NUMERICAL INVESTIGATION OF FORCED CONVECTION OF NANOFLUIDS IN CHANNELS

In this paper developing turbulent forced convection flow of a water–Al2O3 nanofluid in a square channel submitted to a constant and uniform heat flux at the wall is numerically investigated. A single model and two-phase models (discrete particles model and mixture model) are employed with constant temperature properties. The investigation is accomplished for a size particles equal to 38 nm. The CFD commercial code Fluent is employed to solve the problem by means of finite volume method. Convective heat transfer coefficient for nanofluids is greater than that of the base liquid. Heat transfer enhancement is increasing with the particle volume concentration but it is accompanied by increasing wall shear stress values. The effect of Reynolds number is great for higher concentrations. The results obtained by tree different models are presented in terms of temperatures and velocity distributions, relative increasing of heat transfer coefficient, hr, and Nusselt number profile.