FBG strain sensing technology-based gas pipeline leak monitoring and accurate location

There are great security risks in urban natural gas transportation. In the event of a leak, the consequences are beyond imagination. At present, the accurate location of natural gas pipeline leakage is still a challenging task. Therefore, in the presented study, a pipeline leakage model is established, and the influence of pipeline leakage pressure, leakage diameter and leakage location on strain is elaborated. An NPW detection method based on fiber grating strain sensing technology is proposed, and the inflection point is extracted by empirical mode decomposition (EMD) method. The results show that distributed fiber grating strain sensing technology can effectively detect pipeline leakage, and the relationship between leakage pressure and maximum strain difference is linear, which is consistent with the theoretical deduction. The size of the leakage hole diameter and the location of the leak have minimal impact on the maximum strain difference, which has a maximum variation of 4.0με. It also indicated that the average positioning accuracy of this method is less than 0.5 m, and the positioning error is between 3.96 % and 7.36 %. Experimental results verify the effectiveness of this method in gas pipeline leakage detection and location.