摘要
针对在不同环境温度和大气风速条件下,液化天然气(LNG)船舶在发生水下泄漏时,泄漏出的LNG液体的传质与传热问题,基于计算流体力学软件FLUENT,采用VOF法并编程定义传质与传热源项对水下泄漏问题进行了仿真研究.通过仿真数值计算,得出LNG发生水下泄漏时,流场温度场、粘度场和海域结冰情况,计算了LNG和低温气体由于沸腾反应质量随时间的变化规律,探讨了LNG水下排放传质与传热机理.结果表明,海域中温度较高的区域仍有低温LNG存在,但由于LNG快速相变对海水的强烈扰动,不利于海水凝固成冰;当未沸腾的LNG浮到海面上时,在海面会有冰层形成;环境温度越高、风速越大,LNG沸腾产生的NG量越多,海域结冰量越少.
The heat and mass transfer between liquefied natural gas （LNG） and the environment caused by an LNG vessel leakage underwater was simulated using FLUENT software under different conditions of environment temperature and wind velocity. The VOFwas used to define heat and mass source terms, and an experimental average heat exchange velocity value was applied to the environment of the leak. Through numerical simulations, the authors derived distributions of flow, temperature, viscosity, and ice forming mechanisms. A rule was derived for LNG and NG mass changes with time due to boiling. Mechanisms for heat and mass transfer in an LNG vessel＇s underwater leakage were discussed. On that basis a formula for the effect of environmental temperature and wind velocity on the simulation was proposed. The results show that in high temperature seas there will still be low temperature LNG, but because of violent motion caused by the LNG＇s rapid phase change, the formation of ice is difficult. When unboiling LNG reaches the surface of the sea, phase change then forms ice. The higher the environmental temperature and wind velocity, the greater the quantity of heat and mass transferred, the lower the quantity of ice formed.
出处
《哈尔滨工程大学学报》
EI
CAS
CSCD
北大核心
2009年第8期855-859,共5页
Journal of Harbin Engineering University
基金
中国交通部深圳海事局基金资助项目(9005108)
关键词
液化天然气船舶
水下泄漏
温度
风速
热传导速率
LNG vessel
leakage underwater
temperature
wind velocity
heat transfer velocity
