氯化钠水溶液管外沸腾换热的模拟实验研究

Analog Experiment Research of Boiling Heat Transfer of Polished and Screwed Tube

基于传热学实验研究的相似理论 ,对溴化锂吸收式制冷机高压发生器中常用的光管和外螺纹管的沸腾换热过程用氯化钠水溶液进行了模拟实验研究 ,得到了管壁面过热温度为 2～ 7℃和热流密度为 1～ 2 0kW·m-2下 ,光管和外螺纹管核态沸腾对流换热的实验数据 (包括在纯水、不同质量分数的氯化钠水溶液、单管光管、三管光管、单管螺纹管和三管螺纹管之间八种组合的沸腾热换工况 ) .通过将实验结果进行数据处理 ,并与溴化锂溶液沸腾换热工况的数据进行相似性比较和分析以后发现 ,结果吻合良好 .由此可知 ,通过调整和扩大模拟实验的范围 ,可以得到大量的模拟实验数据 .将这些实验数据稍作修整即可直接应用于溴化锂吸收式制冷机换热设计计算或校核计算过程 .

In this paper,based on the analog theory of experiment research of heat transfer,we made analog experiment research of boiling heat transfer for polished tube and screwed tube which are widely used in the high pressure generator of lithium bromide absorption refrigerator.From the experiment research,we got a series of results of boiling heat transfer of single tube and three tubes which are polished and screwed respectively,and the working condition is near the zone of bubble boiling and the wall overheat temperature ranges from 2 to 7℃,heat flux q from 1 000 to 20 000 W·m -2 ,with the fluid medium of pure water and salt water solution.These results well agree with the known results,and are applicable for the practical design of the high pressure generator of lithium bromide absorption refrigerator.