VISCOSITY OF ETHYLENE GLYCOL+ WATER BASED Al_2O_3 NANOFLUIDS WITH ADDITION OF SDBS DISPERSANT

摘要

During the last decade many studies have been conducted on the thermophysical properties of nanofluids as a new medium in heating and cooling systems. However, few studies are available on the viscosity of nanofluids especially in the presence of a dispersant. In heat transfer systems, the viscosity of fluid is an essential factor for pumping power estimation. This study focused on the viscosity of Al_2O_3 nanoparticles, at concentrations of 0.01-1.0% dispersed in the mixture of ethylene glycol+water (mass ratio of 60:40) with addition of sodium dodeobcylbenzenesulfonate (SDBS). Results indicate that nanofluids with higher Al_2O_3 nanoparticle concentrations have higher viscosities. It is also interesting that, nanofluids with low volume concentrations showing almost same viscosity values, which might be due to well dispersed nanoparticles as a result of the SDBS dispersant. However, at high concentrations the SDBS dispersant negatively influences the viscosity of nanofluids. In addition, the viscosity of the nanofluid significantly decreases with rising temperature.