wrote:
Doug Miller wrote:
(David Combs) wrote:
I recall from a thermodynaics course eons ago that... the amount
of heat energy flowing from one to the other, per second, is 100%
*proportional* to the temperature *difference* between the two.
With respect to conduction, yes...
It is also true for Newton's law of cooling which governs
conventive heat transfer.
Conventive? :-)
Radiant floor heating heats your feet by conduction...
Not much, compared to the rest of your body.
Radiative heat transfer is negligible...
Wrong.
Even though readiative heat transfer is proportionate the difference
in the Fourth Power of th eabsolute temperature, the coefficient is
typicall very small compared to the convective heat transfer
coefficient...
A 90 F body in a 70 F room might lose 30 Btu/h-F-ft^2 by convection and
0.1714x10^-8((90+460)^4-(70+460)^4) = 22 Btu/h-F-ft^2 by radiation.
Nick