为了解隧道内液化天然气(LNG)管道泄漏爆炸事故的发展规律,以某实际工程为例,运用计算流体动力学方法建立隧道内LNG管道泄漏爆炸模型,分别以3种不同的边界条件对LNG泄漏爆炸过程进行了数值模拟计算。针对隧道两端为固壁和设泄压结构2种情况下的爆炸过程,通过数值模拟得到了3种不同泄漏强度条件下隧道内LNG泄漏爆炸峰值超压情况,并以此为依据判定其破坏性。结果表明,隧道两端为固壁或设泄压结构时,在泄漏强度最小及最大2种情况下爆炸形式均为爆燃,会对隧道内设施产生较严重破坏;泄漏强度居中的情况下,则会发生爆燃转爆轰过程,破坏力极强,应避免此种情况的发生。

In order to simulate the explosion process due to Liquefied Natural Gas(LNG) pipeline leakage in tunnel, a mathematical model of fire and explosion due to LNG pipeline leakage is proposed based on the Computational Fluid Dynamics (CFD) method and for an active LNG transportation pipeline in a tunnel. The LNG leakage explosion under three different LNG leakage conditions are numerically simulated, and their overpressures at the measuring points are obtained for tunnel with solid ends and pressure release ends. The explosion overpressures caused by LNG pipeline leakage under three different boundary conditions are obtained and the destruction effect is evaluated. The simulation results show that the explosion is in the form of deflagration when the LNG leakage intensity is the maximum or the minimum in the tunnel with solid ends or pressure release ends, which would damage badly the equipments in tunnel. When the LNG leakage intensity is a medium one, the deflagration would transform into the detonation with very strong damage power, and this should be avoided to be happening.