Experimental Research on Leakage and Diffusion Characteristics and Leakage Quantity Prediction of Underwater Gas Pipeline

• Published in: 淡江理工學刊 Vol. 23; no. 1; pp. 143 - 152
• Main Authors: Shaoxiong Wang, Yuxing Li, Cuiwei Liu, Zhaoxue Cui
• Format: Journal Article
• Language: English
• Published: 淡江大學 01.01.2020
• Subjects: Leakage; Flow Rate; Bubble Plume; Diffusion Law; Underwater Pipelines
• ISSN: 2708-9967
• DOI: 10.6180/jase.202003_23(1).0015

The leak experiment for underwater gas leakage was carried out by using self-designed circular pipeline and air as experimental medium. The diffusion characteristics of gas in water and the variation of flow rate as a function of different water depth, hole diameter and leakage pressure were studied. The results show that the bubble plume has experienced three stages after the leakage: the initial stage, the full development stage and the surface flow stage. During the rise of the bubble plume, the phenomenon of entrainment, necking and recoil are accompanied. The leakage rate has a linear relation, second order relation with the leakage pressure and diameter of hole respectively, while it decreases with the increase of water depth. The change of the hole diameter has the greatest influence on the leakage rate, followed by the pressure, while the effect of water depth is the smallest. The nonlinear fitting of the experimental data is carried out to obtain the quantitative relationship between the release flow rate and the hole diameter, leakage pressure and water depth. At the same time, by introducing coefficient α, a quantitative formula for predicting the leakage rate of underwater gas pipelines under the conditions of small hole diameter (d ≤ 20 mm) and subsonic flow (p ≤ 90 kPa) is obtained.