The most efficient way of watercooling?

[jaydee]

I just noticed this was a poll. Anyway I am refusing to vote simply because I don't know the answer even though I have done it. From my experience the die area is to small. The heat is to concentrated and not enough surface area for water to absorb the heat. Especially with waters low thermal conductivity. Copper spreads the heat out so water has more surface area to pick it up. The only way I can figure to make direct die more efficient is simply more flow.

Much like a radiator. The faster you can push water through it the more heat it will dissipate. Problem is the faster you make the water go the more heat gets added into the water by friction and the faster pump.

Until I see irrefutable evidence I have to go with my experience and say a good water block will beat out direct die cooling. I can't say for 100% sure though.

[bigben2k]

I gotta agree with you there; especially with today's higher than ever heatloads, I don't see it being practical at all. WB gets my vote; something's gotta spread the heat first.

[MadHacker]

Originally Posted by bigben2k

something's gotta spread the heat first.

what if you remove the heat before it spreads out?
that is what direct die will do i think

[jaydee]

Originally Posted by MadHacker

what if you remove the heat before it spreads out?
that is what direct die will do i think

Already covered it. Water won't pick the heat up fast enough.

[MadHacker]

Originally Posted by jaydee116

Already covered it. Water won't pick the heat up fast enough.

But that was a comparison with thermal conductivity of stationary copper vs. thermal conductivity of stationary water.
Granted water's thermal conductivity is very low but the water is moving.
How does that affect the math? Not that I'd begin to understand the math :shrug:

[jaydee]

Originally Posted by MadHacker

But that was a comparison with thermal conductivity of stationary copper vs. thermal conductivity of stationary water.
Granted water's thermal conductivity is very low but the water is moving.
How does that affect the math? Not that I'd begin to understand the math :shrug:

Doesn't matter if it is moving or not.

[MadHacker]

Originally Posted by jaydee116

Doesn't matter if it is moving or not.

If that was the case then it wouldn't matter if air was moving or not...
Using that consept I can remove all the fans out of my pc and have it just as cool... NOT...

I believe that moving water will remove heat faster then a non moving piece of copper.
Unfortuatly I have no proof...
and don't have the math background to create one.

[killernoodle]

The Storm doesnt rely on the spreading properties of copper, and look at its performance. The thinner the baseplate, the better. Swiftech blocks rely on spreading the heat laterally and then transferring it, thus they have thicker baseplates but are very effecient as well. There is a trade off somewhere...

[Kobuchi]

Originally Posted by killernoodle

There is a trade off somewhere...

Determined by the concentration of tubulance, I think. As focal turbulance increases, resistance increases more. That widening gap keeps us from extremes.

[Cathar]

Originally Posted by killernoodle

The Storm doesnt rely on the spreading properties of copper, and look at its performance. The thinner the baseplate, the better.

Not quite true. Storm does indeed need and make use of a certain amount of the lateral thermal spread properties of copper - not quite to the extent of the thicker base-plate blocks, granted, but it's definitely not a case of "thinner = better", that is only true with tremendously powerful pumps.

[jaydee]

Originally Posted by MadHacker

If that was the case then it wouldn't matter if air was moving or not...
Using that consept I can remove all the fans out of my pc and have it just as cool... NOT...

I believe that moving water will remove heat faster then a non moving piece of copper.
Unfortuatly I have no proof...
and don't have the math background to create one.

Not what I ment. The thermal conductivity stays the same when the water is moving or not. As I said before you need to make the water go a hell of a lot faster to make up for the lack of surface area. Problem with that is faster the water goes the higher the secondary heat sources get making it a near waste of time.

Needs more surface area OR a lot faster water. Only way to make it worth while is to chill the faster water.

Anyway, if your that interestred then do it and prove us wrong.

[MadHacker]

Originally Posted by jaydee116

Anyway, if your that interestred then do it and prove us wrong.

as i mentioned i don't have the math background to prove it..
then again i'm missing a lot of background information on the whole subject...
I'm not saying your wrong... I just like to be proven wrong...
saying I'm wrong doesn't cut it for me sorry...

[superart]

What if we used water with nano particles of thermaly conductive metal suspended in it.

That would increase the thermal conductivity, while keeping the advantage of movement and greater deltaT.

[BillA]

done, patents awarded
copper microspheres, adjust for desired sg
not commercially available

[superart]

If you were being sarcastic, don't be.
Theres actually a professor in Canada (not pH, some frenchie) working on just that, with great success.

http://forums.procooling.com/vbb/showthread.php?t=10871

[BillA]

was not, google it
I tried to buy some, not available
been there

[superart]

any indications on when/if it might be available?

[BillA]

nope
10 char

[Althornin]

Originally Posted by MadHacker

If that was the case then it wouldn't matter if air was moving or not...
Using that consept I can remove all the fans out of my pc and have it just as cool... NOT...

I believe that moving water will remove heat faster then a non moving piece of copper.
Unfortuatly I have no proof...
and don't have the math background to create one.

Well, point one:
Wrong. Air's thermal conductivity is not changing just because it is moving -neither does water. But you have to have airflow or water flow, or the water/air around your heatsink/waterblock will continue to heat up. The thermal energy transfered is a function of the difference in temperatures between the two.

[jaydee]

Originally Posted by MadHacker

as i mentioned i don't have the math background to prove it..
then again i'm missing a lot of background information on the whole subject...
I'm not saying your wrong... I just like to be proven wrong...
saying I'm wrong doesn't cut it for me sorry...

Same here. I have done it but my experiemnts are far from scientific. I had a reasonably decent direct die cooler with jets and it couldn't beat out a Maze 4. That was also with a HydroThruster 500 pump.

I got all my parts (I think) to do the project over again. I can reset it up. Will have to search for the direct die block. Somewhere around here...

[MadHacker]

Originally Posted by Althornin

Well, point one:
Wrong. Air's thermal conductivity is not changing just because it is moving -neither does water. But you have to have airflow or water flow, or the water/air around your heatsink/waterblock will continue to heat up. The thermal energy transfered is a function of the difference in temperatures between the two.

but if i had a solid block of water(ice) to apply heat to one side to raise the temperature from -20 deg to -10 to the other side...
it would take a long time... how to measure the time or the amount of heat involved is unknown to me...
but using the same volume of water(not solid but fluid) applying heat to one side the oposite side would get a fater increase in temperature because the heated water can move... while ice can't...

or is it a case that water (fluid) is close to but not quite as efficient of removing heat directly from a core as copper(solid) is and if the water was frozen it would have absolutly terrible toi remove heat?

[MadHacker]

Originally Posted by jaydee116

Same here. I have done it but my experiemnts are far from scientific. I had a reasonably decent direct die cooler with jets and it couldn't beat out a Maze 4. That was also with a HydroThruster 500 pump.

I got all my parts (I think) to do the project over again. I can reset it up. Will have to search for the direct die block. Somewhere around here...

it would be interesting to see some actual temperatures but if it is too much work...
my existance can go on without know the exact answer...

[jaydee]

Originally Posted by MadHacker

or is it a case that water (fluid) is close to but not quite as efficient of removing heat directly from a core as copper(solid) is and if the water was frozen it would have absolutly terrible toi remove heat?

It is not even close to. Waters thermal conducticity is .6 while coppers is 390. Yes that is a point in front of that 6!

http://www.hukseflux.com/thermal%20c...ty/thermal.htm

[jaydee]

If I can find the block I can rehook it up. Not a big deal at all. I have a feeling the block is were I had my mill which is 120miles one way at my grandparents place. If that is the case I will pick it up during Christmas and bring it back.

I still never got around ot making the second block for the Chip bretb sent me. I got it sitting here with a 75% done block but I think I got to change it all.

[Cathar]

Volenti is perhaps the most successful person I've seen with a direct die setup using a set of high-speed jets. Using a fairly meaty pump (MD-20RZ) he was able to get it to roughly perform on par with his old White Water clone that he made up himself, but this was also on a P4 die (~147mm^2).

I have a feeling that an extremely well setup direct die setup can come close to a top-end enclosed water-block, but it requires the use of fairly strong pumps to generate the jet velocities required to over-come the surface area disadvantage.

Really this is what it comes down to. Enclosed waterblocks have the TIM + conduction cost but make up for it with increased surface area. Direct-die doesn't have the TIM + conduction cost, but will typically have 1/2 the convectional surface area available.

It's a case of 6 of one and half-dozen of the other. Jet impingement on such a small scale is highly dependent upon jet velocity, and hence the pumping power. This is an issue that I tried hard to solve with the Storm blocks, but none of the performance enhancing features of the Storm blocks would be available in a bare die.

My best answer is that "maybe direct die could be as good as an enclosed waterblock, but my feeling is that it will fall somewhat short". Direct-die waterblocks come with the added hassle of being more difficult to setup and maintain without dripping water over the inside of the computer. Since CPU's are not water-proof either it becomes even more of an undesirable cause to attempt to prove because the CPU will die anyway.

Given the drawbacks and the evidence which suggests that at best direct die cooling is still somewhat behind the current top-end waterblocks, and at worst a long way behind, this hardly instils me with a lot of faith that it's something worth pursuing. This makes the answer just pure theoretical conjecture in the mean-time until someone proves otherwise, and right now the limited experiments and theory available tell us that enclosed waterblocks are superior for performance, as well as for practicality (and also for lack of CPU death).