Liquid N2? for cooling?

[Tim Lee]

At the lab I work at PSU, they have a lot of liquid N2 and I am thinking maybe I should use it for cooling. How about on the top of the cpu I make some space to place liquid N2 and seal them up. Do you think this maybe a good idea or something stupid? *) Anyone done anything like this before? Also how does water cooler work?

Thanks

Tim

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[breakit23]

Thas cool. Its a good idea its done by some companies who sell thes super cooled sytems. If u dont know no how to do it dont cus u probably [email protected]#$ up ur cpu. lol. Mabe u should try it on some crappy comp or something old that u dont use for practice. Or a freinds hehehe.

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Im out, l8r

 

[rockinwy]

yep it would be cold for about 30 seconds. its an idea but one that is too difficult to work with, liquid nitrogen in itself is easy enough to work with but it has to be under pressure to stay a liquid, i don;t know how much exactly but most likely you would never be able to hold enough pressure to keep it liquid, adding heat is only going to increase the pressure until something pops. We have a bulk liquid nitrogen tank where I work and full pressure is around 5000+ psi.

 

[Tim Lee]

I know that Air can be separated into N2, Ar, O2 at different boiling temp(pressure is lowered to low enough so that separation can be achieved at low temp it's called cryogenic engineering) At 1 ATM, water boils at 100C. If I lower the pressure, water boils at lower temperature. That's why it is hard to cook something in the high elevation since Pressure is too low. If liquid N2 is pumped out of pressurized container, it stays as a liquid if stored in a insulated container(since cold). That's how I ship speciment overnight....... I get your point..... If N2 is heated up, it will boil and becomes a gases state. It has a very low boiling point. That's why it stays as a gas at 1 atm........ at 25C. I should have thought about more about it..... BTW how does water cooler works?

Tim

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[This message has been edited by Tim Lee (edited 08-08-99).]

 

[Mr_Bond]

Howdy there,
I was considering building a water cooling system for my comp.
As far as I know they work similar to your car radiator, using water as the means of extending the surface area of a heat sink.

The one I was going to build would use a custom heat sink which has a thin winding tube made of copper or (ideally) aluminum which zigzag's across the chip surface. Then using a modified Oil cooler have the water pumped through the whole lot with a wind screen wiper pump, with 4 heavy duty (200 mm)cooling fans drawing air past the oil cooler radiator.
Some thing along those lines.

Hope that's helpful in any way.

 

[JF]

It will work. I have used nitrous oxide. The only problem that I have come across and am still working on is trying to recycle it after it phase changes into a gas. I need a compressor that will compress it back into a liquid for reuse. I am also looking into using CO2. CO2 has a higher expansion rate so it would use less. I have not yet put this on a cpu cause 10lbs of N2O will only last for about an hour, but the cold side of the heatsink/box I made gets -127F. I have no doubt that it would work. I have gotten a test bench that supplies 243F heat to a alum plate. Test probe placed inside the plate via drilled hole in end of plate. Plate gets to -83F when N2O is turned on. after going through 50lbs of N2O for testing I am waiting for a way to recycle it now. I am looking for a compressor now. Has to be a compressor and not a pump. If anyone has any ideas for a compressor plz post here. Thanks

 

[ducttape]

Another big problem with that is condensation. Water's going to form on it and you've got to have a way to keep it away from your components.

 

[jigsta]

water wouldn;t really be all that big of a problem. look at JF's temps. at that temp, the water will almost go from a gas to a solid instantly. also, wter formed from condensation isn;t inherently bad for your components. when the water condenses, it is PURE water. and PURE water doesn;t conduct electricity. it has to have impurities in it. fresh water is a terrible conductor, but add a little salt and it conducts beautifully. i don;t think there is too much salt in your box, but there is dust and some other crap. that other crap would take a while to affect the water enough for it to become conductive. and by the time that would happen... it would be ice.

hmmm... that's a bit long... sorry.

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da jig isz up...

 

[diablovision]

I read of a guy who used liquid mineral oil cooled to -40C and immersed his entire system in it, mainboard, cards, and all. He overclocked from a 300mhz k6-2 to 500mhz. Condensation wasn't a problem because the entire system (excluding peripherals like cdrom and floppy) were immersed.
Mineral oil does not conduct electricity at all, so screwing things up was not a problem. He used a modified air conditioner with the cooling coils submersed in the solution in order to reach -40C. No pumps are required and he even left the fan on the CPU running to help circulate the solution to the processor.
The good part about doing this is that it also cools all your cards, too, so if you have a V3 3000 that has hit its overclocking limit due to heat, you can even bump it up as well.
This is perhaps going a bit far, but hell, if you are willing to use liquid nitrogen...
It makes swapping cards a bit difficult, though! The drawback is getting oil all over the electronics, making it a huge pain in the ass if you ever want to go back to normal cooling.

If I were to build a liquid cooled system, I would use mineral oil and supercool it to -40C with a modified freezer unit and use an aquarium pump to pump it through a custom made hollow heatsink attached to the processor. That would be the easiest thing to do.

 

[Kahuna]

....hahaha, kinda extreme but to each his own.

 

[Ronin]

Liquid Nitrogen is at minus 200 degrees C. It would definetly make an ice ball around anything it makes cold. But thats ok while the condensation is ice. When it warms up, that's trouble.

With a LN2 heat exchanger it would be possible to cool the CPU for long periods of time. You would just need to keep filling the system with LN2. LN2 is also a liquid at standard pressure so you could dunk your CPU in it and then fire it up. (Not recommended).

 

[ChiefDruid]

Well, liquid N2 would definately be one of the coldest ways to cool your CPU, but you run the risk of shattering your processor due to rapid changes in temp. It would have to be carefully regulated to give a slow change in temperature. Also, condensation could be a problem, even though like Jigsta said, condensation is PURE water, and pure water doesn't conduct electricity well. If ANY ions are picked up by the water (from a copper heat exchanger, tin contacts, lead soldier, etc) conductivity goes up. My suggestion would be watercooling in conjunction with a peltier. You can attain extremely low temps. Of course there is always a possibility of leaks, but if you put some forethought into your design it's a pretty safe way to cool your cpu.

Sorry if that whole thing seems a little fragmented. Haven't had much sleep today...heheh

Hope that helps,
Shane

 

[diablovision]

I'm still a proponent of using Mineral oil as a coolant as it is completely non-conductive (eliminating the need to worry about leaks), and also (I'm pretty sure) has a higher specific heat than water, so it can absorb more energy degree for degree. Also, it won't freeze, so, like I said, you can cool it to below freezing temperatures and it still works nice.
Liquid N2, IMO, is still a ridiculous idea for a home user. For a university research team, that's another story.
The point is you have nothing to do with the N2 once it has done its cooling. It has to absorb heat, so it would evaporate, and then you've got N2 gas pouring out of your system (wouldn't that be cooling looking though!). Of course N2 isn't toxic (air is 80% n2 by volume), but if you aren't in a well ventilated area, that may become 95% or higher N2, and you slip peacefully off into dreamland as you slowly die of oxygen depletion. Now is that a worse case scenario or what?

 

[JF]

Nitrous oxide(N2O), Carbon dioxide (CO2)
1. Enclose a heatsink in a box.
2. 1 inlet, 1 outlet
3. .014 in inlet fitting for big pressure drop into box
4. Wrap box with wetsuit material except where cpu touches
5. connect line from main bottle to inlet fitting
6. connect a line to outlet fitting going to outside a window in your home
7. turn bottle on
8. box will now be frozen (from the phase change from liquid to vapor) as long as the N2O or CO2 goes through it.
9. the vapor that carries the heat will exit out outlet hose venting to the outside
10. Now recycle it!!!! where I stand now I have ways to do it, just not as simple as finding a compressor
1 10LB. bottle of N2O lasts for about 45min of continuos use in this loss system.
N2, N2O, and CO2 all will work. They all just have different boiling points, different critical pressures, different critical temps. ANY QUESTIONS????

 

[JF]

NO more questions???? Guess i scared you all away...

 

[Rogue Gunman]

Carbon dioxide has no liquid form. At high enough temperature and low enough pressure it sublimates, that is, it changes directly from a solid (dry ice) to a gaseous form. To build a refrigeration unit you need a non-acidic and non-flammable gas such as chloroflouromethane (R-22) or tetraflouroethane (R-134A) that will liquify at a suitable pressure in a condenser and give you the temperature drop you need across an expansion orfice. The refrigerant must be molecularly compatibile with the oil used to lubricate the internal components of the compressor. This assures a stable and long lasting refrigeration unit.

 

[Geoff]

You're asking for trouble if you use liquid nitrogen. Dunk a CPU in it (which is effectively what happens when you first turn the system on) and the rapid temperature change could shatter the CPU, or at least cause internal stresses that will weaken the CPU over time.

Immersing the whole computer in mineral oil is just crazy, I've seen that example and if he EVER wanted to move his computer he'd be fucked. I regularly move mine around for LAN games and such so that sort of thing isn't an option. The only possibility for me if air wasn't enough would be some kind of water cooling. If necessary I could carry the reservoir and pump around and fill it up once I got to my destination. but I don't need the speed that badly

 

[rockinwy]

my water cooler worked well kept the cpu at room temp no condensation no leaks, I did try mineral oil instead of water and the pump wouldnt pump the thicker oil with enough volume to keep the heatsink cool. building a water cooler is simply a matter of enclosing your heatsink and putting connectors on for tubing, I used on in and two out that way the pressure inside the cooler is less and so are the chances for leaks. I used a vantek slot 1 cooler which is shaped perfectly because the center fins over the cpu slug are shorter than the outside ones so all I had to do is take some abs plastic screw it to the heatsink, screws wedge between the fins and seal is up with epoxy drill on hole on one end and two holes on the other for the tubing connectors and that was it. I have a cel 400 that wont run at 500 with a standard heatsink with the water and the peltier that I am currently using it is perfectly stable. I was hoping the peltier would get me to 600 but it didnt. The peltier introduced a whole new set of problems. as long as you make sure you seal the cooler well I recomend using one, less case heat, lower cpu temp, what more can you ask for. I think mineral oil would work you just have to have a pump capable of pumping it. I used a small aquarium pump and it doesnt build enough pressure to pump through the small tubing I was using.

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[Baloneyflaps]

You guys are insane!

 

[JF]

1. Liquid nitrogen is to cold to use, unless done correctly.
2. CO2 is in a liquid form when under pressure. As it drops in pressure it phase changes into a vapor. As it phase changes it expands rapidly and gets very cold.
3. Water coolers and peltiers are great I agree. But they cannot get my cpu below -70F

4. If you type "heat transfer" into yahoo, you will find a company that makes a liquid that can be chilled to lower temps without freezing.

I use N2O on cars to make them faster and I WILL use it on my puter to make it faster!!!!!!!!