[krokodilcho]

I am trying to create a 2D model of an insulated cylinder which has air in the annulus and a heating source in the middle (which is heating the air and the air should heat the cylinder). I hit the ground there because the results I am getting are unrealistic - seems that my boundary conditions are not defined properly.

I created named selections for the two boundary conditions I have - external temperature on the surface of the cylinder and surface of the heater; I also created named selections for each media/material. I am assigning heat flux on the surface of the heater (internal T), defining convection with certain convection coefficient for the air, and the pipe wall and the insulation walls are defined as 'walls' (without assigning any properties to them). Everything other than the 'interior' is defined as a 'wall'. Can you advise please? Thanks.