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A 100% passive solar heated bungalow - Page 2

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Posted by David Delaney on February 23, 2004, 1:41 pm
On 23 Feb 2004 08:00:30 -0500,
nicksanspam@ece.villanova.edu wrote:

The ceiling of the south half of the bungalo is 8
feet, say, above the floor. The ceiling above the
north half of the bungalow is 16 feet, say, above
the floor. The heat store is located above the
ceiling of the south half of the bungalow and is
therefore on the same level as the upper eight
feet of the 16 foot air space of the north half.
The 8 foot high north wall of the heat store has
manually dampered slots at the top and bottom. Hot
air convects out of the top of the north wall of
the heat store and moves across the 16 foot
ceiling, falls to the 8 foot level and reenters
the heat  store at the bottom of the north wall, 8
feet above the floor.  The hot ceiling and upper 8
feet of the 16 foot high space heat the lower part
of the bungalow by radiation.  This might be
suppplemented by a push down ceiling fan, but
radiation alone might be enough to keep the house
livable even if the pushdown fan is not working.

This arrangement may be seen in the drawing at

This explanation, and a drawing,  should have been
included in the introductory material at
I'll update it.


Posted by David Delaney on February 23, 2004, 2:03 pm
On Mon, 23 Feb 2004 08:41:00 -0500, David Delaney

Opps. I got the link wrong.

Wrong. It should be

Posted by David Delaney on February 23, 2004, 10:27 pm
 On Mon, 23 Feb 2004 09:03:28 -0500, David Delaney

David Delaney, Ottawa

Posted by bw on February 23, 2004, 9:07 pm
In fluids (such as air) warmer usually means less dense.  The less dense air
is displaced by cooler.  So it moves up and cooler gas moves down.  Bulk flow.
Sometimes the flow is contained in a loop and as long as the density
difference is maintained, the fluid (and heat) keeps flowing.  this is called

Heat is contained in mass.  So you can move heat by moving the mass, this is
called bulk flow, aka convection.
Heat without mass can move in the sense of radiation, infrared light
basically. this is not bulk flow.
Heat in solid mass can move within the mass, and in direct contact with other
mass by conduction. this is not bulk flow.

In a house you can also have combinations of all three heat transfer modes.
Sometimes it helps to draw a diagram.
Brent wegher

Posted by ~^Johnny^~ on March 5, 2004, 6:47 am

In the trade,  it's known as "buoyancy".  :-)
            wide-open at throttle dot info

Maybe I should ask Radio Shack.  They claim they've got answers;
but frankly,  if Radio Shack were our provider,  we'd _really_ be in
trouble now,  wouldn't we?

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