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Submerged mineral oil PC - but EE what would say on it? Finally...
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dmills:
note that those specific heat numbers are per gram, you need a lot fewer litres/second of oil for a given delta T then you do air, because the oils are far more dense.
The difference is far more then the specific heat numbers on their own would imply.

I would not bother for a computer, but am thinking about a water loop for an RF power amplifier, the power density of modern LDMOS sand makes cooling painful (1,500W in a few square cm).

73 Dan.
CatalinaWOW:
This double ee would say forget it.  Not because of component damage or any of those things.  It will probably work fine for quite a while.  But the cool factor is small, the trouble factor is big.  It is now heavy, has to be right side up, is a royal PITA to service, and doesn't buy much if any on performance.

If you want cool, set up a CO2 tank to periodically spray dry ice on the machine, or set up a LN2 spritzer.  (be very careful if you do this.  It isn't that hard to kill yourself by suffocation.  Frostbite also sucks, and too much spritzing will kill your computer.)
FrankD:
Don't use skydroll or break fluid.
Berni:
Yes those heat capacity figures make air seam better than it actually is since a given volume of air at sea level has very little mass, but air does have one large advantage, its viscosity is very low. This is best demonstrated by compressed air plumbing, the tiniest of gaps result in quite a sizable air leak while if you put water at presshure in the same piping it would result in a very slow drip or no leak at all. A lot of gases even when liquefied at low temperature or high pressure maintain there very low viscosity. Liquid helium is even famous for having an incredibly low viscosity. But even water flows a lot easier than most oils.

A low viscosity not only means that its easier to push the same amount of fluid trough the heatsink using the same fan but it also makes the fluid not stick to the fin surface as much. Only the fluid that is making contact is useful so if the same fluid sticks around on the surface while the fluid above it moves then your thermal transfer is not very good. The way PC watercooling combats this is by making the fin gap inside the waterblock very narrow and use a decent amount of pressure to force liquid trough them. This makes for a high flow velocity trough the restricted path so it can drag the sticking fluid along as well as not give it much room to flow anywhere but right next to the fin surface. This also allows for a tiny heatsink size so less copper is needed to spread the heat out to a larger area (copper also has thermal resistance, even if its small)

Maybe you could get great cooling performance if you use good low thermal resistance heatsinks with high power fans in oil. Those high power server/industrial fans make hell of a racket in air but would likely run silently in oil. That way you overcome the viscosity issue with raw power, get the benefit of a smaller heatsink to reduce the path for the heat to travel and still have it silent.

But in the end of the day i think its very hard to beat a properly designed watercooling setup, if you want to go more extreme than that you can always use phase change refrigeration to cool your PC components below ambient, or even deep freeze them for huge overclocking, tho i don't think even an air conditioner compressor would be powerful enough to cool a gaming PC down deep negative and keep it there all day. Also you would need to carefully control it and regulate it as freezing CPUs too cold makes them crash and unable to boot. That is ignoring the practical challenges of needing a outdoor heat exchanger to get rid of the kilowatts of heat, keeping moisture from condensing on your components or the long term reliability concerns of running computer hardware at there very limits continuously.
james_s:
I've used mineral oil to submerge HV transformers and the stuff is a real pain. It gets *everywhere*, it's almost impossible to prevent all leaks. Anything it gets on is then virtually impossible to get adhesive or sealant to bond to. If you use wires, especially stranded wire in it the oil wicks up under the insulation. I can't imagine what possible advantage there would be to immerse the whole PC. Air cooling works just fine and can even be made very quiet. For those who just have to be different, water cooling with water blocks on specific components is viable.
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