Numerical Investigation of Al2O3/Water Nanofluid in Horizontal Elliptic Ducts Using Two Phase Mixture Model

In this paper, the effects of volume fraction of nanofluid Al2O3/water under laminar mixed convection flow in horizontal elliptic ducts with uniform heat flux at the solid liquid interface has been studied employing two phase mixture model. The fluid flow properties are assumed constant except for the density in the body force, which varies linearly with the temperature (Boussinesq's hypothesis), thus the fluid flow characteristics are affected by the buoyancy force. In the present study has been carried out for constant Reynolds number and then constant mass flow rate. Three dimensional elliptical governing equations have been discretized using the finite volume method (FVM) to investigate fluid flow throughout of elliptic ducts. It is found that at the constant Reynolds number, increasing of solid nanoparticles volume fraction thermal characteristic improved but pressure drop and shear stress increased. Also in the constant mass flow rate, increasing of solid nanoparticles volume fraction increased pressure drop, pumping power and temperature difference of inlet and outlet flow in the elliptic duct. By using of the mixture model for simulation of nanofluid it is observed that although improve thermal properties but pressure drop increase that its not desirable.