Spatially Advancing Curved Channel Turbulent Heat Transfer with Iso-Thermal Wall Heating Condition

Spatially advancing curved channel turbulent heat transfer was simulated directly for the iso-thermal wall heating condition. The Reynolds number was almost 20,000 which was based on the mean velocity and the channel width. The mean values and turbulence statistics were investigated for how they change under influence of the organized large-scale vortex growing to fill almost whole channel width. The spatial development of mean velocity and mean temperature roughly resemble each other. However, there are conspicuous difference in respect to the reverse gradient diffusion phenomena between flow and thermal fields. In the thermal field, the position of maximum temperature differs largely from the position where the turbulent heat flux takes zero. It is indicated that the large-scale organized vortex contributed for the scalar mixing in the long distance and resulted in the reverse gradient diffusion in thermal fields.