抄録
An experimental study of the performance of a vapour compression heat pump system using a HCFC22 and CFC114 mixture of 20, 40, 60 and 100 mass% of HCFC22 as a working fluid was carried out. Heat Transfer characteristics of the condenser and the evaporator were also investigated. The condenser and the evaporator were counter flow heat exchangers with a smooth copper tube of 12 mmID and 8 m length. The experiments were performed under the conditions that the flow rates of the heat source and sink water and their inlet temperatures of the heat exchangers were kept constant, maintaining the constant evaporating temperature at the inlet of the evaporater. The results indicate that the coefficients of performance (COP) in case of the mixtures are about 45% higher than that of pure HCFC22 in the range of CFC1l4 mass fraction from 0.6 to 0.8 and the effect of the composition of mixtures on COP is well agreement with that obtained from the thermodynamic cycle analysis. Overall heat transfer coefficient of mixtures decreases with increasing CFC114 mass fraction of the mixture and the empirical correlation for the effect of the composion of the mixture on condensation heat transfer is obtained.
