PCI Reverberation Suppression Method for Boiler Tube Leakage Based on Acoustic Signal Correlation

Abstract

The safe and economical operation of boiler units is adversely affected by boiler tube leakages, making the accurate localization of leakage points crucial. In the confined space of the boiler, the precision of time delay estimation is challenged by the interference from the superposition of boiler tube leakage sounds and reverberations, which affects the acoustic localization accuracy of leakage sources. To address this issue, the principal component inverse (PCI) method is employed to suppress the reverberation in boiler tube leakage sounds, and a PCI rank selection method based on the correlation of leakage sound signals is proposed, leveraging their similarity. The superiority of the proposed method in reverberation suppression is proved by comparing the time delay estimation results of the generalized cross-correlational (GCC) method based on the maximum likelihood (ML) weighting function, the GCC method based on the smoothed coherence transform (SCOT) weighting function, the PCI threshold method, and the PCI rank selection method based on signal correlation. The minimum and average absolute error (AE) for time delay estimation are reported as 0.014 and 0.136 ms, respectively.