摘要
以水和三种不同质量分数(0.2%、0.5%和1.0%)的Al2O3纳米流体作为实验工质,在三种不同尺寸微槽道中进行饱和沸腾传热实验,研究沸腾传热过程中临界热流密度(Critical Heat Flux,简称CHF)的变化特性。主要分析了微通道水力半径、纳米流体浓度、进口过冷度和临界热力学干度等因素对CHF的影响。实验结果发现:在水力半径较小的槽道内CHF发生得比较早;CHF随纳米流体浓度的增大而增大;CHF随进口过冷度增大有细微增大的趋势;CHF随临界热力学干度的增大而减小。文中还将实验结果与现有的、工况条件与本实验相近的理论模型进行了拟合比较,发现理论模型能较好预测本实验。
With the working fluids being water and nano - fluids of three different kinds of mass fraction （0.2% , 0.5% and 1.0% ） , experiments were carried out in microchannels of three different sizes to study the variation characteristics of the CHF during the boiling heat transfer process. The paper mainly focused on the effect on the critical heat flux （CHF） of the impact factur, such as microchannel hydraulic radius, nanofluid concentration, import subcooling and critical thermodynamics dryness. Results show that the smaller the hydraulic radius is, the earlier the CHF happens; the CHF has an increasing intendensy when the mass fraction increases; the CHF increases slightly with the increasing of the import subcooling; and the CHF decreases with the increasing of the critical thermodynamics dryness. The paper compared the experiment results with existing theory model whose working condition was similar to the experiment. Results show that theory model can well predict the experiment.
出处
《低温与超导》
CAS
北大核心
2013年第6期75-80,共6页
Cryogenics and Superconductivity
基金
国家自然科学基金资助项目"基于低表面能处理的微细通道电场强化纳米流体相变传热研究"(21276090)
