Numerical study on the horizontal stretching effect of ground on high-pressure vapor jets of LNG tank leakage

• Published in: Journal of loss prevention in the process industries 2021-09, Vol.72, p.104526, Article 104526
• Main Authors: Xie, Qiyuan, Lu, Qizhao, Yuan, Yanhua, Zhang, Jie, Zhou, Feng
• Format: Article
• Language: English
• Subjects: Boundary layer; Height of the orifice; High-pressure vapor jet; Horizontal stretching; LNG tank leakage
• ISSN: 0950-4230
• DOI: 10.1016/j.jlp.2021.104526

The objective of this work is to investigate the horizontal stretching effect of ground on high-pressure vapor jet of LNG tank leakage near the ground. A numerical model for leakage jet was developed and several series of leakage scenarios were theoretically analyzed for different heights of the tank orifice, inner pressures and outer temperatures. The results show that the near ground plays an important role in the horizontal transportation of LNG leakage vapor. The corresponding danger distance is surprisingly lengthened because of the horizontal stretching of leakage vapor cloud by the ground nearby, especially for those cases with a lower orifice on tank. It is illustrated that there is an obvious change for the central axis track, gas concentration and velocity of the jet in the far-field during the jet is touching the ground. In addition, the dimensionless analyses on the dependence of gas concentration, velocity and gas concentration on the transportation distance indicated that there were two stages of deflection behaviors of the jet. Finally, the enlarged danger distance by the horizontal stretching for the LNG tank leakage with a low orifice indicated the more dangerous scene of those leakage close on ground. The data and revelation here about the danger area prediction can be an important guide for the emergency management during the LNG tank leakage accidents. •Leakage and transportation model for LNG tank leakage with a small orifice is developed.•Near ground plays an important role in transportation of LNG high-pressure leakage jet.•Danger area of LNG leakage is obviously enlarged by horizontal stretching of ground.•Dimensionless parameters of LNG jet transportation suggest two stages of deflections.•The scene of LNG leakage with a low orifice needs more attention in emergency management.