Simulation of the Performance of Alternative Refrigerants in Liquid Chillers

The impact of man-made chemicals on the environment, and in particular, the ozone layer, has been investigated over the last 20 years. The phaseout of CFCs under European Regulations and the Montreal Protocol has already taken place and HCFCs are set to follow. A wide range of alternative refrigerants with zero ozone depletion potential have already been developed as replacements for the refrigeration industry. Mathematical modelling of refrigeration systems enables the performance of these alternatives to be evaluated across a broad range of operating conditions. This paper investigates the simulated performance of a liquid chiller retrofitted with a range of alternative refrigerants. The mathematical model of the system is briefly outlined and the properties of the alternative refrigerants discussed. The performance of the system is determined in terms of cooling capacity, power consumption and coefficient of performance for a range of different operating conditions. The relative performance of each refrigerant is discussed and the preferred alternative identified for typical applications.