yea that's pretty much the limit for a p4 board, the stock plastic fitting "thing" is 90mm x 75mm with another 8mm or so of extra clearance on the mobo towards the northbridge.

I made a large copper heatsink at one stage for the p4 that was 80mm x 100mm and had to cut a notch out of it to accomadate a capacitor.

Of course it increases the pressure, but I'm thinking for the same flow speed, what's the ideal channel depth?

From the link, it seems that turbulence is a factor, in that, either a) we create turbulence within a low flow rate, by adding turbulators

or

b) just go straight for a high flow rate, which in itself causes the required turbulence.

Either way, it's going to be restrictive, and will increase the backpressure (aka the pressure drop across the block).

um is this a possibility?
 

Ok i attached a file with an image. I dont have any where to put it up on the web so if sumone wants to host it just put up the file.

What i was thinking was if you had a center inlet. With a cone, that had a hole in it to the bottom and also holes in its sides, the inlet would be bigger than the cone however thus not letting all water go into the cone. The rest of the water would be sent into 4 little resevoirs where they would then be sent down mazes ending in two different outlets.



Sorry if this would not work at all im just trying something.

Me. First Reply whoppee :D

Also could sum1 please host it i feel it would be a lot easier

P.S. it would be a better pic if it was actually scaled to size, and not dun in paint(i found it quick and easy to use so i used it).

Found this thread after coming over from oc-forums and found people talking about blocks very similar in design :)

I already designed (on paper) a straight-thru block similar to the ones mentioned on the first page - Designed with maximum surface area and maximum water flow (no hard 90*, etc..). Currently designed with two rows of straight-thru holes, roughly 1/8" or so. It will be on a pelt so I assume I'll have a bit wider heat distribution than if it was sitting right on CPU core, so I'm designing the input & outputs for even flow without any stagnant channels.

With a lot if straight pathways cross drilled through the block, I know that laminar flow might pose a problem. I already have a few ideas on how to turbulate the flow inside each of the channels.

Using a Danner 500Gph magdrive pump with low flow restriction designed into every bit of the system- cooling CPU, GPU, & chipset (for now).

First, let me welcome you over here. We like OC, but we like a few more people over here too!

Your idea is similar to mine. I was thinking about a straight through design, but for CPU cooling, and with one wide channel only.

As for turbulence, you'll find that there's 2 ways to achieve it:
1) keep the design simple, and run a high flow rate.

or

2) use a lower flow, but induce the turbulence.

Here's a link

If you can run the math (which I'm about to do), then you'll know if the coolant flow rate you have is sufficient, or if you need to add some turbulence.

Ben I think that turbulence is somewhat a matter of degree in forced convection, and that even if the bulk fluid is in the fully turbulent regime there is still a boundary layer that can limit convective heat transfer. I would be concerned with this in a "single straight through" channel no matter the width. I think it is safe to assume that most of the cooling of the usual blocks happens right at the center inlet, where that boundary layer is given some serious mixing. Can't run numbers on that though, eh?

No numbers on that, but the center inlet makes a lot of sense if you look at cooling the block, the same way that it is heated: from the center out.

As for turbulence, I look at it in two ways: either you get it with a high flow, or by adding turbulators. Regardless of either of these, there is an optimization of the blocks' thermal transfer properties that can be achieved with fins.

Combining these two factors, I believe, is the key to the Ultimate Block.

Seeing that bigger pumps add more heat, it would make sense to minimize a) the flow restriction and/or b) the channel depth/size, in order to achieve 200 gph+, a good flow rate for the purpose (without going nuts with a large pump).

I'm thinking about either fins, or the perfect rows of square pyramids, but I'll have to run the numbers.

BigBen,

I don't want to put a damper on your quest, but when I see stuff like "200 gph+", I gotta comment. You've already been through the exercise of water's thermal properties. You know that flow rate * delta-T equals power. Taking the relevant units, watts = gph * °C / 0.227 or gph = watts * 0.227 / °C.

This means 100 watts causes a delta-T of 1°C at 22.7 gph. At your "200 gph+", say 227 gph, delta-T for 100 watts is only 0.1°C. This 0.9°C improvement for a 900% flow rate increase is pretty pathetic.

Granted, what matters isn't delta-T in the water but rather delta-T between the die and the water. This still isn't so much a function of volumetric flow rate, though, as it is velocity and surface area.

I realize I'm not telling you anything you don't already know, but it seems you may be straying a little. Just remember, it's all about balancing the entire system and the block is just one part. You could have "the world's best block" and still have a lousy system if the remaining components aren't right for that block.

bigben2k
been done, and quite well I would observe (having tested it)

http://thermal-management-testing.com/HootsWB.jpg

some details here
-> ask Hoot for the results

you should get out more,
whole bunches of 'the obvious' being talked to death here
google is your friend, or should become so

No problem, you know that I need to be put back on track, once in a while:D

Actually, I'm going with this calculation. This fellow (michael westen, Holland, he might have taken the graph from BillA) gave us some PRELIMINARY numbers, where 200 gph (effective) flow (w/ 5mm thickness) will achieve 3 deg C cooler than 100 gph (w/ 10mm baseplate thickness). I don't believe that going for 300 gph (2mm) is practical, because then the baseplate would be prone to bending under pressure, especially if I slap a pelt on it at 150 to 300 psi.

So here I am, at 200gph+:D , 5mm baseplate thickness, figuring out a good fin arrangement, and channel cross section pattern.

What do you think now?

Well, that's what I'm looking for, sort of...

As for the obvious, well, that's ok: I don't spend much time out of ProCooling, so I'm kinda counting on you to keep me in touch with the rest of the world:D !

(BTW did Hoot ever try his 1250 on it?)

But that's still not quite what I had in mind.

a) for a CPU cooler, I was thinking about a straight through, one channel design. No turns, no angles, no restriction whatsoever (well, maybe except for a couple of 45s in and out), except for a shallow channel and some fins. This channel would only be a bit less than twice as wide as the CPU core. Alternatively, it could have a center inlet, that splits out the sides.

b) for a pelt, the channel would have to be wider, but maybe that could be compensated by an even shallower channel.

This is mine....and I know that it looks like one that is made....

But here there is high flowrate, big surface and with the holes/bumps in the cobberplates turbulence sould also be there..... = Ultimate block ?

Build a straight through tube with copper wool inside that is firmly attached to all walls. Make it with 1" fittings and 3/4" interior diameter. That'll absorb some heat. The design you just suggested has huge areas that will contain stagnant hot water.

That's close!

I was thinking about fins that are no larger than the inlet/outlet though. The channel would be maybe 1/2 inch wide, and maybe 1/4 inch high.

Me....good ? :D

Naaa.....but this ide is quite old, and I have showed it before....it didnt falled into peoples tasts :(

I can se that some hot water will be "trapped". So I could just make it a little lower.

here.........

I don't think that the waves are necessary, but hey, it might improve things a little. It's more likely to create some deadspots though (indicated by the bubbles on your pic), or some less turbulent spots anyways.

I'd stick with the straight fins. I don't see the purpose of the holes, if the flow rate is high.

To build it, I'm thinking baseplate, CNC some shallow grooves, and braze the fins in place. Dunno about the top yet.

So this design of yours is for a pelt? I ask because the channel is so large, and that brings up the issue of using a manifold to get the water in and out, so that the flow is spread evenly. I'm not there yet...:D

Hey BigBen,

I finally took a look at that thread you referenced about varying base thickness versus flowrate. I'll tell ya this: The "best" baseplate thickness will depend on how the block is designed. If it relies on direct impingement over the die, then a thinner baseplate would be best. If it relies on transferring heat over an area much larger than the die, a thicker baseplate would do better.

This sort of thing recently popped its head up when I started looking at the new 0.13 micron XP chips. They have a die area of ~80 mm^2 versus the "old" XP die of ~128 mm^2. Even though total wattage is lower, heat flux is quite a bit higher with the new chips. This is one of the reasons why people aren't seeing drops in temperatures despite much lower power requirements.

The new XP chips will do better with heat sinks (air cooled) that have a little extra baseplate thickness. This is because the air cooled heat sinks rely on getting the heat spread out to the fins/pins that populate the entire surface of the baseplate's upper side.

Water blocks fall into two very broad camps. One's like Michael Westen's would rely on getting the heat spread out over a large surface area. This requires a thicker base than ones that use direct impingement. (On a side note, Michael's block with channels 1.2mm wide is going to challenge the strongest of pumps. You start getting into gaps of 1.2mm (roughly 0.042") and you dive into a whole 'nother realm of fluid mechanics. Fluid surface tension and adhesive properties begin to take on significance not seen in larger channels. I suspect he'll find this out soon enough if not already.)

These two broad camps work on different premises. Michael's block sacrifices surface velocity in exchange for copious surface area. Direct impingement blocks do precisely the opposite. I couldn't tell you which is better with a strong degree of confidence, but I lean toward the direct impingement approach personally.

regarding the finned design; After my work with the 1 inch block (see my "am I insane..." thread,which is on the back burner untill I can source some more flexable tubing) I want to test both the multiple wire and flat finned fan concepts that I've shown here before but in a more "sane" 1/2'' design.

That way I can test them more reastically against my current block and give constructive feedback from something that would actually be usable by most O/Cers rather than some monstrosity that isn't really practical.

I already have a base from a previous exprimental block that I can use so hopefully over the weekend I can knock something up and test it. I'll also do some testing with different flowrates on both my existing block and the new one.

If I were to make a "finned" waterblock, I would cut it out of a solid block of copper instead of brazing the fins to a plate. I'd use a band saw to cut the fins out.

Bandsaws are fun:D
Here's a few things I made with mine,

Holy copper heatsinks batman!

nice:D

Well........there seems to be so awful many things that implie when building a block. So many things that I find it quite impossible to make the ultimate block and if done...it would be more luck than knowledge.

So...why dont "just" go with this little beauty, that performs only one degree over Innovatek rev. 3.....

I will, cause all this is giving me a headeg :(

BUT it could be fun to make a block....but again, I think it would be more luck, than knowlegde if it would be a performer...

To expand on that a little... the single straight through design I was thinking of, would have those perfect rows of square pyramids, and I might even offset some of the rows, across the flow path, for good mesure (maybe a staggered pattern). The question remains though, how thick should the baseplate be, and how deep/wide does the (single) channel need to be?

I might even take it a step further and split an incoming flow from the top, in which case, it's a different flow dynamic, and different size channels. With tiny fins, along the exit path, but right over the core, it might be good...

Would this work ? I know that the flow isnt. THAT high but again....i "know" that if the flow dosnt. go under 60l/hr then everything will be fine.

It is the Alpha heatsink, that I have drawed apon.