Temperature ballance, two systems

[newguy1199]

Hi, I would like to ask you for advice with a problem, I'm working on.

I have a regular shape object (glass cylinder) in which is the 100W heat source. The heat source is ind the middle of cylinder and radiates heat uniformly throughout it’s height. Heat, of course, gradually moving into surrounding area. Thy cylinder is closed on both ends by heat insulating material. I need to know the temperature at which the air in the cylinder stabilizes and there is a temperature balance between inner and outer space. Please help as I should come to a result. Thank you and please pardon my english.

 

[jbriggs444]

Is this class work?

 

[newguy1199]

No, It is real problem I want to solve - I'm trying to develop and later produce something, but I need to determine a proper material for cylinder (right now i consider using PMMA or glass), because of low safe temperature point of PMMA. Thats it

 

[Chestermiller]

Where is the air located? Can you provide a diagram?

 

[russ_watters]

How big and how thick is the cylinder? Sounds like a light bulb to me...

 

[newguy1199]

https://ibb.co/nPBMov

 

[russ_watters]

Did I miss the length?

If it isn't too long, the heat transfer will be dominated by radiation and the problem can be made easy...