电场作用下沸腾气泡行为实验.pdf

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化工进展
2014年第33卷第2期
CHEMICAL INDUSTRY AND ENGINEERING PROGRESS
319
研究开发
电场作用下沸腾气泡行为实验
杨侠,杨清,吴絶阳,万攀,刘丰良
(武汉工程大学机电工程学院,湖北武汉430073)
摘要:为了进一步探讨电场对沸腾传热强化机理,以水为实验工质,实验研究了电场作用下沸腾单个气泡的行
为特性。通过直接加热法产生单个沸腾气泡,并利用高速摄像机拍摄观察了不同热流密度和电场强度纽合工况
下气泡的生长过程,并对该过程中对电场作用下气池的脱离形态、周期和长径比等行为特性变化进行了相关定
性分析,根括实验结果和相关定性分析,进一步合理闻释了电水动力学强化沸腾传热机理。结果表明:外加电
场工况后,电场对沸腾气泡的脱离形态有显著的影响,气泡沿场强方向拉伸变形且场强越大,拉伸変形越明显
气泡的脱离长径比随着电场强度和热流密度的増大而变大;气泡的脱离周期随着电场强度和热流密度的増大而
减小。这表明电场和热场协同作用有助于减小气泡的停留时间来减小热源于流体之间的热阻,进一步说明电场
和热场对沸腾强化传热有一定的影响。
关键词:电场;形态;沸騰气浼;实验研究
中图分类号:TK124文献标志码
文章编号:1000-6613(2014)02-0319-05
DOl:10.39695.isSn.1000-6613.2014.02.009
Experimental study on behavior of boiling bubble in electric field
YANG Xia, YANG Oing, WU Yanyang, WAN Pan, LIU Fengliang
School of Mechanical Electrical Engineering, Wuhan Institute of Technology, Wuhan 430073, Hubci, China)
Abstract: In order to study boiling transfer enhancement mechanism, with water as working medium
the boiling bubble behavior under the influence of electric field was investigated. High-speed video
camera was used to observe the growth process of bubble produced by direct heating with different
heat flow densities and electric field intensities and the shape of escaping bubble, cycle and ratio of
length to diameter of bubble were analyzed. The experimental result and related qualitative analysis
ere used to explain EHD enhancement of boiling heat transfer mechanism. Electric ficld had a
significant effect on the behavior of bubble. The bubble was stretched along the direction of electric
field intensity. The ratio of length to diameter of bubble increased with increasing heat flow density
and electric field intensity. The cycle of bubble decreased with increasing heat flow density and electric
field intensity. Synergy of electric field and thermal field synergy helped to reduce bubble residence
time and consequently the thermal resistance between heat source and fluid, indicating the effect of
boiling heat transfer enhancement
Key words: electric field; shape; boiling bubble; experimental stud
电水动力学( electrohydrodynamics,简称EHD
是一种新型有效的强化传热技术,是通过将电场
收稿日期:2013-07-31:修改稿日期:2013-08-31。
入传热学领域,利用电场、流场、温度场场协同作
基金项目:国家白然科学基金项目(51006076,51276131)
第一作者及联系人:杨侠(1978-),男,博士,副教授,研究内容为
用以达到提高传热效率的主动强化传热技术。电场强化热技术。