Numerical Investigation of Laminar Convective Heat Transfer for TiO2/water Nanofluids Using Two-phase Mixture Model (Eulerian Approach)

Laminar convective heat transfer of TiO2/water nanofluids flowing through in tube has been studied numerically using a CFD code (ANSYS Fluent Release 14.5). 2D axisymmetric configuration was applied to a horizontal circular straight tube with 2000 mm in length and 4.0 mm in inner diameter. Semi-Implicit Method for Pressure-Linked Equation (SIMPLE) was performed to couple the pressure and velocity. The convergence of the iterative solution was carefully monitored less than 10(-4). The temperature distributions of nanofluids flow at Reynolds number of 900 and 1500 were mapped for a circular tube subjected to constant wall heat flux boundary conditions of 4000 W/m(2). By considering the mean temperature of nanofluids, the two-phase mixture model using Eulerian approach was performed to analyze numerically convective heat transfer for titania nanoparticle concentrations of 0.24, 0.60, 1.18 vol.%. The well-known Shah and London equation was used to validate this numerical study at developing laminar flow regime. The computed numerical data has a better agreement with the prediction from Shah-London correlation rather than the centerline temperature. The results show that the two-phase mixture model using Eulerian approach considering the mean temperature has succeeded to evaluate accurately.