Numerical modeling of nanoparticles transport effect in mixed convection of nanoï‌uid with variable properties in a square cavity with inlet and outlet port

Abstract

In this paper, the flow field, heat transfer and nanoparticles transport in Al2O3-water nanofluid mixed convection in a square enclosure with inlet and outlet port has been studied numerically. The dimensionless transport equations are solved numerically with a finite volume approach using the SIMPLER algorithm. Nanoparticles transport mechanisms such as Brownian diffusion, thermophoresis and Dufour effect that cause non-uniform concentration distribution are intended in nanoparticles transport model. The study has been carried out for the nanoparticles volume fraction in the range 0 ⤠Ïb ⤠0.04, Richardson numbers 0.01 ⤠Rif,0 ⤠1with two Grashof number Grf,0=104 , 105. The results show that in mixed convection by increasing volume fraction of nanoparticles and the Grashof number for each Richardson number, the average Nusselt number increases and the transport model by affecting on nanoparticles concentration influence the amount of flow velocity and heat transfer so that in low temperature difference homogenous model and at high temperature difference the transport model predicts higher average Nusselt number