Multidimensional monitoring of gas pipeline leakage: an application of distributed multiparameter sensing based on hybrid UWFBG array

Traditional distributed optical fiber sensors (DOFSs) are limited to measuring a single parameter. Although distributed multiparameter sensing (DXS) systems, which integrate various sensing mechanisms, have been proposed, they remain largely confined to laboratory settings. In this study, we present a practical application of a novel DXS interrogation technique using hybrid ultra-weak fiber Bragg gratings (UWFBGs) for multidimensional monitoring of gas pipeline leakage. During the measurement cycle, which includes air inflation and leakage events, the wavelength variation of FBG on the main pipeline demonstrates a linear correlation between pressure variation and wavelength shift, with a coefficient of determination exceeding 0.999. The demodulated vibration and wavelength data enable comprehensive analysis for leakage localization and classification.