it's easy, right? for example, we assume thermal resistance from ambient to surface is Theta_sa=6C/W, and conduction resistance is Theta-con=2C/W, and from inner surface to case is 8C/W. and for non-metal case, from ambient to enclosure surface is Theta-sa=6C/W, and conduction resistance is Theta-non=4C/W, and from inner surface to case is 8C/W. and we assume the total power is 5W, and ambient temp is 35C. so we can get below calculation:
(1) for metal enclosure:Tc=35+5*(6+2+8)=115C, and Ts=35+5*(6+2)=75C.
(2) for non-metal enclosure: Tc=35+5*(6+4+8)=125C, and Ts=35+5*(6+4)=85C.
from the above, we can see the difference from these two cases.
from thermal theory, if the two enclosure is same except for their material, the differene of their surface temperature should lie in their conduction thermal resistance. I think the convection and radiation heat tranfer should be identical.
if you anyone have the better understanding on this problem, please share with us.
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