Keywords: refrigerants, lubricants, nanoparticles, exergy flow rate, refrigerator exergy efficiency, exergy analysis, nanotechnology, hydrocarbons, mineral oil, titanium oxide
Exergy analysis of hydrocarbons mixture refrigerants R436A and R436B as a drop in replacement for R134a with TiO2 nanoparticles
The refrigerator exergy efficiency (EE) with nanoparticles in the working fluid was investigated experimentally. Mineral oil (MO) with TiO2 nanoparticles mixtures were used as the lubricant instead of Polyol ester (POE) oil in the R134a, R436A (R290/R600a–56/44–weight %) and R436B (R290/R600a–52/48–weight %) refrigerator. The results indicate that R134a, R436A and R436B and MO with TiO2 nanoparticles work normally and safely in the refrigerator. The refrigerator EE (34.1, 40.1 and 41.6%) was better than the R134a, R436A and R436B and POE oil system (23.4, 35.3 and 37.7%). The same tests with Al2O3 nanoparticles showed that the different nanoparticles properties have little effect on the refrigerator EE. Thus, TiO2 nanoparticles can be used in refrigerator to considerably increase the EE.