多元混合工质节流制冷机逆流换热器综合传热系数的实验研究

Study On The Overall Heat Transfer Coefficient For The Countercurrent Heat Exchanger Used In Mixed-Gases Coolers

逆流换热器是多元混合工质低温节流制冷机中最为关键的部件之一,本文针对多元低温混合工质节流制冷机经常采用的管套管式逆流换热器进行实验研究,得出了采用不同工质下的换热器温度、压力沿程分布情况,并进一步得到了混合工质逆流换热器的整机换热系数。实验中各条件都是真实制冷机的典型运行工况,实验结果加深了我们对采用多元混合工质在具有相变传热情况下的工作特性的了解,对今后制冷机换热器的设计具有很大的帮助。

The countercurrent heat exchanger is one of the most important units in the mixedgases refrigeration systemAn experimental set up is established to investigate the behavior of the heat exchanger with multicomponents mixtures based on a real mixture refrigeration systemTwo tubeintube heat exchangers with different configurations are tested extensively with different mixtures operating at three typical temperature rangesThe two heat exchangers are fabricated specially to be able to measure the temperatures and pressures distributionsWith the measurement of the mixture compositions,temperatures and pressures,the thermodynamic and hydraulic behaviors of the two heat exchangers are studied extensivelyFinally,the heat transfer characteristics are obtained,which is useful in future design of the mixture refrigeration systemThe data obtained in this paper will give a good reference for future designing of such mixture throttling refrigeration system