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Re: NFC: Peltier Junction Cooling




Ouch! I am a darn engineer and all this thermodynamics scares me. Good
thing I am not a Chemical or Mechanical engineer, huh? 

On Fri, 8 Jan 1999, Andrew S Dalton wrote:
> >>Electrical work:  W = VA = 12*8.5 = 102 watts.
> >>W/Q >= 1 - Tc/Th, so Q <= W/(1 - Tc/Th).
> >>Tc = (0 + 273) K = 273 K.  Th = (50 + 273) K = 323 K.
> >>Therefore, Q <= 102 watts/(1 - 273/323) = 659 watts.
> >>
> (20 gal H2O)(8.5 lb H2O/gal)(1 Btu/lb H2O/deg F)(80 deg F - 60 deg F) =
> 3400 Btu.
> 
> The amount of time needed to go from 60 to 80 deg F would be:
> 3400 Btu/(171 Btu/hr) = 19.9 hr.
> 
> Mathematically:  Q = U*A*(To - Ti).
> 

--
Sajjad Lateef                         <http://www.eecs.uic.edu/~slateef>
sajjad at acm_org      Please Visit NFC: <http://nativefish.interspeed.net>


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