Study of Refrigerant Mixtures With Gas/Liquid Injection

In this paper, the impact of gas/liquid injection on the behaviour of new alternative refrigerant mixtures such as; R-410A, R-507, R-407C, and R-404A is discussed, analysed and presented. The test results were obtained using an air-source heat pump set up with enhanced surface tubing heat exchanger under various gas/liquid injection ratios. Performance tests were conducted according to the ARI/ASHRAE Standards. During the course of this experimental study, the performance characteristics of some proposed substitutes under various gas and gas/liquid injection ratios have been investigated, analysed and compared to that with no injection. The performance data demonstrated that the effect of gas/liquid injection on mixture behaviour and the heat exchanger capacity varies from mixture to another depending upon the mixture composition, boiling point and the evaporation temperature.