Comparison between multi-walled carbon nanotubes and Titanium dioxide nanoparticles as additives on performance of Turbine meter oil nano lubricant

This research work purpose to compare the impact of the mass fraction of multi-walled carbon nanotubes (MWCNTs) and Titanium dioxide (TiO 2 ) nano additive on the tribological and thermophysical attributes of turbine meter oil. These attributes are including the average friction coefficient, pressure drop, wear, flash point, pour point, relative viscosity, kinematics viscosity, and viscosity index. Also, the pressure drops and the average friction coefficient inside the copper tube were simulated and compared with experimental results. In this study, for the synthesis of nano lubricants from turbine meter oil as a pure fluid and from MWCNTs and TiO 2 as nano additives in the mass fraction of 0.05, 0.1, 0.2, 0.3, and 0.4 wt.% and from oleic acid and Triton x100 as surfactants were utilized. The diameter of MWCNTs and TiO 2 nano additives were ranging from 5 nm to 16.1 nm and 7.9 nm to 13.9 nm, respectively. The average particle size of TiO 2 and MWCNTs nano additives in 0.4 wt.% in the pure lubricant were 221 nm and 320 nm, respectively. The results illustrated that the wear depth of copper pins in the presence of nano lubricant with 0.4 wt.% of MWCNTs and 0.1 wt.% TiO 2 was improved by 88.26% and 71.43%, respectively. Nano lubricants with 0.3 wt.% of TiO 2 and 0.4 wt.% of MWCNTs nano additives illustrated the maximum improvement in the flash point temperature with enhancement 4 °C and 10 °C. By increasing of 0.3 wt.% of TiO 2 and MWCNTs into the pure oil caused to improve in viscosity index with enhancement 6.68% and 2.43% compared to the pure lubricant, respectively. The simulation data and experimental data for the pressure drop were closer together and indicated a minor error that the maximum error is less than 10%.