Investigation of the Flow Characteristics of Titanium - Oxide - Water Nanofluid in Microchannel with Circular Cross Section

The presented paper reports the analysis of the flows characteristic of TiO 2-water nanofluid flowing inside a horizontal microchannel with circular cross section area. The flow is investigated by CFD techniques using a finite volume method. A recently introduced viscosity correlation was used to model the effective viscosity of the nanofluid. A range of Re number is tested in the present study. Various temperature ranges were used as constant temperature boundary conditions. The increase of the nanoparticle volume fraction was found to increase the heat transfer rate; water showed less enhancement in heat transfer compared to the nanofluid. The increase in Re number promoted Nu number. The effect of the temperature on the effective viscosity in the channel was also reported. The change of the velocity in the entrance region was studied and discussed. The velocity gradient in the microchannel is calculated, and the results are shown and discussed.