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Old 26-10-2009, 01:09 PM
Ironbird (Terri)
Castor & Pollux

Ironbird is offline
 
Join Date: Oct 2009
Location: Toronto, Ontario, Canada
Posts: 37
kwik follow-up notes_02

Quote:
Originally Posted by bojan View Post
True.. what I was thinking ??? anyway, instead of water, some other liquid may have been used to go below zero...
Only if that other liquid is sent through a refrigeration cycle of some description. Circulating freon does not for refrigeration make. It makes for heat exchange possibly but not active cooling (refrigeration).

Advantage to my CHILL OUT cooling is zero vibration .. vibration from thermally induced contraction and expansion perhaps. But not from a cooling fan.

For adiabatic-expansion cooling (of thermal IR cameras) as heavy a gas as possible is employed...Argon typically. The greater the atomic mass the greater the delta T for a given mole of gas (flow). Nitrogen is also used but it requires twice the volumetric flow-rate for the same delta T.

Normal welding Ar contains CO2 which would clog the fine delivery tube at the sensor end .. Lab grade Ar was preferred for continuous operation. Otherwise only intermittent operation while the CO2 had to warm up enough to sublimate. Plus those cameras (Hughes Probe-Eye) used small cylinders that operated at around 5000+ PSI compared to a scuba tank of around 3200 PSI. It required a special compressor to fill. All in all - impractical.
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