Study on leakage location of directly buried heating pipelines by reconstructed VMD components based on energy analysis

To improve the accuracy of acoustic wave method for the directly buried heating pipeline leakage location in the complex noise environments, this paper proposes a leakage location method for heating pipelines based on energy analysis to reconstruct the effective modal components, that is, the variational mode decomposition (VMD) is used to adaptively decompose the detection signals into a group of intrinsic mode functions (IMF), identify and extract the effective modal components with leakage features,and complete the signal weighted reconstruction through energy proportion analysis. The leakage tests and engineering measurements show that the average location deviation by the conventional VMD leakage location method is 1.57 m while that of the proposed method is 0.51 m, along with their relative deviations of 8.42% and 2.75%, respectively. The leakage location accuracy of the proposed method is improved by 67.34%. In the engineering measurements, the conventional VMD method fails to find the leakage location of the pipeline, while the proposed method finds the leakage location and its location deviation is 1.78 m different from the actual location. The proposed method can effectively suppress the residual noises in the effective modal components, reduce the influence of noise components on the leakage location,and improve the leakage location accuracy of heating pipeline in the complex noise environments.