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Aquarium Full of Oil For PC Cooling
JaredOfEuropa writes "Forget fancy watercooled CPUs or complicated heat pipes. Annoyed with the noise of the forced-air cooling in his computer, this guy simply dumped his entire motherboard in an aquarium filled with mineral oil. (coral cache). No modifications were necessary; he even left the fans running to keep the oil moving about. The only thing not submersed in oil is the hard disk."
he only thing not submersed in oil is the hard disk.
:)
And what about the CDROM drive eh, eh?!
"Hey! Unless this is a nude love-in, get the hell off my property!!"
This has been done before, as reported by slashdot almost six years ago. Of course, the guy in the '99 story used a styrofoam cooler, while the newer one upgraded to an aquarium, so I guess progress marches on!
New Headline: Slashdot effect causes need to change the oil........
Isn't a mirror kind of useless if it has to pull the images from the original site's server? Just askin'
Give a man fire, and you warm him for the night. Set a man on fire, and you warm him for the rest of his life.
The reason that you can't submerge electrical parts in water is the simple fact that water is electronically conductive given the presence of electrolytes (which is so hard to guarantee against in practice, that you can rest assured that water is bad.) Many oils, however, are not electrically conductive. Therefore, as long as the medium used is electrically inert and does not chemically react with anything you're submerging in it, you can consider it a viable medium for immersion cooling assuming that heat transfer properties are favorable.
This has been done before. Interestingly, some projects have looked to it for outdoor computer use (stationary) due to the water-repellant properties of many oils.
It makes a good laxative.
This is my sig. There are many like it but this one is mine.
I'm an elevator Engineer. This reminds me of a very old residential elevator controller I saw recently that was installed in 1917 and still had all the original equipment in good working order. The controller was in a cast iron tub with all the relays mounted to the lid and suspended in transformer oil. There was a hoist in the ceiling to enable lifting the lid for access to the relays. It would cost a fortune to build something like that today, but it certainly was durable.
"Do the Right Thing. It will gratify some people and astound the rest." - Mark Twain
Why wouldn't they? Oil doesn't conduct. That's why it's used for cooling in electrical devices such as transformers, dummy-loads and such. I recall one vendor who demonstrated the high breakdown voltage of their oil by running a TV set in a vat of the stuff. Almost anything has better heat removal ability than air and for silent running it's not a bad idea.
There is still the problem of removing the heat. If there is enough surface area to allow the heat to be removed then you are ok, otherwise the oil (and everything else) will get too hot. Encasing everything in a metal box with fins on the outside would probably keep things even cooler.
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"You are not remembered for doing what is expected of you." - Atul Chitnis
Except that the fans are still on, which supposedly moves the oil around. And when oil at the surface becomes warmer than room temperature, the heat is disappated into the air, with much greater surface area than is touching the heat source.
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Cogito cogito, ergo cogito sum.
No, you can't use water because it will become conductive when almost any substance is added to it, such as the metal flakes coming off of computer parts, other microscopic contaminents, and even carbon dioxide which will cause the pH to change. On the other hand, mineral oil is a non-conductive liquid, there are several although mineral oil is definatly the cheapest. Also, water is corrosive whereas mineral oil is not. A while back there was an article about using 3M Novec 1230 (AKA Sapphire) for submerged cooling (the poster mentioned it but forgot to take into account the low energy needed for Novec 1230 to vaporize) read the comments for more info on why water will not work. FYI somewhere in there you can find a link to pics of a guy who tried using water and fried his UPS.
If he used it as the webserver for these pictures, I would say the fire department is probably on it's way already.
Well, there's spam egg sausage and spam, that's not got much spam in it.
The guy uses vegetable oil not mineral oil according to his site.
I did this for a year or so using mineral oil, a plastic storage tub and a small dorm-sized fridge. I had a small electric pump that pumped mineral oil into tubing which was coiled inside the fridge (drilled and in and out hole on the side) and then back into the resevoir. I was a little worried about condensation but it ran fine for over a year before I got tired of the clutter and mess of it. I could have done it better but I didn't want to spend any money on it and just use what I had laying around.
It was mostly for fun with a few interesting things I learned from it:
* It allowed me to overclock about 30% more than I could previously squeeze out.
* The mineral oil did not harm the hardware at all that I can tell from a year of being submerged(it just was a pain to clean).
* If you have your resevoir higher than your mouse then your mouse will be full of oil in a few weeks (same goes for any component connected by wire I imagine).
* The only component I found that could not be submerged was a hard drive.
* The outside coating on the wires will harden and break away after being submerged long enough(but they will still work).
* There was no connection issues with PCI cards or any peripheral device that was plugged in even if they were coated in mineral oil(even jumpers could be changed while it was submerged).
* If a drop of some other liquid (that is lighter than the oil) accidently falls into the resevoir it will quickly be coated by the mineral oil and slowly fall to the bottom and can be sucked out (phew!)
Probably more but those were the most interesting things I remember of it.
pretty much. here`s the mirrordot.
Stop Computers/Cars Analogies on S
don't give up your day job for a career in heat transfer...
A large surface area (e.g., the sides and top of the acquarium) makes an efficient device for convective heat transfer to the room air. The mineral oil would certainly get warmer than the room air, but it would stay well below the temp of the PC components.
Given sufficient motivation, the steady state value can be calculated within a fraction of a degree. Lacking that motivation, however, a reasonable approximation is that the acquarium would be less than 10C above room temp.
then you could always make some killer fries by overclocking. i see no prob w/ that.
Stop Computers/Cars Analogies on S
Health Rating: 1 - Slight Flammability Rating: 1 - Slight Reactivity Rating: 0 - None Contact Rating: 1 - Slight Looks like very nice stuff to me, considering lots of common chemicals have higher hazard ratings. If you're going to link to something sophistcated like a MSDS, at least know how to properly interpret it.
Who do you get to be an expert to tell you something's not obvious? The least insightful person you can find? -J Roberts
The problem with using "very pure" water is that it wants to become impure in the worst way. It's astonishingly reactive stuff.. It will suck atoms of carbon, silicon, and copper off a motherboard in its quest to become impure. And then, at some point, it starts conducting, and you're screwed.
So, you're partially right- you could use very pure water (for a very short time) until it managed to eat enough impurities to start conducting again.
Assuming you meant water, the you're wrong. Just water is quite a good insulator.
The US Navy was using water cooled computers long ago. Just flooded all the circuit cards with distilled water.
Note that you have to do this with pure water. If you dissolve much of anything in it, then the SOLUTION begins to conduct.
Most of the water you come into daily contact with (puddles, rivers, flooded basements, even tap water) has quite a bit dissovled into it, which is why generally electricity and "water" don't mix.
I'm surprised that the PSU and all the cables (like speaker/CAT5) work at all, I feel so uneducated.
Actually, I'd be more worried about the high-speed circuits in the machine. Oil does not conduct electricity, but that doesn't mean its electronically equivalent to air.
Oil has a dielectric constant of between 2 and 3 (depends on the oil) and that will affect the capacitance on and between the traces of the circuit-board. The signals will run a little slower on the board and have a bit more cross-talk. Its probably not a big deal -- the materials in the circuit board have a bigger effect -- but it could slow the signals enough to reduce reliability in a marginal design.
Two wrongs don't make a right, but three lefts do.
wouldnt there be problems caused on the mobo due to the changes in capacitance between all the conductive tracks?
No, because the trace impedance is set by the dialectric between the layers in the motherboard - it's the dialectric constant of the PCB material combined with the spacing between the trace and the plane beneath it, along with the trace width. Whatever is above the trace, in terms of what would normally be free air, makes virtually no difference, particularly since the motherboards already have a conformal coating with a fixed dialectric constant anyway.
But there are probably plenty of other reasons why vegetable oil isn't so great for your computer.
-h-
However, This site suggests a 75 watt heater to keep a 20 gallon tank 18 degrees F above room temperature, or a 150 watt heater for 36 degrees F.
The computer probably puts out less than 150 watts total. Even assuming an 80 degree F room, that would put the computer at 116 degrees F, which wouldn't upset the computer at all. Granted, the heater you put in a fish tank has a thermostat, and so it's not on all the time, but your computer will not have any problems at 116 degrees F inside, and could go a good deal higher safely.
But I do agree with the other guy to respond to your post -- I don't see the fans even turning, let alone turning enough to move the oil around. Perhaps if they were cut down some ...
Of course, I have no idea how well heat flows through oil, or how well it's transferred from oil to the air. But I imagine that the heat generated is low enough for it to not be a problem.
Its that density that has alot to do with it: more mass for it to offload the heat into per area vs. the air. Even if the fans were left off, oil is a much more effecient conductor of heat than air. To get straight to the point, the thermal conductivity (ie: how well it conducts heat) of air is 0.024Watts per Meter*degree Kelvin, vs that of Oil (machine oil in this case, but mineral will be on the same order of magnitude) at 0.15W/MK. Water would be better if it didn't tend to let the electrons go wherever they wanted, its conductivity is 0.58. The area of hot surfaces on the computer that are exposed is the same, since this is total emersion, and so long as the oil is moving enough to distribute the heat, the ammount of oil in the container is enough to serve as a decent heat sink, and the large surface areas of the top of the oil and sides of the aquarium would be sufficient for distributing that heat for the air to convect away.
How much heat this would work for would require thermo equations on the surface area of the exposed tank surfaces using convection (q=hA(dt)). h is the thermal transfer coefficient, and depends on velocity, density, geometry, flow pattern and a few other things, and since Im lazy Ill leave that as an exercize to the reader. Once you find h though (and for a flat plate like the aquarium walls and oil/air surface is, it should be easy), calculating the saturation point is simple.
been too long since I touched thermo...
tm
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Oil isn't even necessarily the best material to do this -- it's probably just the cheapest and easiest for a hobbiest to get hold of.
Liquid Fluorocarbon does an excellent job. The Ontario Science Centre used to have a great display of an operating television completely submurged in a small vat of the stuff. And fluorocarbon is effectively a plastic itself, and thus is harmless to plastics (unlike many oils).
Yaz.
Just imagine how efficently you could carry heat away if you submerge the motherboard in mercury!
Oh wait...
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