Surface Tension and Viscosity of Aluminum Oxide Nanofluids

Nanofluid is a kind of new engineering material consisting of solid nanoparticles with sizes typically of 1-100 nm suspended in base fluids. Due to the importance of thermophysical property on the heat transfer behavior of fluids, the surface tension and viscosity of Al2O3-H2O nanofluids were investigated. The tests of nanoparticle concentrations ranged from 0 g/l to 1 g/l. The measurements of surface tension and viscosity were equipments based on the maximum bubble pressure method and a capillary viscometer, respectively. The results showed that the surface tension and the viscosity of nanofluids are both highly dependent on the temperature, which is the same to those of water. Because the nanoparticle concentration studied in this work is very low, so there is no obvious change for the viscosity and a maximum enhancement only about 5% for surface tension is obtained at a concentration of 1 g/l.