Abstract
Household energy consumption increases day by day because of the civilization and luxury life. In case of household refrigerator, the compressor consumes more energy. There is possibility to reduce the compressor work by increasing the heat transfer rate of refrigerant using nano-additives. Hence, the aim of the present work is to improve the performance of the household refrigerator using nano-additive refrigerant. Ceria nanoparticles (CeO2) have the potential to transfer more heat as it has higher thermal conductivity. In this research work, four types of refrigerant were prepared namely R0 (R134a), R1 (R134a + 0.05 vol% CeO2), R2 (R134a + 0.10 vol% CeO2) and R3 (R134a + 0.15 vol% CeO2) and the performance of the household refrigerator was studied using the aforementioned refrigerants. Experimental results showed that the thermal conductivity of R0 improved with the addition of CeO2 and the R3 refrigerant displayed the higher thermal conductivity of 0.057 W/mK. Further, the COP of the refrigeration system was greatly improved when using R3 (R134a + 0.15 vol% CeO2) refrigerant, which is 7.6% greater than the COP of R0 refrigerant. Moreover, the suction and delivery characteristics were enhanced while using CeO2 blended refrigerant. The results show the R3 refrigerant had the lowest compression ratio of 4.4, which was 6.03% lower than the compression ratio of R0 refrigerant. In addition, a significant enhancement in volumetric and isentropic efficiency was observed as 91.53 and 61.98%, respectively.