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ISSN Online: 2379-1748

ISBN Flash Drive: 978-1-56700-469-4

ISBN Online: 978-1-56700-470-0

Second Thermal and Fluids Engineering Conference
April, 2-5, 2017, Las Vegas, NV, USA

NUMERICAL INVESTIGATION ON THE TURBULENT CONVECTIVE HEAT TRANSFER OF NANOFLUID FLOWS IN AN UNIFORMALY HEATED PIPE

Get access (open in a dialog) pages 3099-3110
DOI: 10.1615/TFEC2017.tpn.018120

要約

Turbulent convective heat transfers of Al2O3-water nanofluid flowing in a circular tube subjected to a uniform and constant wall heat flux are numerically investigated using different turbulence models. Three nanoparticle volume concentrations, namely φ=0.02, 0.1 and 0.5% are considered for different bulk Reynolds numbers within the range 3000<Re<20 000. The effects of the nanoparticle concentration and the Reynolds number on the convective heat transfer and friction factor are reported. Two different numerical approaches including the single-phase and the mixture two-phase models with variable thermophysical properties are favorably compared to experimental results obtained from the literature. Adding nanoparticles to the base fluid was found to significantly improve the average heat transfer coefficient. The Nusselt number increases with increased nanoparticle volume concentration and increased Reynolds number, whereas the friction factor decreases with increased Reynolds number. Seven turbulence models in their low-Reynolds number formulation were also compared to assess their ability to predict the effect of turbulence on the convective heat transfer. The SST k-ω model was found to perform the best with errors in terms of the average Nusselt number and friction coefficient of 0.44% and 1.82% respectively. On the contrary, the Reynolds Stress Model completely failed to provide the good values with discrepancies of 41.91% and 133.54%, respectively.