R23/R134a自然复叠制冷系统研究

Study on R23/R134a Auto-Refrigerating Cascade System

对自然复叠制冷系统制冷剂选择、循环流程设计以及热力计算进行了研究,建立了R23/R134a自然复叠制冷系统实验装置。自然复叠非共沸制冷剂的沸点间距按大致等分的原则选择,一般沸点间距40～80℃。研究指出完成自然复叠制冷循环热力计算需要已知以下4个重要参数:冷凝温度、蒸发温度,以及冷凝压力、蒸发压力、浓度3个参数中的2个参数。制冷循环流程设计时,增加分凝器,可以提高低温回路制冷剂浓度;在低温回路节流阀加延时开关,可以缩短自然复叠制冷装置启动时间。R23/R134自然复叠制冷系统实验装置,最低蒸发温度达到-55℃左右,合适的R23/R134a充注浓度约在29.4%～41%之间。研究结果对自然复叠制冷系统的产品设计过程有参考价值。

The nonazeotropic mixture refrigerants selection,cycle designe and the thermodynamic performance calculation were studied,the R23/R134a ACR equipment was set up.The boiling temperature difference between the nonazeotropic mixture refrigerants of ARC is 40℃~80℃.The studies showed that the follow 4 important parameters must be known for thermodynamic calculation:condensing temperature,evaporating temperatur,,and two of the condensing pressure,evaporating pressure and concentration.The refrigeration cycle incorporated a accumulator,and lower temperature throttle delayswitch,,these improved the lower temperature loop concentration,and shorten the equipmen startup time.Experiments showed the lowest evaporating temperature was about-55℃,and the suitable concentration rang of R23/R134a mixtures was about29.4%~41%.The research results can aid the planning of the Auto-Refrigerating Cascade System products.