Analysis of mixed convection heat transfer of CuO-water nanofluid in a vertical square duct using two phase Euler-Lagrange approach

In this article, laminar mixed convection heat transfer of CuO-water nanofluid flow has been investigated in a vertical square duct. Constant Wall heat flux condition is considered for the walls. Governing equations are solved three dimensionally in steady state. Two phase Euler-Lagrange approach is employed to simulate nanoparticles behavior. Governin equations was discretized using control volume based finite element method (CVFEM). Effect of different parameters such as nanoparticles concentration, Reynlods number and Grashof number on heat transfer coefficient, nusselt number, velocity and temperature profiles, friction factor and particles diffusion is presented and discussed. Due to the importance of Brownian and Thermoforetic forces in nano scale analysis, effect of these forces on heat transfer rate, analyzed by Euler-Lagrange approach, is presented. Results show increasing nanoparticles concentration improves convective heat transfer coefficient, while has no significant effect on friction factor. As an example for φ=2%, enhancement of heat transfer coefficient exceed to 25%. Moreover increasing Grashof number decreases heat transfer improvement and increases skin friction on the walls.