CO_2蒸气固体颗粒制冷系统

New Refrigeration System Using Vapor-Solid CO_2 as Refrigerant

压缩式制冷装置通常利用液体汽化吸热来获得冷量,由于CO2在三相点-56℃以下时产生固体,故不能用它作为制冷剂来获得-56℃以下的低温环境.提出一种利用CO2蒸气固体颗粒作为制冷剂的制冷系统,可以以CO2为工质获得三相点以下的温度.在该系统中,采用可调喷嘴、升华器、高、低压流量调节阀代替原系统中的蒸发器,并对该系统进行了理论循环分析.结果表明,理想情况下该系统COP比现有的制冷系统高约50%.

CO2 can not be used as refrigerant in vapor-compression refrigeration system for temperature lower than --56 ℃, because refrigerant must be in liquid phase in vapor-compression refrigeration system, and solid CO2 will form under the triple point temperature -56 ℃. This paper put forward a refrigeration system with CO2 vapor-solid particles as refrigerant, by which the temperature lower than the triple point is achieved. In this system, an adjustable nozzle, sublimator, high-pressure regulating valve and low-pressure regulating valve are used to replace the conventional evaporator. The theoretical cycle analysis of the refrigeration system shows that its COP is about 50% higher than that of the conventional one.