Natural Convection of a Nanofluid in A Square Cavity Using Lattice Boltzmann Model

In this paper, laminar natural convective of a nanofluid in a square cavity is studied using Lattice Boltzmann Model (LBM). The main objective is to investigate theeffects of thermal conductivity and variable dynamic viscosity models of Al2O3–water and TiO2–water nanofluids on heat transfer in this geometry. Theinfluence of pertinent parameters such as solid volume fraction of nanoparticles (0≤φ≤5%) and Rayleigh number (Ra = 103 _ 106) on flow and heat transfer areinvestigated. Good agreement was observed between the present results and those of previous work using conventionalCFD techniques. It is found that fluid flow and temperature field are affected by addition of nanoparticles into water. A deterioration of the meanNusselt number was observed with increasing volume fraction of the nanoparticles for the whole range of Rayleigh number while it increases with the increasingRayleigh Number. It is also indicated that average Nusselt number was more sensitive to the viscosity models than to the thermal conductivity models

کلیدواژه ها:

natural convection ، nanofluid ، square cavity ، variable properties ، Lattice Boltzmann Model