Factor Effect Estimation in the Convective Heat Transfer Coefficient Enhancement of Al2O3/EG Nanofluid in a Double-pipe Heat Exchanger

The forced convective heat transfer (CHT) coefficient of a particular nanofluid, Al2O3 nanoparticlesethylene glycol (EG) mixture, was investigated experimentally in a double-pipe heat exchanger.Nusselt number of the nanofluid for different nanoparticle concentrations as well as various operatingtemperatures was found to increase up to 23.7% using 1.0% wt of nanoparticles. The significance and novelty of this work is that 22-screening design was used to investigate the effect of factors and the results emphasized that increasing nanoparticle concentration had considerable effect on theenhancement of CHT coefficient of nanofluid. The comparison of experimental results and semiempirical correlation results showed considerable deviations for high operating temperatures and nanoparticle concentrations.

Keywords:

Nanofluid , Heat Conduction , Heat Transfer , Alumina , Nanostructure , Fluid Mechanics