【摘要】 提出了用于预测混合工质脉管制冷热力学性能的改进型Brayton制冷循环 ,建立了制冷系统制冷量和制冷系数COP的理论表达式。在对多种低温流体的预测计算的基础上 ,提出了具有应用潜力的混合工质对。计算结果表明 ,如果用10 %氮与 90 %氦的混合工质对代替纯氦 ,脉管制冷机在 80K温度下的制冷系数和制冷量分别可以提高 9 5%和 6 7%。此外还讨论了其它可能用于 80K温区脉管制冷的混合工质对 ,如氢 氦、氩 氦、氖 氦混合物等。更多还原

【Abstract】 A refrigeration cycle with two isentropic and two isobaric processes referred to the modified Brayton cycle is introduced for predicting the thermodynamic performance of pulse tube refrigeration with a binary mixture refrigerant.The corresponding theoretical expressions of cooling power,thermodynamic efficiency and required work of a refrigeration cycle are established.Based on the prediction calculation of a number of cryogenic fluids,the promising mixture pairs of working refrigerants are recommended.The results computed show that 9 5% of coefficient of performance( COP )AND 6 7% of cooling power at 80 K could be gained,if a mixture pair of 10% nitrogen and 90% helium is used instead of pure helium for the pulse tube refrigeration.The minor pairs of mixture,which have positive effect for pulse tube refrigeration at temperature near 80 K including hydrogen helium,argon helium,and neon helium,are also discussed.更多还原