small refrigeration/evaporation device

[Dawn6]

I need a way to cool water flowing through a 1.5mm ID tygon tube. It needs to be something pocket-sized, and I am having trouble coming up with anything like this. Any suggestions? Thanks.

 

[btrueblood]

Thermoelectric chiller? A chemical "ice pack?

To beter give you an answer we need: 1 How much water, 2 how quickly, 3 How big a pocket, and 4 any restriction on what it can have in it (nuclear power devices, batteries, fuels...)

 

[Dawn6]

1. the amount of water is small, enough to be pumped quickly through 12 ft or 1.5mmID tubing.
2. needs to cool it at a fast rate, but the deltaT is only 5 degrees F
3. I am hoping to find something 3"x3"x.75"
4. restrictions are that it should be safe to carry on your person. So, nuclear power, acidic, heavy batteries, etc. I cannot use.
Once again, thanks for the help.

 

[mcgyvr]

aquarium chiller?
peltier cooler?

 

[IRstuff]

1. the amount of water is small, enough to be pumped quickly through 12 ft or 1.5mmID tubing.

means what picoliters?

2. needs to cool it at a fast rate, but the deltaT is only 5 degrees F

means what? nanoseconds? femtoseconds?

TE cooler is one choice. Another would be Freon, CO2, or N2, or Ar.

TTFN

FAQ731-376

 

[btrueblood]

Well, that leaves us only moderately more enlightened, Dawn6 - throw us a freakin' bone, will ya? Put some numbers to the how much and how fast figures, even if they are order-of-magnitude guesses.

Thermoelectric coolers - see melcor.com, or better do a google search for that term, or peltier coolers like mac says.

Ice packs are pretty common - look in your local drug store or athletic supply store. Commonest reaction is mixing ammonium nitrate with water. If the water coming out of your tube need not be pure, consider mixing the nitrate directly. Um, caution: buying large amounts of nitrate may get you questioned by authorities.

 

[Dawn6]

Okay, I just did a little experimental test and I have a flow rate of 35mL/min through my tubing. However, I can put it in a reservoir in line with the tubing to slow it down. Sorry I can't provide many details as I am just trying out ideas at this stage and only need ideas of possible mechanisms that would work.

 

[unclesyd]

You might want to give these people a call to discuss your problem. If they can't solve it they will probably know someone else that might fit.

http://www.microcooling.com/index-javascript.php

 

[carnage1]

a can of 1,1,1,2 tetrafluoroethane would do the trick, just make sure you get the pure stuff that isn't diluted like the home "freeze sprays" use. the dilution agent doesn't evaporate like the tetrafluoroethane. (it has a boiling point below -40deg)

something like this

http://www.techspray.com/newinfo/1672.pdf

Luck is a difficult thing to verify and therefore should be tested often. - Me