一种替代三级复叠式制冷系统的方案分析

An Alternative Solution Analysis of Three Cycle Cascade Refrigeration System

以提高-120℃^-80℃温度区间内运行的制冷系统能效为目标,对采用R1150/R41/R717的制冷剂组的三级复叠式制冷系统进行分析,提出采用R1150/R717制冷剂组的双级压缩复叠式制冷系统的替代方案,对系统的排气温度、压缩机输入功率、COP、热力学完善度、?效率、?损失及部件?损失所占比例进行理论分析。研究结果表明:在-120℃^-80℃蒸发温度范围内,双级压缩复叠式制冷系统的压缩输入功率比三级复叠制冷系统的压缩功低1.3 kW^3 kW。双级压缩复叠式制冷系统COP和热力学完善度比三级复叠式制冷系统COP高约12.8%~14.7%。双级压缩复叠式制冷循环的?效率大于三级复叠式制冷系统的?效率,双级压缩复叠式制冷循环的?损失小于三级复叠式制冷系统的?损失。综上所述,在-120℃^-80℃蒸发温度范围内,采用双级压缩复叠式制冷系统替代三级复叠制冷系统的技术方案是可行的。

In order to improve the energy efficiency of the refrigeration system,operating in the evaporation temperature range of-120℃^-80℃,this paper analyzes the three cycle cascade refrigeration system(TCRS)using refrigerant group of R1150/R41/R717 and proposes an alternative solution of cascade refrigeration system with two-stage compression(CRST)using the refrigerant group of R1150/R717.And it analyzes the discharge temperature of compressor,input power of compressor,COP,Thermodynamic perfect degree,exergy efficiency,exergy loss and percentage of exergy loss in each process.The results show that the input power of compressor of CRST is lower than that of TCRS in value of 1.3 kW^3 kW in the refrigeration temperature range of-120℃^-80℃.The COP and thermodynamic perfect degree of CRST is higher than that of TCRS with 12.8%~14.7%.The exergy efficiency of CRST is higher than that of TCRS,while the exergy loss of CRST is lower than that of TCRS.In summary,adopting the CRST as the alternative solution of TCRS is feasible.