本文通过理论计算对CO2/DME混合制冷剂替代CO2的跨临界制冷循环特性进行了分析,结果表明:CO2/DME混合制冷剂的质量配比范围为90/10~100/0时,可实现混合制冷剂的直接充灌。在相同的工况下,CO2/DME跨临界制冷循环的最优高压侧压力降低了3 MPa,制冷系数提高4.3%;过热度对循环性能的影响,纯质CO2要大于混合工质CO2/DME。
The performance of a transcritical refrigeration cycle with an alternative refrigerant CO2/DME for CO2 is theoretically analyzed and calculated. The results indicated that the mixture refrigerant CO2/DME is filled directly without changing a refrigeration system with a mass fraction of DME ranging from 0% to 10%. In the similar conditions, the CO2/DME lowers the discharge pressures by about 3 MPa, and the coefficient of performance (COP) is increased by about 4.3 percent. The influence of superheat on a pure refrigerant CO2 is larger than that of the mixture refrigerant CO2/DME.