Thermal Conductivity question

[faulkma]

If i have a insulating material with a TI of 130C for example and at one point a copper conductor touches it exceeds 130C, would the temperature at the insulating material exceed 130C? or would it be something less than 130C.

I guess if I was cooking on a stove with a pan made out of insulating material and the eye was at 130C, would the bottom of the pan be at the same temp or slightly less due to the density of the material type.

thanks Much

 

[IRstuff]

Is this for school? Why would density enter into the problem? The only thing that matters is the heat balance.

TTFN

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[faulkma]

No its not for school. its more of a question of thermal conductivity with heat generated by passing thousands of amperes thru a insulation media. My instinct tells me that it is a matter of density and molecular structure of the material.

 

[electricpete]

What is "TI" in your original post?

If you a steady state problem with a single heat source and assumed ambient temperature boundary condition, then than the heat source is obviously the highest temperature anywhere in the problem (probably the center of the heat source, if it is distributed).

Your question isn't making much sense to me.

=====================================
(2B)+(2B)' ?

 

[electricpete]

Also what is "eye" in the original post?

=====================================
(2B)+(2B)' ?

 

[IRstuff]

I suggest that you read up on heat transfer, and if you have to, you can download one for free:

http://web.mit.edu/lienhard/

http://www/ahtt.html

TTFN

FAQ731-376
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[vpl]

faulkma

Your comments indicate that you might lack knowlege in about heat transfer.

On a gas stove, the "eye of the flame" will be well above the melting point of the copper bottom pots you put on the stove. The pot won't melt, even at the center -- because the copper transfers the heat.

Same is true about the insulating material. You can comfortably grasp a pot handle without burning yourself. There will be a hot spot directly where where the insulator touches the pan, but that's about it. What that temperature is seems rather irrelevant.

If you have a question about "thermal conductivity with heat generated by passing thousands of amperes thru a insulation media," then I'd suggest asking it. Asking about pots on stoves leads to the "are you a student" replies, becuase that's a pretty elementary heat transfer situation.

Patricia Lougheed

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[corus]

Density would enter the problem if you're considering the change of temperature with time. The change in temperature would be lower for a denser material. I don't fully understand the problem, but my guess is that when you initially contact material with a high temperature then there would be a rapid increase in temperature with contact before temperatures decreased as heat was lost from the surrounding surfaces.

Tara

 

[mcgyvr]

If you are using an insulating material with a UL "RTI" of 130C that is in direct contact with a bus bar that reaches more than 130C then you need to find a different material.