丙酮污染对微型机械制冷机性能影响的实验研究

设计微型高压阀直接向机械制冷机内在线、连续地添加污染杂质,提出了制冷机丙酮污染的强化加速实验方案,从量化角度深入研究了污染对回热式机械制冷机性能影响的规律.实验分析表明,随着丙酮添加量的增加,制冷能力首先稍微增强,然后在42 mg和121 mg时分别出现了性能衰变的拐点.在间歇性开机时还发现了制冷机污染效应的时延现象.结合传热、流阻等理论对实验规律进行了分析讨论,为机械制冷机的可靠性技术和寿命预测研究奠定了基础.

Experimental research on the effect of acetone contamination on miniature mechanical cryocooler performance

A novel high pressure microvalve was designed by which the contamination could be injected on-line into the running cryocooler continuously. The accelerated acetone contamination experimental method was proposed in order to investigate quantificationally the effect of contamination on the performance of mechanical cryocooler. The experiments show that with the quantity of injecting acetone increased, the cooler performance would enhance a little, and then two critical degradation points occur at 42 mg and 121 mg respectively. The time-delay rule of contamination effect was also discovered during the cooler discontinuous operation. The relationship of performance degradation with acetone contamination was analyzed theoretically based on the heat transfer and fluid resistance mechanism, which will lay a foundation of the research on reliability and life-time estimation of cryocooler.