Rabindra Paul

Hi Eric, 

Thanks for asking question through AIS forum. As you mentioned, you are new to Icepak, I wanted to know whether you went through introductory training. Going through introductory notes and workshop should be of help.

In any case, the wall boundary condition needs to be at the boundary of the domain. I believe you have used the suggested domain size for the natural convection. Most of the cases, the domain sides should be free openings for natural convection setup. Hoewever, if there are physical wall for the problem then you can use wall bc and define the appropriate bc. You should not use wall boundary type within the domain. The heat trasnfer from the objects to air will be handled by the software within the domain.  You can access training material from Ansys Learning Hub. Please let us know if this helps or if you have any comments.