It is true, black surfaces are better at radiating heat. However, you will
only find black paint being applied
to automotive radiators, and old ones at that. Industrial heat exchangers are
not painted thusly. Nor are the
superior aluminum radiators. It is only the copper and brass automotive
radiators that are painted, and only
those manufactured after about the mid 1940's. I suspect, though I do not
know, that this goes back
historically to prevention of a patina buildup which may impede heat transfer.
>>> J Constantino <jjcon2@yahoo.com> 08/08 12:41 AM >>>
Thermodynamics and Heat Transfer were not my favorite
courses in school, but if I remember correctly the
emissivity value for a flat black surface was the best
for shedding heat by convection and radiation.
So while copper fins might look cool, they won't cool
as well as black (as long as the paint doesn't act as
an insulator.)
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