Numerical investigation into the convective heat transfer of TiO2 nanofluids flowing through a straight tube under the laminar flow conditions

A numerical study has been performed by using both single phase method and combined Euler and Lagrange method on the convective heat transfer of TiO2 nanofluids flowing through a straight tube under the laminar flow conditions. The effects of nanoparticles concentrations, Reynolds number, and various nanoparticle aggregates sizes are investigated on the flow and the convective heat transfer behaviour. The results show significant enhancement of heat transfer of nanofluids particularly in the entrance region. The numerical results are compared with the experimental data and reasonable good agreement is achieved. (C) 2008 Elsevier Ltd. All rights reserved.