The Impact of Alumina Nanoparticles Suspended in Water Flowing in a Flat Solar Collector

Abstract

In this paper, convective heat transfer of Al2O3–water nanofluid flow in straight channel is numerically and experimentally studied over Reynolds number ranges of 100–1800. The Al2O3–water nanofluid with different volume fractions of 1%, 2% and 3% were prepared and examined. All physical properties of nanofluid which are required to evaluate the flow and thermal characteristics have been measured. In the numerical aspect of the current work, the simulation results showed that there was a good agreement with the experimental data for the friction factor and the Nusselt number. And The experimental results showed that the friction factor decreased with increasing velocity due to the low strength of cohesion between the particles with increasing velocity and increase with the increase in volume fractions due to the increase viscosity of the nanofluid and the coefficient of heat transfer also increases with the increase of the volume fractions and the flow rate. The experimental results were compared with previous experimental data and there were good agreements between the results. It can be concluded that adding 3% solid nanoparticles to water improves heat transfer by (54%) with a slight increase in friction factor can be neglected.