Reynolds Number and Heat transfer Coefficient
 

Hello all,

Im solving a simple case in fluent of an air stream in a heated tube.
I would like to know whats the difference between Turbulent reynolds Number (Re_y) and Cells Reynolds Number. Whats the difference in calculating these and what is the most representative?
The same question stand for Wall function Heta Transfer Coefficient and Surface Heat transfer coefficient
Finally i would like to know the Nu number in the stream and i only found the Surface Nu number in the fluent contour drop down menu. Is this the Nusselt number of the air stream?
I tried to find answers on the Fluent manual but i didnt found these definitions. Please tell me if there are some information about that topics on the manual.
Thank you in advance
Happy new creative year
panos