Steam-jet refrigeration is still used to concentrate
fruit juices and similar temp sensitive substances.
There is a Scientific American article about construction
of a Vortex tube, circa late '50s, early 60's...
For solar absorption cooling, see
http://www.humboldt1.com/~michael.welch/extras/solarice.pdf
Mo' high-tech: http://www.sunpower.com

Regards, Jack

Russell McMahon wrote:
>
> James,
>
> Use of steam for refrigeration was a standard technique early this century.
> AFAIR, steam was expanded through a nozzle and drew air from a venturi tube
> (?) creating a low pressure region with accompanying cooling. Old or
> complete air conditioning  books would cover this - I have only seen it
> described once.
>
> The advantage is, as you note here, that you can convert available thermal
> energy into cooling. Also, there are no moving parts. You could also
> consider using a "kerosene fridge" type arrangement which uses heating to
> drive an adsorption cycle using, typically, ammonia and water. Only moving
> parts here are the fluid(s). This may be easier as the technology is current
> and common and you could copy an existing fridge or use an existing one and
> simply heat the appropriate point.
>
> Hilsch Vortex / Wiebel Rohr / Maxwell's ... typically seems to like around
> 100psi (7 bar / 700 kilopascal) but lower should work with suitable
> "design".
>
>       Russell McMahon
> _____________________________
>
> >From another world - www.easttimor.com
>
> What can one man* do?
> Help the hungry at no cost to yourself!
> at  http://www.thehungersite.com/
>
> (* - or woman, child or internet enabled intelligent entity :-))
>
> -----Original Message-----
> From: James Newton <eplus1@san.rr.com>
> To: pic microcontroller discussion list <PICLIST@MITVMA.MIT.EDU>;
> apptech@CLEAR.NET.NZ <apptech@CLEAR.NET.NZ>
> Date: Friday, 1 October 1999 03:48
> Subject: RE: [OT] Second Chance. Maxwell's Demon and NOT Church of England.
>
> >I had a crazy idea some time ago, about using a small, cheap solar
> collector
> >to produce superheated steam (and my father and I did build the device
> >described up to this point and it works fine) and then use a venturi to
> >trade the velocity of escaping steam for volume of air moved (inject steam
> >via a fine pitot into the opening of a pipe so that outside air is pulled
> >into the pipe) and then direct that into a Hilsch Vortex to produce
> hot/cool
> >air for house A/C.
> >
> >I would guess that back pressure at the entrance to the Vortex would limit
> >the incoming air volume excessively or that the increased temp of the air
> >(due to the steam injection) would negate any cooling gains on the part of
> >the Vortex or some such other problem would prevent it from working. The
> >nice thing would be: No moving parts other than the water and the air and
> >the collector (sun tracking), automatically starts when the sun heats it
> up,
> >super low construction cost, almost zero operating cost (only maintenance
> >and water supply).
> >