An experimental study on rheological behavior of non Newtonian hybrid nano coolant for application in cooling and heating systems
In this paper, the rheological behavior of COOH functionalized MWCNTs SiO2/EG water hybrid nano coolant for application in cooling systems at temperatures ranging from 27.5 Ct o 50C has been examined. Stable and homogeneous suspensions, with solid volume fractions ranging from 0.0625% to 2% were prepared by dispersing dry MWCNTs and SiO2 nanoparticles (50:50 vol. in a specified amount of a binary mixture of EG water (50:50 vol. Viscosity measurements were performed at the shear rate range of 0.612 s 1 to 122.3 s 1 for each nano coolant sample. Results showed that the base fluid exhibits Newtonian behavior and the nano coolant samples exhibit a pseudoplastic rheological behavior with a power law index of less than unity (n 1) The results also revealed that the apparent viscosity generally increases with an increase in the solid volume fraction and decreases with increasing temperature.