TAGRA 2025

The forced convection heat transfer behavior of water-titanium oxide (TiO₂) nanofluid was investigated numerically in a system consisting of a hollow tube in the middle of which water flows within a star-section channel. In this study, the motion and heat transfer of the nanofluid were modeled under the assumption of single-phase flow and the channel walls were evaluated under the condition of constant heat flux. Continuity, momentum and energy equations were solved numerically to describe the behavior of the fluid. Calculations were made using the finite volume method and the SIMPLE algorithm was preferred for pressure-velocity coupling. In the investigation, parameters such as Reynolds number, nanoparticle concentration in the nanofluid and particle diameter (in the range of 20-100 nm) were varied and the effects of these variables on the Nusselt number and overall heat transfer performance were analyzed. The accuracy of the obtained results was tested by comparing them with the simulation results of the same system using only pure water. The study findings show that the Nusselt number; The results show that the heat transfer coefficient increases significantly with increasing titanium oxide concentration in the nanofluid, decreasing the nanoparticle diameter, and increasing the Reynolds number. This demonstrates that nanofluids are an effective solution for enhancing heat transfer performance, especially in channels with complex geometries.