Performance of residential air conditioning using nanoparticles as additive in the synthetic lubricant

By introducing TiO2 nanoparticles in the lubricant, the solubility between the lubricant and the refrigerant can be enhanced. Also, nanoparticles in the lubricant would cause the friction coefficient in the compressor to decrease, and therefore, the input power of the compressor reduced. An air conditioner with cooling capacity of 2.5 kW is utilized in the experiment. Five different concentrations of nanoparticles, viz.: 0.1, 0.2, 0.4, 0.5 and 0.6 gram of TiO2 in one liter of synthetic lubricant were investigated in the experiments. However, only TiO2 nanoparticles with concentration of 0.2 g/L were selected for the experiments because other concentrations did not show significant performance improvement in the system. The results showed that the air conditioner using R290 plus TiO2 nanoparticles in the synthetic lubricants worked efficiently with power input of the air conditioner decreased by about 6.34% and the cooling capacity and the COP increased by about 6.49% and 12.24%, respectively, compared to the system without nanoparticles in the lubricant.