Performance of Non-CFC Refrigerants for Low-Temperature Refrigeration.

As a result of the worldwide ban on chlorinated refrigerants two widely used low temperature refrigerants; R13 and R503, are being made unavailable to the refrigeration industry. As for the present, alternative refrigerants for these fluids are very limited. This paper assesses the suitability of some logically screened non-CFC refrigerants and azeotropic mixtures for low temperature cooling applications. The analysis is based on thermal-physical properties and simulated vapour compression refrigeration cycle performance of the fluids. The screening process identified two fluorocarbons (R116 and R14) and one hydrocarbon (R170) as potential non-CFC replacements. Further, the study reveals that the properties of fluorocarbon R116, mixtures R508A and R508B correlate well with those of R13 and R503. It is also found that R14 possesses desired property behaviour of a refrigerant for cooling application close to -100 °C or below, however reasonable vapour pressures, volumes and discharge temperatures need to be obtained preferably by making a blend with a second fluid.