Numerical investigation of convective heat transfer of nanofluid flow over a heated circular cylinder and the effect of thermophysical models

One of the ways to increase the efficiency of tube heat exchangers is using nanofluid as working fluid. The heat transfer and exerted forces of flow over a cylindrical tube have been studied widely. In this paper, the convective heat transfer characteristics and fluid flow through a heated circular cylinder, for low Reynolds numbers of water-based nanofluid in the steady cross-flow regime have been investigated numerically. The governing equations include: continuity, momentum and thermal energy have been solved by the standard finite volume method. Two-dimensional steady flow filed computation were carried out for an uniform velocity and volume fractions range of 0.01≤φ≤0.05 over a range of Reynolds number from 10 to 30 and flow and heat transfer characteristic have been studied for Alumina/water nanofluid. The results indicate that the nanoparticles volume fraction, Reynolds number and effective physical properties of nanofluid can significantly affect the heat transfer characteristics. Adding nanoparticles to the base fluid lead to reduce the mean Nusselt number values while the heat transfer rate enhances.