CFD simulation on laminar forced convection heat transfer of Cu-water nanofluids inside a vertical tube

A numerical simulation based on computational fluid dynamics (CFD) with a single phase model on laminar forced convection heat transfer has been presented to determine the effects of nanoparticle concentration and flow rate of nanofluid flowing through a vertical tube under constant heat flux boundary conditions. The nanofluid consists of copper (cu) nanoparticles with a diameter of 100nm, which is mixed with water, as a base fluid with two solid volume fraction of 0.64%, 1.32% and 2.74%. Ansys Fluent 13.0 has been used for simulation. All the thermo-physical properties of nanofluids were assumed to be temperature dependent. The models given by Patel et al has been used to determine the effective thermal conductivity of nanofluid. Effective dynamic viscosity has been determined by Buongiorno model. The Heat transfer coefficient and Nusselt number depends on the Reynolds number which varies from 500-900 as well as solid volume fraction. It is observed that Cu-water nanofluid exhibits 23% increase in heat transfer coefficient and 6.05% of average Nusselt number compared to base fluid. The wall shear stress increases according to increases of volume fraction and Reynolds number.