economized vapor injection, calorimeter, COP, R407C
Current studies indicate that the method of economized vapor injection (EVI) increases both cooling capacity and coefficient of performance (COP) of vapor compression systems and enlarges the operating range of compressors by reducing the discharge temperature. The design and analysis of EVI systems require comprehensive and comparable performance data of the compressor. In this work, a thermodynamic model was developed to simulate the potential benefit of EVI systems. Furthermore, the performance of a vapor injection (VI) scroll compressor has been experimentally investigated using a modified compressor calorimeter and the refrigerant mixture R407C. During the experiments, the injection flow was regulated by controlling the injection superheat. The experimental results confirm the predicted tendencies of the EVI model. The investigation also reveals that the injection pressure affects the VI compressor performance and needs to be included in the compressor performance evaluation.