Effects of millimetric geometric features on dropwise condensation under different vapor conditions
Effects of millimetric geometric features on dropwise condensation under different vapor conditions
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DOI：
10.1016/j.ijheatmasstransfer.2017.11.139
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发表时间：
2018-04
影响因子：
5.2
通讯作者：
Yajing Zhao;D. J. Preston;Zhengmao Lu;Lenan Zhang;John Queeney;E. Wang
中科院分区：
文献类型：
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作者：
Yajing Zhao;D. J. Preston;Zhengmao Lu;Lenan Zhang;John Queeney;E. Wang
在这项工作中，我们研究了两种不同的环境下：纯蒸汽和空气-蒸汽混合物的毫米表面结构对滴状冷凝传热的影响。我们的实验结果表明，虽然凸形结构，使更快的液滴增长的空气-蒸汽混合物，相同的结构施加在纯蒸汽冷凝的相反效果，阻碍液滴的增长。我们为每种情况开发了一个模型来预测沿着结构化表面沿着的热流分布，并且该模型与实验结果显示出合理的一致性。这项工作表明，滴状冷凝的几何特征的影响是不是不变的，而是依赖于在系统中的传热和传质阻力的情况。在这项研究中开发的基本理解冷凝应用，包括发电，海水淡化，露水收集和热管理提供了有用的指导方针。
In this work, we investigated the effects of millimetric surface structures on dropwise condensation heat transfer under two different environments: pure vapor and an air-vapor mixture. Our experimental results show that, although convex structures enable faster droplet growth in an air-vapor mixture, the same structures impose the opposite effect during pure vapor condensation, hindering droplet growth. We developed a model for each case to predict the heat flux distribution along the structured surface, and the model shows reasonable agreement with experimental results. This work demonstrates that the effects of geometric features on dropwise condensation are not invariable but rather dependent on the scenario of resistances to heat and mass transfer in the system. The fundamental understanding developed in this study provides useful guidelines for condensation applications including power generation, desalination, dew harvesting, and thermal management.