Cooling performance of several CO2/propane mixtures and glide matching with secondary heat transfer fluid

This paper presents the cooling performance of several CO2/propane mixtures measured in air-conditioning test rig at several conditions. The discharge pressure of CO2/propane mixtures is reduced with increasing mole fraction of propane and their reduced values coincide approximately with the circulation concentrations of propane. Since propane is the refrigerant having a higher refrigerating effect and a much lower vapor density than CO2, adding propane to CO2 improves the system efficiency and reduces the cooling capacity. The temperature glide effect of CO2/propane mixtures on the cooling performance was analyzed based on the experimental data. To utilize the temperature glide effect successfully, a sufficient heat exchange area is required, and the temperature gradient of refrigerant must be similar to that of secondary heat transfer fluid. It is better the temperature change of refrigerant can prevent pinching with that of the secondary heat transfer fluid.

[1]  R. N. Richardson,et al.  The performance of propane/isobutane mixtures in a vapour-compression refrigeration system , 1995 .

[2]  Piotr A. Domanski,et al.  Glide matching with binary and ternary zeotropic refrigerant mixtures Part 2. A computer simulation , 1994 .

[3]  David Didion,et al.  ROLE OF REFRIGERANT MIXTURES AS ALTERNATIVES TO CFCS. , 1990 .

[4]  Ju Hyok Kim,et al.  Vapor–liquid equilibria for the carbon dioxide + propane system over a temperature range from 253.15 to 323.15 K , 2005 .

[5]  Mo Se Kim,et al.  Performance and heat transfer characteristics of hydrocarbon refrigerants in a heat pump system , 2000 .

[6]  P. Domanski,et al.  Glide matching with binary and ternary zeotropic refrigerant mixtures Part 1. An experimental study , 1994 .

[7]  Min-Soo Kim,et al.  Cycle analysis and heat transfer characteristics of a heat pump using R22/R142b refrigerant mixtures , 1994 .

[8]  Omer Comakli,et al.  R134a and various mixtures of R22/R134a as an alternative to R22 in vapour compression heat pumps , 2004 .

[9]  Gadhiraju Venkatarathnam,et al.  Occurrence of pinch points in condensers and evaporators for zeotropic refrigerant mixtures , 1996 .

[10]  Min-Soo Kim,et al.  Circulation concentration of CO2/propane mixtures and the effect of their charge on the cooling performance in an air-conditioning system , 2007 .

[11]  Ma Yitai,et al.  The performance of some substitutes for HCFC22 under varying operating conditions , 1999 .

[12]  Mehmet Yilmaz,et al.  Performance analysis of a vapor compression heat pump using zeotropic refrigerant mixtures , 2003 .

[13]  Somchai Wongwises,et al.  Experimental investigation of hydrocarbon mixtures to replace HFC-134a in an automotive air conditioning system , 2006 .

[14]  D. Didion,et al.  Performance Evaluation of Two Azeotropic Refrigerant Mixtures of HFC-134a With R-290 (Propane) and R-600a (Isobutane) , 1994 .