In this paper, various eco-friendly refrigerant mixtures R430A, R436A, R436B, R435A, and R510A used in vapour compression refrigeration systems are considered for this study. All of them have zero ODP and very low GWP. On the basis of exergy features, the efficiency of various working fluids in vapour compression refrigeration cycles was compared. The exergy efficiency of mixtures is evaluated for various evaporating temperatures ranging from -40°C to -5°C at a constant condensation temperature of 45°C. The variation of exergy is also analyzed for various condensation temperatures ranging from 25°C to 60°C at a constant evaporating temperature of -10°C. The exergy losses in various components are computed and presented in Grassmann diagrams for a cooling load of 1 kW. The results indicate that all the investigated alternative refrigerant mixtures have higher exergy efficiency than R134A. The maximum exergy performance is 39.72% observed for the mixture R435A at an evaporation temperature of -30°C, and this value is 9.89% higher than that of R134a.The results also show that the highest and lowest exergy losses have occurred in the compressor and evaporator.

This study investigates the performance of nanorefrigerants (R134a-ZrO2) in a domestic refrigerator at a concentration of 0.2 g/l without changing the components. Nanoparticles of ZrO2 of 0.2 g/L concentration with particle size 1-10 nm and 140 g of R134a have been charged, and investigations were carried out. Energy consumption and pull-down tests were conducted to investigate the performance of the refrigerator. The performance parameters like refrigeration capacity, compressor power, discharge temperature, coefficient of performance, and energy consumption were investigated for the nanorefrigerant (R134a-ZrO2), and the results were compared with base refrigerant R134a. The pull downtime, energy consumption, and discharge temperature are reduced with increased COP and compressor power when the system is operated with R134a-ZrO2 nanorefrigerant. Also, the thermophysical properties of the nanorefrigerant (R134a-ZrO2) are calculated and analyzed for the various volume fraction of nanoparticles.

Dimethyl ether (DME) and its blend of refrigerants (R429A, R435A, and R510A) are considered in this study's second law analysis as potential replacements for R134a. The performance of various refrigerants in a vapour compression refrigeration system is examined using the Design package CYCLE D. The software REFPROP 9.0 is used to extract all of the thermal and physical parameters of DME and its blend of refrigerants. The Second law performance parameters such as Efficiency Defects, Entropy generation and ExergyEfficiency are discussed. The refrigerants R429A and R510A are more energy efficient than R134a across a condensing temperature range of 30 to 55 °C at − 10 °C evaporation temperature. R134a was exceeded by R429A and R510A in terms of exergetic efficiency by 2.08 and 0.43%, respectively. In comparison to other losses in different components, the compressor's exergy loss is larger at 37–40% of the total exergy loss. By employing RE170 and its blends, the Vapour Compression Refrigeration System often performs better under the second law than R134a.The result shows that the efficiency defects in the compressor are the largest, followed by the condenser and evaporator. Thus, the design improvement of a compressor is of at most importance to improve the system performance by lowering the overall irreversibility.

The household heating and cooling system often use the capillary device. The use of the helical capillary eliminates the need for lightweight refrigeration devices in the system. Capillary pressure is noticeably affected by the capillary geometric parameters, such as length, mean diameter, and pitch. This paper is concerned with the effects of the capillary length on the performance of the system. Three separate length capillary tubes were used in the experiment. The data on R152a were studied under various conditions to assess the impact of varying the length. Maximum COP is obtained at an evaporator temperature of − 12 °C and capillary length of 3.65 m. The result is drawn that the system performance enhances when the capillary length is improved to 3.65 m when compared to 3.35 m and 3.96 m. As a result, as the capillary length increases up to a specific amount, the system's performance improves. The findings from the experiment were compared with those from the computational fluid dynamics (CFD) analysis.