Numerical simulation of mixed convection heat transfer of nanofluid in a double lid-driven cavity using Lattice Boltzmann Method

چکیده مقاله

Abstract In this study, mixed convection heat transfer of water-Cu nanofluid in a double lid-driven cavity have been analyzed by Lattice Boltzmann Method. The double lid-driven are insulated and the side walls have sinusoidal temperature distribution. Simulations have been carried out at constant Grashof number 100, the Richardson numbers of 0.01, 0.1,1,10 and 100, temperature phase deviation of 0, , , and , the solid volume fraction from zero to 0.06 and the Prandtl number 6.57. The thermal modeling of passive scalar is applied and two separate distribution function for the flow and temperature fields are considered. In order to calculate the thermal conductivity coefficient of nanofluid, constant and variable properties models are used. The results showed that in high Richardson numbers, the effect of the thermal phase deviation changes on the flow pattern is evident and in low Richardson numbers, the phase deviation changes do not affect the flow pattern. In all thermal phase deviation by reducing the Richardson number, the Nusselt number increases and thus the heat transfer increases. Also the average Nusselt number obtained for the constant properties model are higher compared with those of variable properties model.