed. Firstly, the experiment pipeline system was built, and the original signal was collected by acoustic emission technology; then, a variational model method was used to decompose the signal to obtain multiple intrinsic mode function (IMF) components with different characteristic scales. According to the characteristics of relative entropy, each component was analyzed, the appropriate IMF component was selected, and the selected component was reconstructed to obtain the observation signal. The multipoint leakage location model of the urban gas pipeline was established. The number of source signals was estimated by singular value decomposition, and the leakage signals were separated; finally, the accurate location of leakage point was achieved by cross-correlation positioning. The results showed that the average relative error of the pipeline leak location results is 2.97%, and the leak location accuracy is significantly improved, achieving the purpose of precise location.

Highlights

Urban buried gas pipeline network, as one of the indispensable infrastructure of the city, has developed rapidly in many cities in recent years, and the scale of urban underground pipeline is getting larger
Introduction to the Experiment. e positioning test platform of pipeline leakage acoustic emission detection is mainly composed of a pipe network system and an acoustic emission detection system. e test pipeline consists of three U-shaped seamless steel pipes of different diameters. e specifications of the pipes are DN150, DN100, and DN65, and the total length is 135 meters
Aiming at the problem that the detection and location accuracy of multipoint leakage of urban gas pipelines is not high, this paper proposes a multipoint leakage location method for pipelines based on variational mode decomposition (VMD) and relative entropy

Summary

Introduction

Urban buried gas pipeline network, as one of the indispensable infrastructure of the city, has developed rapidly in many cities in recent years, and the scale of urban underground pipeline is getting larger. E multipoint leakage location method of urban pipelines uses the acoustic emission system to collect multipoint leakage source signals without excavation of the gas pipeline and uses the VMD method to decompose the leakage signals to effectively eliminate the interference of nonleakage signals such as noise. On this basis, a multipoint leakage location model for pipelines is established, and the leakage location of the pipeline is accurately calculated through crosscorrelation positioning.

Signal Extraction Based on VMD and Relative Entropy

Experimental Verification

Findings

Conclusion