大型LNG储罐分层破坏及翻滚过程的数值研究

建立了大型LNG储罐分层及翻滚模型,充分考虑了LNG多组分、变物性的特点,分别研究了分层破坏的机理及分层温差、分层高度、漏热量和漏热位置对翻滚剧烈程度的影响。结果表明:当底部漏热为10 W/m~2,上下层温差大于0.2 K时会发生翻滚,且温差越大,翻滚发生越容易,翻滚程度越剧烈。当底部漏热10 W/m~2,上下层高度越接近时,翻滚程度越剧烈。无论是底部漏热还是侧壁漏热,漏热量越大时,翻滚程度越剧烈。漏热量相同时,侧壁漏热发生翻滚的时间要早于底部漏热,但剧烈程度要小于底部漏热。

Numerical simulation of destratification and rolling process in large LNG storage tank

The mechanism of destratification and rollover in large LNG storage tank is studied.The model of stratification and rollover in large LNG storage tank was presented.Meanwhile,the characteristics of the LNG multicomponent and variable physical properties were taken into consideration.The mechanism of destratification,the influences of temperature difference and height of stratification layers,heat leakage and leakage location on rollover were studied.The results show that when heat leakage at the bottom wall was 10 W/m2 and the temperature difference of stratification layers was greater than 0.2 K,the rollover occurs.Furthermore,the intensity of the rollover increaseds with the increasing temperature difference.Moreover,when heat leakage at the bottom wall reaches 10 W/m2,the intensity of the rollover increases with the height decreasing difference of stratification layers.Whether heat leakage occure at the bottom wall or the side wall,the intensity of the rollover increases with the heat leakage.Furthermore,when heat leakage at the bottom wall is the same as that at the side wall,the occurrence of the rollover caused by the side wall heat leakage was earlier than that by the bottom wall heat leakage,but the intensity of the rollover caused by the side wall heat leakage was smaller than that at by the bottom heat leakage.