Effect of Temperature and Nanoparticle Concentration on Free Convective Heat Transfer of Nanofluids

A theoretical analysis of the influence temperature and nanoparticle concentration on free convection heat transfer from a horizontal tube immersed in an unbounded nanofluid was presented. The Nusselt (Nu) number coefficient were parameters intensity convective transfer. For convection, Nu function Rayleigh (Ra) Prandtl (Pr) number. functions thermophysical properties nanofluids. nanofluids varied with concentration. Therefore, conducted to evaluate effects performance due variations thermal conductivity, viscosity, expansion, density, specific heat, which are temperature. Water- ethylene glycol (EG)-based dispersed alumina (Al2O3) nanoparticles at mass concentrations 0.01%, 0.1%, 1% considered. Calculated numbers coefficients compared experimental values taken published literature.