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Passive water cooling

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joshhua5

Member
Joined
Jan 29, 2010
hello i'm planning cooling for a future rig

what my aim is the most silent passive water cooled computer

would this work the case would be somthing like this but not the same somthing bigger (i can't find the one i sore before)
http://www.directron.com/vf6000bws.html

and have water cooling / cpu blocks to everything
coming up to 3x4 radiators /w no fan and 3 small low db pumps per radiator

from 1 radiator to the pump from there to another radiator then another pump and radiator and back into the blocks all possitioned on the top

rubber pands and screwes for pumps

(price isnt a limit and don't worry about parts but there will be a mobo cpu ram gpu psu to be cooled)
 
I don't see how you're going to get the heat transfered from the water with the system you described...though it's late(early) and I am feeling very...special. I use a passive cooling system on my main rig, though only the CPU is on water. I simply pump water to and from a 25 gallon tank. No radiatiors or fans on the water loop at all. By the end of a hot summer day of encoding or rendering the water temp is 10c warmer. Well 15c warmer with i7. I've toyed with the idea of building a decent sized bong cooler and running a loop from the reservoir to the bong and back again to cool the water...someday maybe. :)
 
The heat is disappated by airflow though. Radiator surface area will drop the temps a bit, but not enough and that heat will just go right back through the loop.
 
ok what about this

a box with only a 2mm gap fom top and bottom on the top there's heat fins the the water goes in through (im making a paint picture to show that i mean)

EDIT:


my insane technical drawing
 
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As TimoneX posted, the heat needs to be pulled or pushed away from the rad in order for it to be effective.

Over time it will be useless as there's nothing drawing the heat away from the rad. Eventually the heat will be dumped back into the loop.

You do know there's a watercooling section? Plz post in appropriate section.
 
Imagine your going to have a bath. If you turn on the hot tap one end will get hot quickly. If you stir the water around then the whole bath will be evenly warmed.
The same is true with watercooling except all the water won't cool down over time.

Thinking about it it could be possible to create a pressure system to get this to work but it's way to complicated and the CPU temps would have to be up at about 200 degrees to make it viable.
 
No, but there is another option: Have you ever dug a hole and the deeper you dug the cooler the dirt was?

One member here buried a huge rad made of pipes about 12-15feet deep into the ground then ran insulated copper lines into the house thru the wall.

He used a massive AC pump with a huge res. He has something like 5 computers hooked up in series all watercooled with this one massive apparatus.
 
No, but there is another option: Have you ever dug a hole and the deeper you dug the cooler the dirt was?

One member here buried a huge rad made of pipes about 12-15feet deep into the ground then ran insulated copper lines into the house thru the wall.

He used a massive AC pump with a huge res. He has something like 5 computers hooked up in series all watercooled with this one massive apparatus.

WOAH! Seriously? You'll have to have some seriously powerfull pumps to bring it up 15 feet :D
 
Yes, a passive system CAN work if the heat load isn't too high for the radiator area being used. Here's an interesting thread you might want to look through: http://www.overclockers.com/forums/showthread.php?t=429836

WOAH! Seriously? You'll have to have some seriously powerfull pumps to bring it up 15 feet :D
It doesn't have to "bring it up 15 feet" - it's a closed system. You're thinking of an open system like a well, closed systems don't work that way. There is no "height" anywhere inside a closed loop, it's all "flat" from that perspective. Somewhere around this forum there's even a video of someone with a loop hanging to the ground out their 2nd story window and all they're using is a small Eheim (I think) fountain pump to move water through the loop. The only resistance our loops have to overcome is the resistance of the tubing/pipes and the pressure drop through the components, including their fittings.

No, but there is another option: Have you ever dug a hole and the deeper you dug the cooler the dirt was?

One member here buried a huge rad made of pipes about 12-15feet deep into the ground then ran insulated copper lines into the house thru the wall.

He used a massive AC pump with a huge res. He has something like 5 computers hooked up in series all watercooled with this one massive apparatus.
Sounds like my idea of heaven and if I had a Bobcat I could borrow I would have already done it! Of course, the pipes don't need to be that deep. IIRC, 5-6' down on flat ground temps are pretty stable at 55-60°C, depending on where you live ...
 
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It doesn't have to "bring it up 15 feet" - it's a closed system. You're thinking of an open system like a well, closed systems don't work that way. There is no "height" anywhere inside a closed loop, it's all "flat" from that perspective. Somewhere around this forum there's even a video of someone with a loop hanging to the ground out their 2nd story window and all they're using is a small Eheim (I think) fountain pump to move water through the loop. The only resistance our loops have to overcome is the resistance of the tubing/pipes and the pressure drop through the components, including their fittings.

I'm sure there's a law against you moving water greater than a certain height though. The closer you get to that point the harder it is to move that water.
This might not be true in a closed system but I don't know enough to comment I guess :p
 
I'm sure there's a law against you moving water greater than a certain height though. The closer you get to that point the harder it is to move that water.
This might not be true in a closed system but I don't know enough to comment I guess :p
Not as long as it's a closed loop so there is no height OR if you have an open loop (more than one opening) with all openings at the same height and higher than the rest of the loop.

Try this very simple experiment - even if it's just a "mind-thought" experiment. Take the longest piece of tubing you can find, or think of. Hold both ends of the tubing at the same height while keeping the rest of the tubing below the openings and, hopefully, unkinked so you have a big, long 'U'. Now pour water in the tube opening on the right side. As you fill the tube the water level on both sides will remain the same. Now you have to ask yourself: How did the water in the right side of the tube get into the left side of the tube? If you add more water to the right side, the left side will even out again. So how does the water get there? It's a simple tube - no pump at all!

It's a small step from that experiment to closing the loop by putting the two ends into a pump inlet and outlet then turning the pump on to circulate the water. You can even add a 'T' into the loop because the water in the upper part of the 'T' isn't part of the loop - it's a dead end. BUT, don't put a hole anywhere else in the loop! If you have two holes at different levels (heights) then you have made it an open loop and gravity comes into play ...
 
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tinymouse2, nope, the only limitation is overcoming line resistance. Basic physics here.

A closed loop system is just that, closed. It doesn't matter if the loop is horizontal or vertical since the pressure is equalized on both sides of the pump. All the pump has to do is to overcome the physical resistance to movement to circulate the fluid, unless you are using a non-newtonian fluid. And since we generally try to go with just plain water with minute amounts of additives for anti-microbial and anti-fungal protection, the fluid is a newtonian fluid in our loops. A non-newtonian fluid requires extra pressure to start the fluid column moving, but that's not a problem with our systems.
 
I did mine passive, used a nissan truck radiator. With no fans on it at all the water temp was ~8*c above ambient air temp.
With a single 120mm fan on it (looked mighty silly) the water temp was ~3*c above ambient.
That was with a ~48w load, [email protected] 1.32vcore.

With a 1000cfm box fan on it, the water was essentially at air temp :p
 
Not as long as it's a closed loop so there is no height OR if you have an open loop (more than one opening) with all openings at the same height and higher than the rest of the loop.

Try this very simple experiment - even if it's just a "mind-thought" experiment. Take the longest piece of tubing you can find, or think of. Hold both ends of the tubing at the same height while keeping the rest of the tubing below the openings and, hopefully, unkinked so you have a big, long 'U'. Now pour water in the tube opening on the right side. As you fill the tube the water level on both sides will remain the same. Now you have to ask yourself: How did the water in the right side of the tube get into the left side of the tube? If you add more water to the right side, the left side will even out again. So how does the water get there? It's a simple tube - no pump at all!

It's a small step from that experiment to closing the loop by putting the two ends into a pump inlet and outlet then turning the pump on to circulate the water. You can even add a 'T' into the loop because the water in the upper part of the 'T' isn't part of the loop - it's a dead end. BUT, don't put a hole anywhere else in the loop! If you have two holes at different levels (heights) then you have made it an open loop and gravity comes into play ...


tinymouse2, nope, the only limitation is overcoming line resistance. Basic physics here.

A closed loop system is just that, closed. It doesn't matter if the loop is horizontal or vertical since the pressure is equalized on both sides of the pump. All the pump has to do is to overcome the physical resistance to movement to circulate the fluid, unless you are using a non-newtonian fluid. And since we generally try to go with just plain water with minute amounts of additives for anti-microbial and anti-fungal protection, the fluid is a newtonian fluid in our loops. A non-newtonian fluid requires extra pressure to start the fluid column moving, but that's not a problem with our systems.

It's kinda obvious when I think about it :D
Should probably think harder before posting I guess.
 
To the OP: By "passive", do you mean without a water pump?

I think you really need to push water through the loop. I can see passive in the sense of no fans. If you allow for convection, warmer air rises and cooler air sinks, you could design a system that will passively move air and thus cool the system.
 
It's kinda obvious when I think about it :D
Should probably think harder before posting I guess.
Don't feel bad - a LOT of people don't get it unless it's pointed out. I'll tell you the idea I had trouble with - wrapping my head around the fact that the open end of the T could be below the top of the loop! Pretty obvious in hind-sight after I read it but not so obvious up front ... ;)
 
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