摘要
本研究在工质水中布置针状电极,研究非均匀电场对其池沸腾换热过程中传热系数以及临界热流密度的影响,同时测量了不同电压下沸腾表面接触角的变化,以及可视化的观察到了气泡的产生以及脱离相对于无电场情况下的变化。结果表明,在低热流密度区电场强化传热,且强化效果随热流密度的增加而减弱。在中热流密度区电场恶化传热,恶化效果随着热流密度的增加先增加后减弱。而在高热流密度区电场强化传热,且随着热流密度的增加强化作用减弱。由于施加电场改善了沸腾表面润湿性、增加了活化核心点数目且将部分大气泡击碎成小气泡,从而传热强化。根据本文实验结果,基于电场下池沸腾基本模型,提出了预测电场下传热系数变化模型,且预测效果较好。
In this study, needle electrodes were arranged in working medium water to study the influence of non-uniform electric field on the heat transfer coefficient and critical heat flux in the pool boiling heat transfer process. Meanwhile, the boiling surface contact angle was measured at different voltage, and the change of bubble generation and detachment relative to the condition without electric field was observed through visualization method. The results show that the heat transfer is enhanced by electric field in the low heat flux, and the strengthening effect is gradually weakened with the increase of heat flux. In the middle heat flux, the heat transfer is deteriorated by electric field, and the worsening effect increases first and then decreases with the increase of heat flux. In the high heat flux, the heat transfer is improved by electric field, and the strengthening effect weakens with the increase of the heat flux. Because the electric field improves the wettability of the boiling surface, increases the number of activated core points and breaks part of the large bubbles into small bubbles. Thus, the heat transfer is enhanced. According to the experimental results in this paper, a revised model based on the basic pool boiling model under electric field to predict the change of heat transfer coefficient under electric field is proposed, and the prediction results are good.
作者
郭俊
李双菲
陈彦君
刘修良
贺德强
GUO Jun;LI Shuang-Fei;CHEN Yan-Jun;LIU Xiu-Liang;HE De-Qiang(Guangxi Key Laboratory of Manufacturing System and Advanced Manufacturing Technology,School of Mechanical Engineering,Guangxi University,Nanning 530004,China;Shanghai Aerospace System Research Institute,Shanghai 201108,China;School of Power and Energy Engineering,Huazhong University of Science and Technology,Wuhan 430074,China)
出处
《工程热物理学报》
EI
CAS
CSCD
北大核心
2022年第3期788-796,共9页
Journal of Engineering Thermophysics
基金
国家自然科学基金资助项目(No.51806155)
广西自然科学基金面上项目(No.2019GXNSFAA245038)。
关键词
电场
沸腾换热
气泡
接触角
预测模型
electric field
boiling heat transfer
bubble
contact angle
predicted model
