Heat Transfer Behavior of Al2O3-Water Nanofluid in Confined Cavity Heated From the Bottom

This article presents a numerical study of heat transfer in a square cavity filled with water-Al2O3 nanofluid and heated from the bottom. Mass Conservation, momentum, and energy equations are solved numerically by the finite volume method using the SIMPLER algorithm for pressure-velocity coupling. The effects of the thermal conductivity, the dynamic viscosity, the Rayleigh number, the solid volume fraction and the particle size on heat transfer by Al2O3-water nanofluid were discussed. In this paper, two correlations for viscosity and thermal conductivity of Al2O3-water nanofluid as functions of nanosolid concentration and diameter size are proposed. The numerical results have shown that the heat transfer is influenced by the particle size, the solid volume fraction and Rayleigh number. Results have clearly revealed the appearance of a hysteresis behavior of flow structure and heat transfer when increasing and decreasing the Rayleigh number.