Fluid across cylinder with heat source

Hi!

I am doing a small project about an heat exchanger. First I should study the Reynolds number effect and the vortex shedding.
I already have some results about that (I should be able to calculate the Strouhal number but I don't know how) so now I am studying the heat transfer.

I have a cylinder wich is the source of heat. I set Temperature as the boundary condition in the tube and in the inlet, convective flux in the outlet and insulation in the walls. The problem is that I think I am not getting the right values. If I go to the domain plot parameters and try to plot the convective flux in the cylinder, I get the zero value. Maybe it is correct because the convection starts to happen in the layer between the cylinder and the fluid. Please correct me if I am wrong!

I have 2 versions, but I think the simnova2 is the right one, because the other one doesn't show differences when I change velocity.

Unfortunately in the university I only have the comsol 3.5 avaiable.
Can you please check if I am doing it right?

PS: Sorry my english but I am not a native speaker