Performance of a domestic refrigerator in varying ambient temperatures, concentrations of TiO2 nanolubricants and R600a refrigerant charges

Abstract

This study investigates the effect of varying test conditions including ambient temperature (19, 22, and 25 C), mass charges of R600a refrigerant (40, 50, 60, and 70 g), and concentrations of TiO 2 nanolubricant (0, 0.2 and 0.4 g/L) on the performance of a slightly modified 100g R134a domestic refrigeration system. The investigated parameters include evaporator air temperature, energy consumption, coefficient of performance, and second law efficiency of the system. The results showed that the performance of the refrigeration system at 0.2 and 0.4 g/L concentrations of TiO 2 nanolubricant, improved at optimum ambient temperature and R600a mass charge conditions. At optimum conditions, the evaporator air temperature and energy consumption reduced within the range 5.26 to 26.32 %, and 0.13 to 14.09 % respectively, while the coefficient of performance and second law efficiency increased within the range 0.05 to 16.32 %, and 2.8 to 16 %, respectively. However, at other conditions (nonoptimum), the energy consumption and evaporator air temperature were higher and within the range 0.28 to 8.26 %, and 5 to 40 % respectively, while the coefficient of performance and second law efficiency reduced within the range 2.99 to 10.94 %, and 0.55 to 13.43 % respectively. In conclusion, we observed variations in the performance of the refrigerator with varying test conditions.

Performance enhancement and optimization of residential air conditioning system in response to the novel FAl2O3-POE nanolubricant adoption

“…This phenomenon is attributed to the impact of increasing the refrigerant mass flow rate for each initial refrigerant charge, which affects the compressor power input. This trend aligns with the findings reported by Adelekan et al [ 11 , 68 ]. The experimental results demonstrated that the use of nanolubricant decreased compressor work by 4.91%–17.23%.…”

“…Pure POE lubricant is introduced into the RAC system at the commencement of each assessment for the next concentration. This is done to prevent any contamination from the previous nanolubricant to the succeeding one [ 11 ]. This process is repeated three times for the FAl2O3-POE nanolubricant.…”

“…Several studies have investigated the application of nanolubricants in air conditioning systems, focusing on their impact on key performance parameters. The addition of nanoparticles has enhanced heat absorption capabilities, improving cooling efficiency [ 11 ]. Furthermore, nanolubricants have shown promise in reducing compressor work, resulting in energy savings and increased system reliability [ 12 ].…”

Performance of hydrocarbon refrigerants in a refrigerator with liquid line magnet and CNT nano-lubricant

“…Similarly, there is a reduction in power consumption from 3.09 to 25.13% with R600a refrigerant when compared to R134a refrigerant. The observed low power consumption of the system with hydrocarbon refrigerants resulted from low viscosity and pressure drop [ 30 , 31 ].…”

Evaluation of R600a blended with various quantities of CuO, Al2O3 and SiO2 nanoparticles

“…Adelekan et.al. [19][20][21] enhanced the COP by 2.99 to 10.94 percent by using titanium oxide nanoparticles at different concentrations and varied ambient temperatures at 19, 22 and 25 0 C.and also resulted with highest COP of 4.99 with 0.1g/L of titanium oxide and 40g of R600a and enhanced cooling effect of 290.33 kJ/kg.performed experiments with varied concentrations of graphene nanolubricants and varied mass charges of R600a refrigerant. The maximum COP of 0.76 and less power utilized by the compressor by 65W was obtained.…”