微槽强化管内的流动沸腾传热特性

Flow Boiling Heat Transfer Characteristics of Liquid Through Microchanneled Enhanced Tubes

本文对所开发的两种微槽沸腾相变传热管进行了流动沸腾实验研究,考察了强化管对沸腾传热的强化效果和传热性能。实验结果表明,这种结构简单、加工方便、易于应用的强化技术可有效地提高沸腾传热,使核沸腾传热所需的壁面过热度比光管要低得多,EH比SM管低4～5C以上,EC比SM管低10C以上,临界热负荷也显著提高,增强了临界热负荷区的运行稳定性。

Two kinds of circular tubes with microchannels on the inner wall were developed for enhancing inside flow boiling heat transfer. The boiling characteristics of liquid through these tubes was investigated experimentally. Their heat transfer performance was also compared with that of smooth tube. The experimental results show that these tubes effectively improvie flow nucleate boiling behavior and augment the heat transfer. The wall superheat for the nucleate boiling is much lower than that of smooth tube, about 4~5C or more lower for EH tube and 10 C or more lower for EC. The critical heat flux (CHF) is obviously increased. From the experiments, it was found that the better stability of operation hear the critical heat flux or transition regime was reached for the enhanced tubes. The most attractive feature is that their simple configuration smakes these tubes easy to fabricate and convenient to use in practical applications.