Modeling of an Ejector Compression Refrigerating Machine Performance Operating with Low GWP Working Fluids

A model is developed to assess the thermodynamic performance of an Ejector-Compression Refrigerating Machine (ECRM). Four Low GWP refrigerants with zero Ozone Depletion Potential (ODP) are considered: R1234yf, R152a, R290, and R717. The thermodynamic performance of the ECRM is evaluated in critical and non-critical conditions. In critical conditions, the simulation tests show that the critical pressure and critical temperature increase with the boiler temperature; and the entrainment ratio falls as the generator temperature augments. In non-critical conditions, the results reveal that there exists an optimum generator temperature and a motive ratio for which the entrainment ratio is maximum. The best entrainment ratio is achieved with R290 with the highest generator temperature and lowest motive and compression ratios, and the lowest entrainment is obtained with R717 with the highest generator temperature, motive ratio, and compression ratio.