High pressure buried gas pipeline leakage temperature drop testing and theory analysis

Abstract

Great damages to environment will be caused once high pressure buried pipeline leakage leaks occurs. Distributed temperature sensing (DTS) is a good monitoring method of temperature change. Gas from buried pipe leaks is monitored by changes caused by the Joule-Thomson (J-T) effect. In this work, the temperature variation of buried pipeline leakage is analyzed by finite element method (FEM). The temperature drop of nitrogen at the leak hole is calculated by using the J-T empirical formula. In addition, the site test of buried high pressure nitrogen pipeline leakage is carried out. The results show that the temperature drop the leakage hole is obvious, and the temperature directly above the leakage hole decreases with the increase of the distance from the leakage hole. The larger leakage pressure, the greater the temperature drop. Therefore, the fiber needs to be placed closer to the pipeline to monitor the soil temperature change.