低温气瓶气相区温度分布研究

Study on temperature distribution in the gas phase of cryogenic vessels

低温绝热气瓶储存低温液体,当气瓶处于额定充满率时,气瓶内部温度一般处于储存液体的饱和温度,但充满率降低时,由于气液两相物性参数的差异,其气相区温度分布会呈现出较液相明显的分层现象。为研究环境温度和充满率对低温绝热气瓶内部气相空间温度分布规律的影响,开展了实验和数值模拟研究,利用搭建的恒温箱,选取2种不同规格的气瓶,对不同恒温箱温度和充满率下的气瓶内部气相空间温度分布进行了实验研究。实验结果表明:恒温箱温度不变而充满率变化时,随着充满率的升高,气相区温度分层趋势加剧;而充满率不变时,恒温箱温度对气相区温度分布的影响较小。另外,对气瓶内壁面温度进行了数值模拟,模拟结果显示,壁面温度分布规律与气相温度分布规律具有一致性,同一高度处内壁面温度高于气相温度,对气相区内壁面温度取算术平均值时,充满率越低,其值越大。

When the cryogenic vessels is at the rated filling level,the internal temperature of the gas cylinder is generally at the saturation temperature of the stored liquid,but when the filling level decreases,due to the difference in the physical properties of the gas/liquid,the distribution of the temperature of the gas phase will show more obvious stratification than the liquid phase.In order to study the influence of ambient temperature and filling level on the temperature distribution of the gas phase space inside the cryogenic vessels,this paper studies it by means of experiment and numerical simulation.Using the thermostat chamber,two different specifications of vessels are selected to conduct an experimental study on the temperature distribution of the gas phase space inside the vessels at different temperatures and filling level.The experimental results show that when the temperature of the thermostat chamber is constant and the filling level changes,as the filling level increases,the temperature stratification trend of the gas phase zone intensifies.The temperature has little effect on the temperature distribution in the gas phase.In addition,the numerical simulation of the inner wall temperature of the vessel is carried out in this paper.The simulation results show that the wall temperature distribution is consistent with the gas phase temperature distribution.The temperature of the inner wall surface at the same height is higher than that of the gas phase.At the average value,the lower the filling level,the larger the average temperature of the inner wall.