Effect of convective transport mechanisms on heat transfer characteristics of nanofluids

Abstract

In this study, e ect of di erent slip mechanisms that can produce a slip velocity between nanoparticles and base fluid in a nano fluid flow eld has been investigated numerically. A two-phase Euler-Lagrange approach was applied to simulate heat transfer characteristics of di erent nanoparticles in a straight tube under laminar flow condition. Eff ect of di erent mechanisms such as thermophoresis, Brownian di usion, and Sa man lift force on convective heat transfer was investigated and discussed. It is noticed that only Brownian di usion and thermophoresis are important slip mechanisms in nano fluids. In di erent nano fluids, e ect of Brownian di usion and thermophoresis on convective heat transfer is di erent. While e ect of Brownian di usion is more important in CuO-water nano fluid, thermophoresis is the main slip mechanism in Al2O3-water nano fluid.