TiO2 nanolubricant: An approach for performance improvement in a domestic air conditioner

Abstract

TiO2 nanolubricant has been used in this experimental work to study the performance of domestic air conditioner. Air conditioner capacity was 1 ton and the original system has R22 refrigerant. Three alternate refrigerant blends-Blend 1 (B1) composed of R32 and R22 (75:25 wt%), Blend 2 (B2) composed of R32 and R600a (75:25 wt%) and R32 refrigerant have been used in this experimental work to compare the thermo-physical performance with R22.0.01% and 0.02% volume concentration TiO2 nanolubricant have been used. All the temperatures and pressures of different section have been recorded using K-type thermocouple and pressure gauge respectively. Results showed that the selected blends with nanolubricant have higher COP compared to R22. Numerically, COP has been increased by about 25%–60% for B1 and B2 with nanolubricant and 20%–30% for R32 with nanolubricant compared to R22. R32 has shown maximum response by increasing about 60% of refrigerating effect compared to R22 while B1 and B2 have 45% more refrigerating effect. For compression work R32 with nanolubricant has similar compression work compared to R22 while B1 and B2 have 33% less compressor work required. Energy consumption has also been reduced for the blends with nanolubricant. B1 and B2 consumed 30% and 28% less power compared to R22 with nanolubricant. B1 and B2 with nanolubricant reduced the exergy loss by 40–70% while R32 reduced the exergy loss by 31% compared to R22. Overall, either B1 or B2 can also be used as an alternative of R22 with TiO2 nanolubricant.