On Wed, 09 Jun 2004 14:45:12 GMT, Anthony Matonak
wrote:

wrote:
...
I sort-of beat you to it in my previous post. I agree with you, but anything
that cools the air, also increases the relative humidity, because it has
less capacity to hold moisture.

I guess it depends on how you look at it. It increases the airs relative
humidity while the air is at the lowest temperature but since the air
typically increases in temperature somewhat dramatically when mixed with
the rest of the building air it's RH drops.

How about a rack of cool desiccant ?

Desiccant cooling systems are in fairly widespread use. They typically

Yeh, I know, that's why I mentioned it :-)

operate by having a wheel of desiccant turning slowly between two
air channels. One channel has hot air flowing through it, typically
outside air (or building air being exhausted to the outside) that has
been heated by a burner. This dries out the desiccant. The other channel
has humidified air (like from the exit of a swamp cooler) that gets
dried by the desiccant. It works and it seems to me that it could be
adapted to use solar heated air.

In practical terms, the desiccant requires higher temps to dry
out.

But I was pointing out an exception to your statement
"anything that cools the air, also increases the relative humidity"

'T'aint necessarily so :-)

If you heated the desiccant ( regen cycle) then cooled it,
then passed your target air over it, you have a system that both cools
the air *and* lowers the RH :-)



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