On Aug 16, 8:51*am, wrote:
On 16 Aug 2008 11:32:01 -0400, wrote:

wrote:

* * * *A very small percentaqe of the heat you radiate goes in any
one particular direction, and the amount that falls on the 'receiving
/ absorbing surface' will thusly decrease as the square of the
distance from it.

Not if the surface completely encloses you.

* * * * Good point, Nick.

* * * * If you happen to be sitting inside a radiant-absorptive ball (
a thermal variation of a Dyson Sphere, perhaps, Scotty ? ).

The MRT is solid angles weighted
by their temperatures. Multiply each area your body sees by its temp, add
the products, and divide by the total area of a reference sphere surrounding
you, containing the individual areas. You might radiate 50% to a large close
wall. As you walk away from a large wall, the near-field view factor might
still be about 50%.

And we don't need liquid helium. The MRT graph he

http://heatkit.com/html/guide2.htm#MasonryHeating

says we can be comfy in 90 F air with 40 F walls, in a bunny-free room.

Some buildings have chilled beams and ceilings for cooling. A chilled

* * * * So do many many cold rooms of various applications. *Ever hear
of static-coil ammonia systems ? *They do not work primarily by
raidant absorption, they work mainly by convection currents. *If you
were to put the coils at the floor instead of the ceiling, they
wouldn't work worth a ****.

floor would make more sense, since warm air rises. A slow ceiling fan
with an occupancy sensor and a room temp thermostat could stir up some
floor air as needed for comfort.

* * * * And thus, it is no longer a radiant system, it is convective.

* * * * Hey, here's one to work on - what if you took a bunch of Bucky
Balls IE Fullerenes, and froze them, then dumped them all in a room ?

* * * * Pls post your code for designing it when you get a chance :-)

--
Click here every day to feed an animal that needs you today !!!www.theanimalrescuesite.com/

Paul ( pjm @ pobox . com ) - remove spaces to email me
'Some days, it's just not worth chewing through the restraints.'
'With sufficient thrust, pigs fly just fine.'
HVAC/R program for Palm PDA's
Free demo online atwww.pmilligan.net/palm/
Free 'People finder' program now atwww.pmilligan.net/finder.htm

this is correct... 40F walls in a warm room create convection... it is
conduction from skin to air that removes the highest percentage of
heat from a human body.... convection provides the air flow... same
with cold beams etc.... (and evaporation of water from the skin)...

radiation is a factor but its a minor factor n the termperature
differrential range are discussing....load calc books have the math
for all of this..... on a roof though with the hot sun, radiation is a
huge factor, same though glass, convection not withstanding.


Phil scott


Phil scott