小型分离式热管工作温度与传热特性的实验研究

EXPERIMENTAL STUDIES TO WORKING TEMPERATURE WITH HEAT EXCHANGING OF THE SMALL SEPARATED HEAT PIPES

本文对具有短管束的小型分离式热管工作温度与传热特性进行了实验研究。实验装置的蒸发段和冷凝段都是由5根直径20 mm的无缝钢管短管束组成,管子长度为152 mm,带有紧套的钢帛环形肋片结构尺寸如下:肋片外径40mm、厚1 mm、片间距4 mm。工作温度140-220℃,热流密度21.2-40.2 kW/m2。试验结果表明,在本实验条件下,小型分离式热管最佳充液率按蒸发段总容量计为48％-63％,按管束总容量计为20％-40％。根据实验结果,总结了最佳充液率下(25％,按管束总容量计)的蒸发段内部平均沸腾换热系数和冷凝段内部凝结换热努赛尔数综合关系式。

Some experimental studies were carried out to working temperature with heat exchanging of the small separated heat pipes with short canals. The studies were taken under the following conditions: the temperature were between 140℃ and 220℃ and the heat current was between 21.1 and 40.2 kW/m2. The diversification of αe(average boiling heat exchanging coefficient) and αc(average coagulation heat exchanging coefficient) along with the q(heat fluxion) and working temperature were measure in 6 different filling liquid ratio test conditions. According to the results of the experiments, the most optimum filling liquid ratio (which is 25%,by all capacity of pipes), and the average coefficient of boiling heat exchanging in evaporator and the synthetical equation of coefficient of heat exchanging Nusselt in condenser were developed.