Performance improvement potential of ejector-based dual-evaporator refrigeration system using photovoltaic modules and nano-refrigerant

Abstract

This paper presents a novel system for resolving the high energy consumption of conventional vapor compression refrigeration systems. An ejector-based dual-evaporator refrigeration system (EDERS) is developed utilizing photovoltaic (PV) modules and a nano-refrigerant (NR) with 0.5 wt% of Al2O3. This novel arrangement combines four promising environmentally friendly technologies: dual-temperature cycle, ejector, PV panel, and NR. The comprehensive thermodynamic analysis and optimization of the proposed system, energetic and exergetic analysis methods are incorporated to evaluate the performance of nanoparticle (NP)-doped EDERS in this study. The results demonstrate that the use of Al2O3 NP compared with utilizing pure R134a EDERS notably improves performance under typical operating conditions. Specifically, the coefficient of performance (COP), volumetric cooling capacity, and exergy efficiency (ηex) are 7.14 %, 4.33 %, and 8.91 % higher, respectively. Moreover, the compressor power and total exergy destruction are 6.76 % and 9.94 % lower, respectively. Additionally, under the operating conditions considered in this study, the required PV area is reduced by 5.31 %–8.07 %, whereas the COP and ηex values improve by 5.64 %–8.39 % and 5.38 %–10.06 %, respectively. The study also finds that the COP and ηex values of (R600a + Al2O3) surpass those of (R134 + Al2O3), whereas the COP and ηex values of (R1234ze(E) + Al2O3) and (R1234yf + Al2O3) are smaller than those of (R134 + Al2O3). This suggests that the performance benefits of NPs may vary depending on the specific refrigerant used in the system. The results can be employed as a useful guide for the application of NRs to multi-evaporator refrigeration systems before setting up an experimental system.