The following summary of how steam-heat residential radiators work appeared on
another list. Is this correct thinking?
1. The majority of heat tranfer on radiators results from _convection_
(natural convection), not radiation. I think it's around 70%-80%
convection & only 20-30% radiation. The temperature delta between
the radiator and the surrounding is not large enough for radiation
to dominate. So, they really oughta be called "convectors"!
BTW - Convection refers to heat txfer from the _flow_ of a fluid
(air in this case). By "natural" convection, I mean that there's
no fan or blower. Air naturally circulates in the room through
the radiator.
John Leeke, Preservation Consultant