LNG容器蒸气膨胀爆炸特性研究

对液化天然气容器机械破损后的液体过热汽化建立了非平衡相变模型.根据非平衡相变理论,讨论了蒸气膨胀爆炸的过减压极限,并按照气泡半径是否超过临界半径,把气泡的增长分成了束缚和逃逸两个时区,分时区讨论了系统各物理量的变化.通过对液化天然气典型储运工况的计算,得出了不同条件下的过减压极限、压力下降及反弹演化过程,状态参量核化速率的变化过程及最大超压.分析了蒸气膨胀爆炸的基本特性:快速显著核化和沸腾延迟,以及初始条件、损口面积和容器尺度等对物理过程的影响.

Non-equilibrium phase-change model of BLEVE in LNG container

Aiming at Liquefied Natural Gas(LNG) superheat gasification phenomena after container broken,the non-equilibrium phase-change model has been established.According to the non-equilibrium phase-change theory,the pressure reduction limit of LNG expansion vapor explosion has been discussed.The bubble increasing is divided into the bound and escape time zone and the change of physical quantity in two time zones has also been discussed.Through the computation of typical working condition in LNG storage and transportation,the pressure reduction limit,pressure reducing and rebounding process,state parameter changing and max pressure in different conditions have been attained.Finally,the basic charaters of LNG expansion vapor explosion,such as the marked boiling and boiling delay as well as the effect of initial condition,broken area,container scale etc.on the physic process are analyzed.