Turbulent Heat Transfer Behavior of Nanofluid in a Circular Tube Heated under Constant Heat Flux

The aim of the present study is to disclose the forced convective heat transport phenomenon of nanofluids inside a horizontal circular tube subject to a constant and uniform heat flux at the wall. Consideration is given to the effect of the inclusion of nanoparticles on heat transfer enhancement, thermal conductivity, viscosity, and pressure loss in the turbulent flow region. It is found that (i) heat transfer enhancement is caused by suspending nanoparticles and becomes more pronounced with the increase of the particle volume fraction, (ii) its augmentation is affected by three different nanofluids employed here, and (iii) the presence of particles produces adverse effects on viscosity and pressure loss that also increases with the particle volume fraction.