Paper presented to the 10th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Florida, 14-16 July 2014.
Numerical simulations have been carried out on natural convection heat transfer in a rectangular cavity. The effect of distilled water-Al2O3 nanofluid on heat transfer in a rectangular cavity heated vertically on sidewalls is analysed. The effective properties of distilled water-Al 2O3 nanofluid were calculated from the correlations obtained from literature. The simulation was carried under different volume fraction concentration of nanoparticles as well as different correlations for effective properties of Al2O3-water nanofluid. The results indicate that in general adding Al2O3 nanoparticles into pure water improves its heat transfer performance; however, there is an optimum nanoparticle volume fraction which maximises the heat transfer rate for each condition. It is investigated and discussed the influence of uncertainty of available correlations for effective properties of distilled water-Al2O3 nanofluid. The effects of aspect ratios of the cavity on heat transfer were also analysed. The influence of pertinent parameters such as Rayleigh number and Nusselt number on the heat transfer characteristics of natural convection is also investigated.