different idea

Modder man

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have any of you ever thought of setting up a loop like a watercooling loop as far as block and lines. but then hooking up a co2 tank to it
 

peanutskeeter

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You mean LN2 lol? I have never heard of carbon dioxide cooling a computer but I guess it's possible. I think when you enclose LN2 it becomes explosive. So if it were air tight inside of a water loop it would explode. That's why whenever you see LN2 setups there is always room for air to dissipate the evaporating LN2.
 

Modder man

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no i did not mean ln2, in a gas state co2 is very cold, so it would go thru the loop and just be vented off on the other end
 

Modder man

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im not entirely sure how to set it up....nor do i have the tools to make the block
 

EricFX1984

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honestly there are simpler options out there that are already tried and true. that being said it's still a neat idea :p
 

Modder man

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doing something that everyone does is not very challenging, and takes half the fun out
 

vengence

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A bit of a thread necro, but I'll try to add a little insight to make it worth the necro. Will probably fail though.

Without phase change, the limit of your cooling capabilities is the ambient air temperature. If you had a magical block that sucked all the heat out of the CPU, as fast as it got there with no delta T you'd still be limited by the ambient air.

Of course, there aren't magical blocks, and we are limited to reality. Water cooling approches the real world limits. Take for example a Koolance CPU-360, one of the top blocks in water cooling (not the king, but good). Doesn't matter how many radiators you put on it, you're still limiting at the water block. Infact, even turning up the flow doesn't help that much. What that means is, you are required to increase so much in temperature to overcome the thermal resistance.

You could in theory use something like mercury perhaps to gain an extra degree, maybe two out of a liquid loop, however you are still limited by ambient temperature.

There are two main ways to get around this boundary. The first is thermo-electric devices such as peltair blocks. However, these are extremely power hungry, but they do scale. If you are willing to pay 1500W move 200W of CPU heat you can, and will have a very nice system. However, your cooling system now has to move 1700W of heat to the outside of your case and you'll need a power supply capable of moving 1500W. But you would be at -100C or so.

Alternatively, you can use phase change cooling. Compress a gas and it's temperature rises, pass it through a radiator to cool the gas back to ambient temperature. Then pass it through an evaporator where it expands to and drops it's temperature. This drop is how you get sub ambient phase change cooling. It is much more effeicent than peltier blocks, however the inital cost is much more. Compressers and such aren't cheap. The old vapor chil units were 1Kish in price IIRC.

Dice, LN2, LHe2, etc all use cold objects as sinks. LN2 is very cold, and absorbs large amounts of energy as it phase changes to a gas. However, the LN2 is not captured and converted back to a liquid by a compressor. If you want a true "extreme" long term system, that would be required. Although if I went through all the expense (thousands of dollars) to do that, I'd probably build a liquid helium system. But then again, water cooled SR-2 with dual 6 core Xeons starts looking cheap by comparision. And very few people have both problems and money to go beyond a WC SR-2 setup.
 

Modder man

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the thing is co2 in a gas state is very cold thus giving a similar effect of dice or ln2. the advantage being if it is run in somewhat of a loop is that you will not have to refill all the time and the temp will stay constant
 

vengence

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the thing is co2 in a gas state is very cold thus giving a similar effect of dice or ln2. the advantage being if it is run in somewhat of a loop is that you will not have to refill all the time and the temp will stay constant

:confused: CO2 is not cold in a gas state. It's part of the make up of air. In fact you create it when you breath out. Dice is solid CO2. There's no magic with CO2, it heats up just like anything else.
 

Necere

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:confused: CO2 is not cold in a gas state. It's part of the make up of air. In fact you create it when you breath out. Dice is solid CO2. There's no magic with CO2, it heats up just like anything else.

Correct. It takes energy to remove heat from things (at a rate faster than natural convection/conduction etc.). Liquid/solid CO2 is cold, but because a lot of energy has gone into removing the heat from it. Using it to remove heat from something (e.g., a CPU) is going to heat it up. Then you'll need to either add fresh coolant, or use energy to remove that heat on the spot (i.e., a compressor/phase-change system). Keep in mind that all energy decays to heat, so the more you use, the more heat you have to move to the ambient air. In other words, a phase change system will heat up a room more than a water cooling loop, which may heat up a room more than basic air cooling (depending on number/type of fans, pumps, electrical efficiency variance due to temperature etc.).

Attempting to use any gas as a coolant in a water cooling loop is an exceptionally poor idea, as its density precludes it from having much in the way of heat conductivity or capacity. Also, how do you expect to pump it? You want a liquid coolant.
 

Modder man

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why would you need to pump it, welders do not use pumps the gas is compressed so tight in the cylinders no pump is needed
 

Necere

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When you said "you will not have to refill all the time" that implies to me that you've got the coolant circulating somehow. If you're just hooking up a tank and using the tank pressure to move it through the line then you'll eventually need to refill the tank.
 

MrWizard6600

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Dice, LN2, LHe2, etc all use cold objects as sinks. LN2 is very cold, and absorbs large amounts of energy as it phase changes to a gas. However, the LN2 is not captured and converted back to a liquid by a compressor. If you want a true "extreme" long term system, that would be required. Although if I went through all the expense (thousands of dollars) to do that, I'd probably build a liquid helium system. But then again, water cooled SR-2 with dual 6 core Xeons starts looking cheap by comparision. And very few people have both problems and money to go beyond a WC SR-2 setup.

LN2 isn't actually cold, its the same effect as you're compressor: grab it when its gaseous, compress it to liquid, at which point its hot, cool it off, and now you've got a pressurized substance thats at room temperature. Then instant you release it from that pressurized environment, it jumps straight back to gaseous phase, which makes it stupidly cold. Ironically it also supersaturates the air at 1atm, meaning you can actually pool the liquid if it doesn't have a huge surface area, which is exactly what those LN2 coolers are doing. Its the process of evaporation that makes LN2 cold, not the LN2 itself. Its really very similar to alcohol, just, much more potent.

What the OP is talking about is impossible. The only way to get a negative delta T (over ambient) is by trading phase for temperature (or, as vengeance suggested, peltair plates, which are crazy and I have no idea how they work except, diodes and current as heat or something), which is exactly what LN2 and Vapor-based systems are doing.

You could use CO2 in a compression -> radiator -> expansion -> CPU loop afaik, but it would be significantly more expensive than the fluid they're already using.
 

vengence

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LN2 isn't actually cold, its the same effect as you're compressor: grab it when its gaseous, compress it to liquid, at which point its hot, cool it off, and now you've got a pressurized substance thats at room temperature. Then instant you release it from that pressurized environment, it jumps straight back to gaseous phase, which makes it stupidly cold. Ironically it also supersaturates the air at 1atm, meaning you can actually pool the liquid if it doesn't have a huge surface area, which is exactly what those LN2 coolers are doing. Its the process of evaporation that makes LN2 cold, not the LN2 itself. Its really very similar to alcohol, just, much more potent.

The LN2 in liquid form is cold even in the pot. If it was simply the act of boiling that lowered the temperature, then we'd just boil water and the water would get colder and well, yeah...

LN2 coming out of the container is chilled. The phase change simply provides the energy sink, not the cooling.
 

MrWizard6600

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The LN2 in liquid form is cold even in the pot. If it was simply the act of boiling that lowered the temperature, then we'd just boil water and the water would get colder and well, yeah...

LN2 coming out of the container is chilled. The phase change simply provides the energy sink, not the cooling.

The "energy sink" is cooling by definition. LN2 is not "cold" in liquid form by necessity, its just pressurized, you can heat it just like you can heat any other substance (keeping in mind, it is pressurized, and with every 10C you're going to exponentially increase the pressure, meaning if you take a pressurized LN2 tank and hold it against a heat source for long enough and it'll explode).

Cooling is to an energy sink what an electron is to an electric field. We really dont have any way of finding out exactly where charge by finding its mass, we can only infer based on the reaction of space around it.

keep in mind Liquid nitrogen is not an insulator. Meaning when the surface undergoes evaporation that thermal transfer is (after some time delta) transferred ubiquitously across the substance (and any substance in contact with with it (the copper), and in the case of the CPU, the IHS).

Its all just trading entropy (S, where S ∝ pressure, or rather saturation of medium) for enthalpy (H, where H ∝ temp) some weighted sum of the two creates a constant (like momentum). The entropy level for water in gaseous state requires that if contain a HS constant (typically called "G") of lets say 3, where 0 is water at room temperature, and 3 is water vapor at room temperature and/or liquid water at 100C. To bring it up to that constant you have to boil it. Once you do get it to 3, because the system is vented, it changes phase rather than continue to increase in temperature, because thats easier for it to do. Thus, the reason you dont get cooling is because you were dumping enthalpy into the system in the first place, it was your direct action that cause that increased G constant in the first place. In the case of LN2, its already in that constant, your just putting it in a system where the medium is totally unsaturated, so it makes sense for a (dramatic) shift toward entropy, and since G is constant, that results in a (dramatic) shift away from enthalpy --> cooling.
 
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