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Startup's Submerged Servers Could Cut Cooling Costs
1sockchuck writes "Are data center operators ready to abandon hot and cold aisles and submerge their servers? An Austin startup says its liquid cooling enclosure can cool high-density server installations for a fraction of the cost of air cooling in traditional data centers. Submersion cooling using mineral oil isn't new, dating back to the use of Fluorinert in the Cray 2. The new startup, Green Revolution Cooling, says its first installation will be at the Texas Advanced Computing Center (also home to the Ranger supercomputer). The company launched at SC09 along with a competing liquid cooling play, the Iceotope cooling bags."
..computers, allow me to label this a "fad"
The idea is funky, but to get good cooling you want convection (every joule of pump energy from a circulating pump gets transferred into the oil at yet more heat) which means deep tanks which means, to the server environment, goodbye high density.
The ONLY thing that has changed since I was doing this is the affordability of SSDs, which mean that now it is practical to immerse the whole computer, and the mass storage too, which makes things a lot simpler and cheaper, and means you really can be JUST oil cooled, not oil cooled mainly, except for air cooled HDs etc.
TOP TIP from an old hand.
If you are going to oil cool by immersion, buy the latest top quality hardware, because once immersed it stays there, you'll only pull it once to see why it sucks.
BIGGEST mistake experimenters make is using old hardware, cos you always end up playing with it, making mess, ahh fsckit..
Nota Bene if you are building one of these in anger, make allowances for the significant increase in the weight that the oil makes.
HTH etc
http://slashdot.org/~GuyFawkes/journal
In the embedded video, they indicate that hard disks need to be wrapped in some material the vendor apparently provides, presumably for just this reason. Not sure how well the wrapping transfers heat.
Educate thyself: http://en.wikipedia.org/wiki/Mineral_oil#Mechanical.2C_electrical_and_industrial
Just because something CAN burn doesn't make it dangerous to have around potential sources of electrical arcing. Hydrocarbon petroleum products present no real fire/explosion danger unless the substance is warmer than its flash point, which is the temperature above which the liquid substance can evaporate into the air. Below the flash point temperature, oil is only as flammable as plastic. The evaporated fumes mixed into the air are the ignition danger, not the liquid itself.
This is because ongoing hydrocarbon combustion requires steady supplies of freely-mixing HC and oxygen. Sustaining the reaction requires the input of a tremendous volume of oxygen (compared the the liquid fuel volume, anyway), and the oxygen has to get rapidly mixed with the HC. That mixing can't happen quickly enough to the liquid HC. That's why the flash point is such an important consideration--the gaseous HC fumes mix quite well and quickly with atmospheric oxygen, creating nice conditions for a sustained combustion (a fire).
This is even true of gasoline (flash point = -40F). If you pour gasoline into a pail in the middle of a bad Antarctic winter, and you throw a match into the pail, the gasoline will just extinguish the match like a bucket of water.
Of course, if you mix liquid HC with liquid oxygen, or any other eager oxidizers, all bets are off. That shit will explode at cryogenic temperatures if you just look at it funny. (That's how rocket engines work.)