摘要
研究了一种NH3/CO2 复叠式低温制冷系统 ,其中高温部分采用NH3做工质 ,低温部分利用CO2 为工质 .通过对NH3/CO2 复叠式制冷系统的性能进行的热力学模拟计算 ,分析了该循环的运行参数和性能系数在中间温度和冷凝温度改变时的变化规律 ,结果表明 :在同一冷凝温度下 ,复叠式两级低温制冷系统存在一个最佳中间温度 ,使系统性能系数最大 ,在最佳中间温度的± 5K范围内 ,性能系数降低很少 ;高温级冷凝温度改变时 ,循环性能系数也要随之变化 ,随冷凝温度增加 ,系统达到最大性能系数时的最大中间温度也增加 .
Studied is a kind of ammonia/carbon dioxide two stage low temperature refrigeration system, in which ammonia is used as the refrigerant in the high temperature stage and carbon dioxide is used as the refrigerant in the low temperature stage. The performance of the system is simulated and analyzed by changing the mean temperature of the evaporator condenser and the temperature of the condenser. The mean temperatures of the evaporator condenser are calculated to maximize the coefficient of performance(COP) of the system at different condensing temperatures. It is shown that there exists an optimum mean temperature in evaporator condenser to maximize the COP of the system, and the maximal COP of the system is increased with lowering the condensing temperature. The relationship between the optimum mean temperature and the condensing temperature is given.
出处
《西安交通大学学报》
EI
CAS
CSCD
北大核心
2002年第5期526-540,共15页
Journal of Xi'an Jiaotong University
基金
国家自然科学基金资助项目(5 980 6 0 10 )
关键词
二氧化碳
氨
制冷系统
天然工质
carbon dioxide
ammonia
refrigeration system
natural refrigerant
