摘要
通过分析回热器对R290/CO2、NH3/CO2、R404A/CO2三种复叠式制冷系统性能的影响,得出在一定的冷凝温度、蒸发温度和冷凝蒸发器传热温差下,回热循环能提高R290/CO2、R404A/CO2复叠式制冷系统的性能系数,且当回热器效率大于0.31时,R290/CO2复叠式制冷系统的性能系数超过NH3/CO2复叠式制冷系统的性能系数,减少R290/CO2、NH3/CO2、R404A/CO2复叠式制冷系统中高温循环制冷剂的充注量,从而提高复叠式制冷系统的安全性。
The effects of liquid-suction heat exchanger on the performance of three kinds cascade refrig- eration system, namely R290/CO2 , NH3/CO2 and R404A/CO2 , were analyzed. It is found that, at a defi- nite condensing, evaporating temperature and heat-transfer temperature difference of condensation-evapora- tor,the coefficient of performances （COP） of R290/C02 and R404A/CO2 cascade refrigeration system in- creases by using liquid-suction heat exchanger. The COP of R290/C02 cascade refrigeration system is larger than that of NH3/CO2 when the effectiveness of liquid-suction heat exchanger is higher than 0.31. Reducing the refrigerant charges in high temperature cycle of R290/C02 , NH3/CO2 and R404A/CO2 can improve the security of cascade refrigeration system to some extent.
出处
《低温工程》
CAS
CSCD
北大核心
2014年第2期60-63,76,共5页
Cryogenics
关键词
回热器
过热度
复叠式制冷系统
liquid-suction heat exchanger
degree of superheat
cascade refrigeration system
