Area terms while using Axial Symmetry

Hello everyone,

I have what I beleive to be a somewhat simple question. I would like to model simple heat convection out of a cylindrical wire or water pipe. It really doesn't matter what it is, just that I want to model simple heat convection (natural convection of air) on a cylinder. I will use the following equation:



Where q is the heat transferred per unit time (W), A is the heat transfer area of the surface (), is the convective heat transfer coefficient, and dT is the temperature difference between the surface of the interface and the bulk fluid.

I am planning on applying this to a Total heat flux section of a "Heat Flux" boundary condition of a 2D axisymmetric cylinder. I want to know what I should do about the "A" or area term above. Should I assume that when calculating, COMSOL will multiply the boundary condition by the angle theta? If it does do this, my "Area" term should simply be the length of the cylinder and Comsol would take care of the rest. If not, should I include the entire Area term in the expression? so I would end up entering the surface area of the cylinder (but without the area of the ends in my case).

In short, which of the two should I enter this for the total heat flux term:
1. OR
2.

Thank you in advance for any help!!!

John