Exergy analysis of refrigeration system using R600a with TiO₂ Nano lubricant

The irreversibility and second law efficiency of a household refrigerator using TiO₂ Nano lubricant in R600a refrigerant were evaluated using 0.2, 0.4 and 0.6g/L of Nano lubricant in R600a refrigerant. K type thermocouples were connected to the refrigerator components (compressor, condenser, evaporator, and expansion valve) at the inlet and outlet, also two pressure gauges were connected to the compressor to measure the suction and discharge pressure of the system, these values were used to determine the performance of the system using refprop version 9.1. The results showed that The total irreversibility in 0.2 and 0.4g/L TiO₂ Nano lubricant with R600a reduces with 1.5 and 3% and the same with 0.6g/L TiO₂ Nano lubricant when compared to the based fluid. The efficiency 0.4g/L of Nano lubricant was the highest with 45% higher than pure R600a in the system. Generally, R600a with TiO₂ Nano lubricant performed better than the based fluid in the system.