Numerical investigation of transient single phase forced convection of nanofluids in circular tubes

Abstract

In this paper the development of the laminar forced convection flow of a water- Al2O3 nanofluid in a circular tube submitted to a constant and uniform heat flux at the wall is numerically investigated in a transient regime. A single and two-phase model (discrete particles model) is employed with either constant or temperature-dependent properties. The investigation is accomplished for a particle size equal to 100 nm. The convective heat transfer coefficient for nanofluids is greater than that of the base liquid. Heat transfer enhancement increases with the particle volume concentration, but it is accompanied by increasing wall shear stress values.