Effect of convective transport mechanisms on heat transfer characteristics of nanofluids

In this study, effect of different slip mechanisms that can produce a velocity between nanoparticles and base fluid in a nanofluid flow field has been investigated numerically. A two-phase Euler-Lagrange approach was applied to simulate heat transfer characteristics of different nanoparticles in a straight tube under laminar flow condition. Effect of different mechanisms such as thermophoresis, Brownian diffusion, and Saffman lift force on convective heat transfer was investigated and discussed. It is noticed that only Brownian diffusion and thermophoresis are important slip mechanisms in nanofluids. In different nanofluids, effect of Brownian diffusion and thermophoresis on convective heat transfer is different. While effect of Brownian diffusion is more important in CuO-water nanofluid, thermophoresis is the main slip mechanism in Al2O3-water nanofluid. (C) 2016 Shard University of Technology. All rights reserved.