Exergy-Based Sustainability Analysis of a Two- Stage Vapour Compression Refrigeration System Using Hybrid Nano-Refrigerant

Refrigeration technology is designed to provide cooling based on the principle of rejection of heat to the surrounding at higher temperature and absorption of heat at low temperature. The performance of a vapour compression refrigeration system can be enhanced by improving the performance parameters of the system. In this study, comparative analysis of hybrid Nano refrigerant and R134a only as refrigerants in two stage vapour compression refrigeration system has been done on the basis of energetic and exergy-based sustainability performance. The performance parameters of the system such as the coefficient of performance (COP), exergy destruction and sustainability index were investigated experimentally at different temperatures of the evaporator and condenser, and also at different volume concentrations of the Nano-particles using TPS-3950, TPS-3951 and TPS-3952 equipment. It was later validated using the Engineering equation solver software. The results obtained show that at evaporator temperature of 243°K and condenser temperature of 321°K, the COP of the system increased by 7.8%, exergy destruction decreased by 16.9% and sustainability index decreased by 1.6% using the hybrid Nano refrigerant when compared with pure refrigerant. It was also observed that the coefficient of performance is higher when using hybrid Nano-refrigerant when compared with using R134a only. The sustainability index and Exergy destruction of the system is smaller when using hybrid Nano-refrigerant when compared with using R134a only. It was observed that the coefficient of performance and sustainability index increases with increase in evaporator temperature. While the exergy destruction of the system decreases with increase in evaporator temperature. Also, the COP decreases with increase in condenser temperature. While the exergy destruction and sustainability index of the system increases with increase in condenser temperature. The COP increases with increase in volumetric concentration of the hybrid Nano particles. Whereas, the sustainability index and exergy destruction of the system decreases with increase in volumetric concentration of the hybrid Nano particles. In conclusion, the system performs better using hybrid Nano-refrigerant but it is less sustainable.