学术
摘 要:
实验研究了矩形液池中蒸发薄液层中蒸发效应与热毛细对流的耦合机理．对于单纯的热毛细对流稳定性从实验和理论上已有深入研究，但目前国际上对带有蒸发界面的热毛细对流问题尚缺乏研究．特别是近来的研究发现，气液界面的蒸发对热毛细对流稳定性有很大的影响．本实验以温度为主要控制参数，测量了不同工况下蒸发界面不同点的蒸发速率和表层温度，并利用PIV方法分析得到了液体内的流场分布．实验结果发现，随着沿界面的温差增加，蒸发液体内的流型从稳定的单涡胞结构变为稳定的多涡胞结构，并最终演变为紊流结构．综合分析以上测量结果并与理论分析结果进行了比较．[著者文摘]
文章出处:
《空间科学学报》-2008年1期 -12-16页
分 类 号:
Experimental Study on the Coupling of Thermocapillary Convection and Evaporation Effect in a Liquid Layer
ZHU Zhiqiang JI Yan LIU Qiusheng YAN Jiaping XIE Jingchang （Institute of Mechanics, Chinese Academy of Sciences, Beijing 100080）
Abstract:
There has been a variety of applications for thermocapillary convection and evaporation, such as thin-film evaporators, boiling technologies and heat pipes. And the stabilities of thermocapillary convection in a fluid layer subjected to a horizontal temperature gradient have been experimentally and numerically analyzed by many scientists. While the interfacial flow with evaporation, which is a classical physical phenomenon, is absent of comprehensive understanding. Recently, many theoretical and experimental researches have found that evaporation plays a very important role in the instabilities of thermocapilllary convection. In our experiment, we study the coupling of theromcapillary convection and evaporation effect for 0.65 cst Silicone Oil as the experimental liquid in a rectangular cavity which has the length of 0.08 m and width of 0.04 m. The temperature gradient along the liquid layer, which induces the thermocapillary convection, is the dominate parameter. The temperature at the interface and the evaporating rate are measured by a thermocouple and a laser cofocal displacement meter, respectively. The PIV method is applied for flow visualization, and the flow pattern transforms from a steady unicellular flow to a steady multicellular flow, to a turbulent flow ultimately with the temperature difference along the interface increases from 2℃to 14℃. For discussion, the experimental results are compared with linear stability analysis.[著者文摘]
Key words:
Thermocapillary convection, Buoyancy convection, Evaporation, Fluid experiment,PIV method
基金资助:
国家自然科学基金项目（10772185,10372105）和中国科学院知识创新工程（KGCX-SW-409）共同资助
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