Abstract
In this article, turbulent convective heat transfer of Al2O3–water and TiO2–water nanofluids through an annular channel have been studied numerically. A comparison was made between single-phase and two-phase models (mixture and Eulerian) to find out which one predicts experimental data more accurately. Effects of some important parameters such as nanoparticle type, nanoparticles concentration, and Reynolds number on heat transfer rate of nanofluids have been investigated. Results reveal that the Nusselt number improves with raising the nanoparticle concentration and Reynolds number. Also it has been observed that in all nanoparticle concentrations, two-phase models give closer results to experimental data comparing to single-phase model.