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Unread 09-21-2005, 07:30 PM   #93
bobo5195
Cooling Savant
 
Join Date: Aug 2005
Location: uk
Posts: 400
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There are models other than sieder tate, cant remember what they are called (huaman?? comes to mind) besides im not sure they are that helpful in this case. The heat transfer of impinged jets is hard science. Also they are exceptionally efficent and at the surface where the jet is focused they are nearly ideal, so you have to consider the whole surface rather than a point. A simple model is not going to predict to much. At the end of the day simple heat capacity minus 'losses' (thermal paste etc, might be an idea to include minimum thickness of al or cu to give a nice spread of heat on the surface as this is mostly unavoidable) this gives you a nice k value. Ie if k=1 then there is perfect heat trasfer. There are special case where k can be lower than 1 if you use pump power to cool the fluid by making it go through a sudden expanssion but using k values gives you a nice graph. The surface is not macroscaled finned as well so any finned model is an approximation to a different type.

Everything is relative after all, use of a peltier to increase the gradient (but only to just above dew point) will give substantial heat gains. Even assuming performance is the only goal is slightly pointless, as there are many factors which effect overall valuation.
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