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Blends have gained special interest recently where they can integrate the advantages of the single-fluid and may achieve excellent thermophysical properties and environmental characteristics also a better coefficient of performance. The pure refrigerant R134a commonly used in the vapor compression cycle of the cooling systems will be phased out due to its high global warming potential, while refrigerant blends of Fluorocarbon/Hydrocarbon are considered as a potential alternative owing to their excellent environmental characteristics. In this study, the thermodynamic properties and performance evaluation of the blends of (Fluorocarbon/Hydrocarbon) were investigated. In the first section, the thermodynamic properties of the refrigerant blends: R134a+R600a, R134a+R290, R1234yf+R290 and R1234ze(E)+R600a are determined with the thermodynamic model : “PR-MC-WS-NRTL” which consists of the Peng–Robinson equation of state, the Mathias–Copeman alpha function and the Wong–Sandler mixing rules requiring the NRTL model. In the second section, the performances of binary refrigerant systems as substitutes to pure refrigerant R134a in single-stage vapor compression refrigeration cycle were analyzed for the condensation temperature of 50 °C and evaporating temperatures ranging between -10 °C and 10 °C. The results presented that our thermodynamic model could describe the vapor-liquid equilibria characteristics of blends of (Fluorocarbon/Hydrocarbon), where it had the highest accuracy, with the relative deviation of 1.17 % and 0.74 % for liquid and vapor mole fractions, respectively. On another hand, the performance parameters of the refrigerant blends were analyzed where the present results showed that the performance of blend R1234yf+R290 exhibited the highest performance in terms of specific cooling capacity, coefficient of performance and environmental protection compared to other blends.

The prediction and the determination of the azeotropic point of the binary or ternary refrigerants are very important in refrigerating industry. In this task, a simple method is presented in order to predict and determine the azeotropic point. Our method employs experimental data and a thermodynamic model. trifluoroiodomethane (R13I1) in the mixture presents the possibility of inventing the azeotropic properties. The mixtures studied in this work are: binary mixtures R600a + R1234ze, R600a + R13I1, R1234ze + R13I1 and the ternary mixture R600a + R1234ze + R13I1. The model consists of the Peng–Robinson equation of state (EoS), the Mathias–Copeman alpha function and the Wong-Sandler mixing rules involving the NRTL model. The results proved that there are a good agreement between the predicted values and the experimental data. The presented methods are able to predict the azeotropic positions in binary or ternary mixture.