Rob
Ansys Employee

OK, for mesh resolution near the walls you want to look at inflation. Read up on combining inflation with swept meshes; whilst it's easy it's not immediately obvious how it works. 

Inlet and outlet temperatures in Fluent mass weighted average on the surface? Or a point value more akin to the experiment? How do you differentiate from heat coming from a fluid zone of smaller annular diameter against from a higher annular diameter?