跨临界CO_(2)两级压缩直冷制冰系统热力学性能研究

Thermodynamic Performance of Transcritical CO_(2) Two-stage Compression Direct Cooling Ice Making System with Complete Inter-cooling

为降低CO_(2)制冰系统能耗,提高系统性能,提出了双级压缩中间完全冷却引射膨胀直冷制冰系统(TCEIS)。通过构建热力学模型,分析了关键参数对系统性能的影响,在此基础上对TCEIS应用于不同季节和城市的COP R+HR、年耗电量和热回收量及年运行费用和热回收收益进行了研究,并与双级压缩直冷制冰系统(TCS)、双级压缩中间完全冷却直冷制冰系统(TCIS)和单级压缩引射膨胀直冷制冰系统(ES)进行对比。结果表明:在考虑热回收的情况下,TCEIS具有最高的COP R+HR,且在越炎热的季节和城市优势越明显。TCEIS在广州运行时,在分别满足冬季(410.989 kW)、过渡季(542.092 kW)和夏季(701.353 kW)制冷负荷的需求下,年运行成本相较于TCIS、TCS和ES可分别减少10.76万元、39.79万元和58.31万元。可为CO_(2)直冷制冰系统的构建和应用提供理论参考。

To reduce the energy consumption of a CO_(2) ice-making system and improve system performance,this study proposes a transcritical CO_(2) two-stage compression ejector expansion direct cooling ice-making system with complete intercooling(TCEIS).The effects of key parameters on system performance were analyzed by developing a thermodynamic model.Using this model,the COP R+HR,annual power consumption,heat recovery capacity,annual operating cost,and heat recovery income of the system applied in different seasons and cities were evaluated and compared with those of a two-stage compression direct cooling ice-making system(TCS),a two-stage compression direct cooling ice-making system with complete intercooling(TCIS),and an ejector expansion direct cooling ice-making system(ES).The results show that TCEIS has the highest COP R+HR considering heat recovery,with the advantages being noticeable in hot seasons and cities.When operating in Guangzhou with cooling loads of 410.989 kW in winter,542.092 kW in transition seasons,and 701.353 kW in summer,the annual operation cost of TCEIS can be reduced by 107.6 thousand yuan,397.9 thousand yuan,and 583.1 thousand yuan compared with those of TCIS,TCS,and ES,respectively.This study provides a theoretical reference for the construction and application of CO_(2) direct-cooling ice-making systems.