LNG绕管式换热器壳侧降膜沸腾数值模拟研究

摘要使用ANSYS Fluent商用软件下的VOF模型，对天然气液化工艺中所用的绕管式换热器壳侧降膜沸腾过程进行了数值模拟。结果表明，当壳侧入口干度x ≤ 0.10时，VOF模型能较好地模拟壳侧沸腾换热现象，准确地预测出沸腾换热系数与冷剂质量流率间的关系。降膜流状态下，汽、液相流速较低，摩擦压降较小，换热管壁面基本被液膜覆盖，液相冷剂在受热壁面汽化后进入壳侧流道，流道内以汽相为主。壳侧既有竖直向下的主流运动，又有较为微弱的螺旋环流，同时大量的汽相将在壳侧顶部涡旋滞留。

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	吴志勇
	刘洋
	建伟伟
	高阳
	蔡伟华

关键词： VOF模型降膜流沸腾换热速度分布汽相体积分数

Abstract： The volume of fluid (VOF) model which attaches to the ANSYS Fluent software was employed to simulate the shell-side falling film boiling of spiral wound heat exchanger (SWHE). When inlet quality in shell-side is not more than 0.10, the shell-side boiling can be well simulated by the VOF model, and the boiling heat transfer coefficient that is related to refrigerant mass velocity may be accurately predicted. For falling film flow, the vapor velocity and the liquid velocity are so low that friction pressure drop is small. The heated wall is generally covered by the liquid film, the liquid phase will turn into the vapor phase, separate from the heated wall and enter into the flow channel of shell-side after the tube-side heat is absorbed. Besides the refrigerant flowing down which is dominant on the shell-side, the spiral flowing which is minor can be found, and the vapor eddy which stays at the top of shell-side may be identified.

Keywords： VOF model； falling film flow； boiling heat transfer； velocity distribution； vapor volume fraction

Received 2018-04-02;

Fund:工信部高科技项目（2013K4181），辽宁省博士科研启动基金指导计划项目（20170520031）。

Corresponding Authors: 吴志勇,E-mail:1123589558@qq.com。 Email: 1123589558@qq.com

About author: 吴志勇(1977-),男,博士,讲师,现从事天然气液化技术与设备方面的研究。

引用本文:

吴志勇, 刘洋, 建伟伟, 高阳, 蔡伟华.LNG绕管式换热器壳侧降膜沸腾数值模拟研究[J]. 化学工业与工程, 2019,36(3): 72-79

Wu Zhiyong, Liu Yang, Jian Weiwei, Gao Yang, Cai Weihua.Numerical Simulation of Shell-Side Falling Film Boiling of LNG Spiral Wound Heat Exchanger[J]. Chemcial Industry and Engineering, 2019,36(3): 72-79

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