Simple Heat Transfer to Electronics Enclosure

[dsjon10]

I need to find out what the final temperature inside an electronics enclosure. I know solar loading in watts, the power output of the electronics internal to the box in watts, and the ambient temperature external to the box. Can someone help me with the formula for finding the final temperature internal to the box? Also, how do I convert watts to joules?

Thanks for your help

 

[IRstuff]

Is this for school?

TTFN

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[ione]

"How do I convert watts to joules?" When you'll find it out let me know as I have to convert apples to pears

 

[dsjon10]

This is not for school. No prior experience in thermodynamics. Any help is greatly appreciated.

 

[IRstuff]

You didn't even take physics in college?

http://en.wikipedia.org/wiki/Joule

Conservation of energy, etc.?

http://en.wikipedia.org/wiki/Heat_transfer

TTFN

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Chinese prisoner wins Nobel Peace Prize

 

[dsjon10]

Can you please help me set up the equations so I can solve for T(internal)?

The system is in equilibrium. I know that Q(in) = Q(ex) right?

I have heat dissipation of the electronics internal (Q(in)).

I have ambient temperature T(ex). I have external Q's (Q(solar load), Q(rad), and Q(convection).

I can know the formula for Q(cond) through the wall.

I just need help with setting up the relations to work the problem.

 

[IRstuff]

Qin = Qout
Qin = Qelectronics + Qsolar + Qrad_in
Qout = Qconvective + Qrad_out

You can either use a solver or manual iteration to solve for Tinside, Tsurface_inside, Tsurface_outside

A free heat transfer book:

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

http://www/ahtt.html

TTFN

FAQ731-376
Chinese prisoner wins Nobel Peace Prize

 

[vpl]

dsjon10

You might find some of these earlier threads helpful: thread391-287363; thread391-290195; thread391-253415; thread391-300762; thread391-297199.

They all deal with heating up of spaces.

However, if they don't address your problem, you might try using the grey search button (next to the green forum button) and doing a search yourself (I only looked in this forum, and not accross the site, for example).



Patricia Lougheed

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[chicopee]

See my attachment for a solution to our problem

 

[dsjon10]

Thanks to all for your help on this issue. The equations and the links should be enough to get me going on solving this problem. Thanks!