Investigation on thermophysical properties of zinc oxide nanofluid for heat transfer applications

In this present work, nanosize zinc oxide particles were prepared via modest coprecipitation synthesis route. Powder X-ray diffraction pattern was applied for calculating the size of crystallites in the prepared sample. Fourier Transform Infra-Red spectrum established the Zn-O bands at 539 and 433 cm−1 in nano ZnO sample. The structural analysis was done using Scanning Electron Microscopy (SEM) studies for ZnO nanoparticles. Ultrasonicated two step procedure was followed to disperse the produced nanoparticles in the combination of water (60%) and ethylene glycol (40%) to produce ZnO nanofluids with five different particle volume fractions from 0.0125% to 0.1%. To overcome the stability problem and uniform distribution of nanoparticles within the fluid, Cetyl Trimethyl Ammonium Bromide (CTAB) dispersant was added within the suspension while preparation. The investigation results of viscosity, density as well as thermal conductivity at various temperatures showed the enhanced results than the base fluid combination. Huge improvements in thermophysical properties leads the ZnO nanofluid as an alternate working liquid in heat transferring systems.