Numerical study of flow pattern modulation in a vertical phase separation condenser tube
Numerical study of flow pattern modulation in a vertical phase separation condenser tube
复制标题
立式相分离冷凝管流型调节的数值研究
DOI：
10.1007/s11434-013-5734-1
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发表时间：
2013-05
影响因子：
--
通讯作者：
Cao Zhen
中科院分区：
文献类型：
--
作者：
Sun Dongliang;Xu Jinliang;Chen Qicheng;Cao Zhen
提出了被动相分离的概念来调节流型以强化换热。通过流型调节，气体倾向于靠近壁面，液体倾向于管芯。通过实验验证了这一新观点，并对流型调节机理进行了定性分析。本文基于多尺度网格系统和流体体积(VOF)方法，对垂直相分离冷凝器管内单个气泡的气泡动力学进行了数值模拟，以定量探讨气泡的流型机理。结果表明：(1)调制液膜厚度比裸管区减小70%；(2)调制气泡运动速度可增加一倍，导致环状区液体速度和速度梯度增大，削弱了流体边界层；(3)环状区气泡运动速度显著增加，促进了环状区和核心区之间的质量和动量交换，产生了核心区的自持脉动流动。以上三个因素都有利于换热设备性能的提高。
The passive phase separation concept was proposed to modulate flow patterns for heat transfer enhancement. By the flow pattern modulation, the gas tends to be near the wall and the liquid tends to be in the tube core. Experiment has been performed to verify the fresh idea and the flow pattern modulation mechanism was analyzed qualitatively. This paper focuses on the numerical simulation of the bubble dynamics for a single bubble in the vertical phase separation condenser tube to quantitatively explore the flow pattern mechanism, based on a multiscale grid system and the volume-of-fluid (VOF) method. It is found that: (1) the modulated liquid film thickness can be decreased by 70% compared to that in the bare tube region; (2) the modulated bubble traveling velocity can be doubled, causing the increased liquid velocity and velocity gradient in the annular region to weaken the fluid boundary layer; (3) the significantly increased bubble traveling velocity in the annular region promotes the mass and momentum exchange between the annular region and the core region, and yields the self-sustained pulsating flow in the core region. The above three factors are benefit for the performance improvement of the heat transfer facilities.
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DOI：
10.1016/j.ijmultiphaseflow.2012.03.004
发表时间：
2012-07
影响因子：
3.8
作者：
S. Morales-Ruiz;J. Rigola;I. Rodríguez;A. Oliva
通讯作者：
S. Morales-Ruiz;J. Rigola;I. Rodríguez;A. Oliva
影响因子：
4.5
作者：
A. Miyara;Yusuke Otsubo
通讯作者：
A. Miyara;Yusuke Otsubo
DOI：
10.1016/j.ijmultiphaseflow.2012.03.007
发表时间：
2012-07-01
影响因子：
3.8
作者：
Araujo, J. D. P.;Miranda, J. M.;Campos, J. B. L. M.
通讯作者：
Campos, J. B. L. M.
影响因子：
4.1
作者：
BRACKBILL, JU;KOTHE, DB;ZEMACH, C
通讯作者：
ZEMACH, C
DOI：
10.1016/s0017-9310(98)00307-x
发表时间：
1999-06
影响因子：
5.2
作者：
D. M. Graham;J. Chato;T. Newell
通讯作者：
D. M. Graham;J. Chato;T. Newell