View Full Version : Liquid at -80C?
JacobHansen
10-24-2005, 06:25 AM
I use dryice for almost all my benching here in Denmark, therefor i was wondering if it could be possible to find a liquid that remains liquid at -80C .. I know that Cooling fluid for cars can to go ~ -40 C..
Iam still looking for something more.. As allways ;)
Please post anything that you could think of.. ?` :clap:
Fresh Daemon
10-24-2005, 06:40 AM
90% methanol by weight in water should freeze at about -145C. Trouble is it's very volatile, flammable and toxic.
metro.cl
10-24-2005, 06:58 AM
alcohol? acetone?
chew*
10-25-2005, 08:59 PM
denatured alchohol is rated to stay liquid till -100
nachthymnen
10-26-2005, 01:13 AM
denatured alchohol is rated to stay liquid till -100
For my bench with DI I use alchool ethilic...for sure it's liquid until -80...
Cossey
10-26-2005, 01:14 AM
ethanol feezes at -114oC
acetone freezes at -95oC
either is fine but check that the loop is compatible with acetone as it eats most plastics and tubes.
Would it be best for high negative temperature liquids to use metal tubes (insulated)
Thats a hold-back for me at the mo...finding a "safe" liquid that can handle -35-45 and have a secure loop to move it around is a hassle
Vincentvega18
10-26-2005, 07:06 AM
Would it be best for high negative temperature liquids to use metal tubes (insulated)
Thats a hold-back for me at the mo...finding a "safe" liquid that can handle -35-45 and have a secure loop to move it around is a hassle
Thats gonna be very tricky, even given that you could find something, your going to have problems with insultaing the tubing and stopping it from cracking. Most people on chillers use water with some anti freeze like substance to stay at around -10. -35+ youd probably be best with phase or di for benching.
Very true, and I agree but it seems like a bit of a waste to have high-capacity waterchillers only to be knee-capped by the liquid not being able to handle the temps :(
Kenny
JacobHansen
10-26-2005, 10:23 AM
Its a new projekt, so we bought an industrial pump.. hehe a big motherf*cker - i was thinking acetone, but as you said it probly eats the hoses ?..
But its only for som 3d2k1 :)
Well give it a try.. And hope it doesnt spill all over the place..
Holst
10-26-2005, 10:36 AM
Silicone tube will work down to -60.
Not sure about -80 .. I think it might be ok for a whyle... but im (obviously) unable to test it.
Fresh Daemon
10-26-2005, 11:52 AM
If it's brittle it won't matter until there's any kind of torsion put on it. Then it would crack. Of course, if it's brittle enough the stress of liquid flowing through it could crack it.
Bear in mind that as a liquid gets closer to its freezing point the viscosity increases. If you get something that freezes not far below what you're cooling it to, it's going to be like pumping treacle.
Oh, and I have to ask, if you are using phase-change, nitrogen, dry ice etc. to cool this fluid, how come you don't just use it to directly cool the processor? Is it because you also want to cool GPU(s) with it? Direct-die would be less hassle, I think.
JacobHansen
10-26-2005, 11:57 AM
The FX is being cooled by dryice, and until my gpu tubes are being manufactured i have to do something temporairy... :)
JacobHansen
10-26-2005, 01:33 PM
But i still dont know if the silicone hoses will perrish at the extreme cold!... :(
Dragoon42
10-26-2005, 05:22 PM
dude this is freaking insane. DI + this hehehe. Just outta curiosity what card are you planning on cooling with this?
JacobHansen
10-27-2005, 10:48 AM
dude this is freaking insane. DI + this hehehe. Just outta curiosity what card are you planning on cooling with this?
2x7800gtx.. :D
Holst
10-27-2005, 10:50 AM
But i still dont know if the silicone hoses will perrish at the extreme cold!... :(
I found the spec for medical silicone, which stated it will be ok upto -60*c
Im not sure if this is the same as the regular silicone I use, or what will happen if you try and go to -80.
Can you put a cap on one end of the tube and just pour in some dry ice and methanol (or whatever your using) and see if the tube is damaged afterwards?
JacobHansen
10-27-2005, 11:10 AM
I found the spec for medical silicone, which stated it will be ok upto -60*c
Im not sure if this is the same as the regular silicone I use, or what will happen if you try and go to -80.
Can you put a cap on one end of the tube and just pour in some dry ice and methanol (or whatever your using) and see if the tube is damaged afterwards?
I will try tonight, if i can finde some silicone tubes.. I just got som Dryice to test it with.. In Theori the silicone tube should stay intact, as long as i dont touch it?.. Then it will not break - or will the silicon expand under xtreme temps... Well, its worth a try!..
Fresh Daemon
10-27-2005, 11:14 AM
In Theori the silicone tube should stay intact, as long as i dont touch it?
I wouldn't bet on that. Thermal stress alone from the temperature differences at the ends of the tubing might be enough to crack it if it's already below it's safe operating temperature.
JacobHansen
10-27-2005, 01:07 PM
Well - i just made an mini experiment witht the Acetone and sme dryice. The tubes didnt leak - lets just say it like that.. Damn, then bursted into little pieces if i grabed them..
So i think ill go the local Construction Store and pick up some nice coated tubes!
ยจ
edit : I should mention that the silicon tubues i justed were about 8-12 months old.. So i dont know if its the age of the tubes or the product it self.. ? :confused:
What about the perspex on your blocks? And your pump....
JacobHansen
10-27-2005, 01:34 PM
I will try to make the pump circulate the cold liquid sometime next week. This weekend is scheduled for some gaming!
Thanks for all the great answers :toast: , ill post somepictures with the result next week.
SlackeR
10-27-2005, 02:11 PM
Watch out - acetone eats a lot of plastics. I would try some on a corner of any plastic you might have on waterblocks etc.
I yhink Tygon tubing might work very well, i think i heard it was developed for the medical and chemical industry. I don't know, though, and you might be able fo find something just as good anywhere else.
The Bossman
10-27-2005, 07:58 PM
I saw some glycol based fluid today that said it could handle -100c... I'll buy a couple gallons and take some pics to show ya..
JacobHansen
10-28-2005, 06:14 AM
Thanks alot Bossman!.. I did not make it to the store today, so oll do it next week. On sunday ill do some more testing with some waterhose - that should be alot harder than silicon tubes..
Dragoon42
10-28-2005, 06:29 AM
You could also pm chilly1 and ask what he uses. Last time we talked he mentioned a -90c chiller.
The Bossman
10-28-2005, 03:08 PM
sorry, I was wrong. The crap I looked at was normal anti freeze type, except it was blue. Only good to -74c.