Experimental Study of Ejector Integrated in Vapor Compression Refrigeration Systems Utilizing Low-Grade Heat Sources

An air-conditioning system utilizing an ejector offers several advantages, including compactness, cost-effectiveness, low operating costs, and the use of environmentally friendly refrigerants. Furthermore, ejectors can operate efficiently with alternative low-grade heat sources, such as energy from the sun or excess heat from manufacturing processes. However, a limitation of refrigeration and air-conditioning cycles incorporating ejectors is their relatively low coefficient of performance (COP). To address this issue and improve the overall COP, integrating the ejector into the vapor compression cycle has been proposed. This paper presents an experimental study on the integration of an ejector into the vapor compressor system. The ejector sub-cycle employs R134a refrigerant, while the vapor compressor sub-cycle uses R410A refrigerant. The impact of operating conditions on the system's COP is investigated. The experimental results demonstrate that the integrated cycle can significantly increase the mechanical COP, improving it from 21.7% to 30.7% compared to the single vapor compressor cycle.