低温绝热气瓶真空丧失后内容器热流场分析

Thermal flow field analysis of liquid in a vacuum-loss cryogenic cylinder

建立了真空丧失后低温液体在金属表面上的核态沸腾模型,并用于计算液氮充满率为90%的175 L立式低温绝热气瓶真空丧失后容器内的液体流动、传热及沸腾过程。研究表明,真空丧失后液体温度出现明显分层,且温度分层的方向会随着时间的增加而发生变化;容器内液体在整个容器内形成环状自然循环,而沸腾产生的汽泡主要集中在近壁区和气液界面。

Nucleate boiling model of cryogenic liquid on the surface of metal was proposed at the condition of vacuum loss. The model was used to calculate the fluid and heat transfer procedure of cryogenic liquid evaporating in the cylinder with volume 175 liters and block coefficient 90%. The result illustrates that the temperature of liquid in the cylinder appeared obviously lamination after vacuum loss and the orientation of lamination changes with time. Cryogenic liquid formed natural circuit in the whole cylinder. Bubbles of evaporation mainly focused on the area near the metal wall and the interface of liquid and gas.