TY - JOUR
TI - Numerical simulation and parametric study of laminar mixed convection nanofluid flow in flat tubes using two phase mixture model
AU - Safikhani Hamed
AU - Abbassi Abbas
AU - Kalteh Mohammad
JN - Thermal Science
PY - 2016
VL - 20
IS - 2
SP - 415
EP - 428
PT - Article
AB - In this article, the laminar mixed convection of Al2O3-Water nanofluid flow  in a horizontal flat tube has been numerically simulated. The two-phase  mixture model has been employed to solve the nanofluid flow, and constant  heat flux has been considered as the wall boundary condition. The effects of  different and important parameters such as the Reynolds number (Re), Grashof  number (Gr), nanoparticles volume fraction (Φ) and nanoparticle diameter  (dp) on the thermal and hydrodynamic performances of nanofluid flow have  been analyzed. The results of numerical simulation were compared with  similar existing data and good agreement is observed between them. It will  be demonstrated that the Nusselt number (Nu) and the friction factor (Cf)  are different for each of the upper, lower, left and right walls of the flat  tube. The increase of Re, Gr and f and the reduction of dp lead to the  increase of Nu. Similarly, the increase of Re and f results in the increase  of Cf. Therefore, the best way to increase the amount of heat transfer in  flat tubes using nanofluids is to increase the Gr and reduce the dp.