My first waterblock ....

[Predator]

First, HI to all. My first post here. I admire you
I want to design / manufacture, for the start an WaterBlock.
I have read the entire forum, to understand how and wb works and it`s designed.

I want from my wb to have very good performance, while having a good aspect.

I picked several designs :

1. Jets + Holes ----- simmilar to Swiftech Storm ( Cathar you rock ! )

2. Fins

3. Od-balls ( a good guide : here )

4. Impingement ( can someone explain this to me ? ) " Impinge-ing a base is just the process of adding tons of pins for the water to fall on making turbulence and good conditions for the removal of heat from the block. " ---- what are the differences between this and pins/pillars design ?!

The top of the wb will be frosted acrylic (or simply acrylic) - with a metal plate for socket retention ( i think it will be multi-socket )

Tomorrow i will tell you the manufacturing process ( hope i will find a CNC ) if not suggest me a good option to create the wb.

My biggest request is to help me, choose a performant design, create the drawings of a very good and efficient wb.

Thank you

My rig:
Abit IC7
P4 2,8C @ 3,6 - 1,6 V
Scythe Ninja
Kingston 2x256 BH5
Chieftec BA-02B-B-B.


Sorry for my bad english ....

[Predator]

First attempt to draw one, with some help from a "watercooling expert "
Tomorrow i`ll post some of my own autocad creations, and remake this one.

----REMOVED------

My first wb design:
I wanted to focus all the water flow, on the mid section of the block, to remove heat faster...
The fins will be much closer, not like in the drawing...



Second design ( if there is an copyright, I`m sorry i will remove it imediatly )

Using jet impinged tech.

[Captain Slug]

I couldn't open your PDF for some reason so I'm not sure what you've come up with. But to answer your question:
Jet impingement is a very effective (but costly interms of restriction) way of significantly reducing the stagnant boundary layer (which adds thermal resistance) on a cooling surface.

Jet impingement as used now in waterblocks typically involves tubes inserted into cups, which is a fairly elegant solution. Other configurations have been suggested but none that are any easier than tubes + cups to implement.
flat-bottom and square edged cups so-far have produced better results than cups with pins.

All waterblocks are designed to do the same thing: To transfer the thermal energy as efficiently as possible from the copper to the water. In order to do this you need to

1. Minimize the boundary layer. When water is flowing through any channel the water closer to the edges of the channel will be travelling slower than the water in the center of the channel which is experiencing less resistance. This inhibits efficient thermal conductivity, and to combat it the channels need to have an adequate level of turbulence.

2. Minimizing thermal resistance. More is not always better, and there's a limit to the ability of thermal energy from the processor to conduct through the copper block. Therefore the base and effectively "working" area of the waterblock need to fall within a certain dimensional space on the block. This also means that there is a volumetric limitation to how much working surface area and material you can have as copper. You want a thin base, thin fins are pins, and certain size channels. Many optimums have been found so unless you plan to spend alot of time running your own thermal engineering equations you want to work with known ratios.

And if you do not have ready access and experience using CNC I don't recommend pursuing it for your first block (for both cost and practicality reasons). What tools DO you have access to?

[Predator]

I have made some "research".
To have the best possible heat transfer, i must have turbulent flow (not laminar).

"There are several factors that determine whether a flow will be turbulent or not: channel size and shape, velocity of the fluid, physical attributes of the fluid, etc."

"In order to maximize the heat transfer, turbulent flow must be induced as soon as possible into the flow - the entrance length must be minimized." --- Entrance length means what ?? The intake tube ?!


----Got it : "Entrance Length is defined as the length from the entrance of the water block to such a point that the flow is fully developed."

To create a turbulent flow i must :

1.Increase the flow velocity or ... (step 2)
2.Add turbulators at the flow entrance and/or along the entire flow length.

But if combine step 1 and 2 ? it will have more turbulences rather than using a single step (1/2) ?

"Channels with smooth walls and ridges that run parallel to the walls will tend to smooth out the flow and can take turbulent flow and turn it laminar. There has been much research done on mach level aircraft where very small ridges are run the width of a wing to prevent turbulent flow, just the opposite that water-cooling enthusiasts seek."

Ok, no paralel fins ....

"A fully developed flow is one in which the boundary layer is not changing as it moves further down the channel. When water first enters the water block, only the very closest molecules to the surface of the block feel the effects of friction. As the water moves further down the channel, more and more molecules begin to feel the friction effects.

All internal flows will have a certain entrance length and in this entrance length, the flow is laminar - exactly the opposite needed for good heat transfer. The entrance length varies with the velocity of the water entering the block, but can be up to 60 times the diameter of the channel. This could mean that the flow never becomes fully developed (thus would never be turbulent) before the water exits the water block."


----HELP! ------




Here the velocity entrance length is shown (hydrodynamic entrance region). Once the fluid has passed the entrance region, the velocity profile remains the same for the rest of the length of the channel.



The thermal entrance region is very similar to the velocity entrance region with a few exceptions. If heat is being input along the entire length of the channel, the basic shape of the temperature profile will not change, but the total average temperature will continue to increase. This can be seen by comparing the arrows representing the temperature in the middle region with those in the rightmost region.

Minimizing thermal resistance. More is not always better, and there's a limit to the ability of thermal energy from the processor to conduct through the copper block. Therefore the base and effectively "working" area of the waterblock need to fall within a certain dimensional space on the block. This also means that there is a volumetric limitation to how much working surface area and material you can have as copper. You want a thin base, thin fins are pins, and certain size channels. Many optimums have been found so unless you plan to spend alot of time running your own thermal engineering equations you want to work with known ratios.

Reducing thermal resistance.

Originally Posted by davidzo

No they're not about surface area. Its about bringing the heat from the die surface to the medium Water.
So you need to decrease the thermal resistance between die and copper, the copper itself and copper and water. Die and copper is easy, use some good thermal paste, that will do a good job. Reducing the thermal resistance of the block itself sounds easy too, just keep the material between die and water very thin. One problem with too thin baseplates is thet they bent, so don't overdo it. 2mm is good, 1.5mm is the barrier, there are some who try thinner baseplates with some webs to stabilize it.
The most complicated part and the part where you can get the most out of if you do it good is to increase the heat transfer between the copper surface of the block and the water. Increasing the velocity is an easy answer, but its difficut because of the boundary layer. Eeven if you double the velocity, the isolating boundary layer won't get much thinner. thats why you have to try to use turbulences to increase the velocity not only overall insiede the channels but especially directly on the copper surface.

Tip: decrease the restrictivity werever possible. Increase velocity and turbulences through slits, small channels and bends where the die of the cpu lies. I would mill some reservoirs to the left and the right to decrease the pressure drop there while keeping the channels in the middle as small and filligran as possible (many parallel slim channels). Now the area of the fine channels is rectangular and very longm much longer as the die and much too long for effective heat transfer. effective channels are only in the middle. make the channeled area a square and cut the rest into big less restrictive reservoirs.

Posted a second design here --- DESIGN 2

[Captain Slug]

What tools do you have access to?
And I don't quite understand your design since there's no label to say what it's representing. If it's a top-down view then I don't think it would be too effective nor would it be very easy to machine.

All internal flows will have a certain entrance length and in this entrance length, the flow is laminar - exactly the opposite needed for good heat transfer. The entrance length varies with the velocity of the water entering the block, but can be up to 60 times the diameter of the channel. This could mean that the flow never becomes fully developed (thus would never be turbulent) before the water exits the water block."

You are misinterpreting the meaning of the drawings. The first drawing is explaining the length of the transitional period between flow being compressed into a channel and the length of travel require for it to reach a state of laminar flow. The second image is a corresponding thermal resistance wave.

What those images tell you basically is that you do not want perfectly strait non-resistive channels that travel any considerable amount of length without bending. In turn they also hint that if you do have a block with long channels that you want the inlet to not feed the water into the channels anywhere other than at the center of the block.
You're confusing turbulence with velocity as represented in the image. The image does not directly expain turbulence at all, but rather a reduction of turbulence over time.
The water is very turbulent near the "mouth" of the channel but becomes less so as it travels further into the channel.
Those images only relate to jet impingement in-so-much as they hint at what the optimum cup depth should be for peak turbulence.

[Predator]

Originally Posted by Captain Slug

You are misinterpreting the meaning of the drawings. The first drawing is explaining the length of the transitional period between flow being compressed into a channel and the length of travel require for it to reach a state of laminar flow.

FALSE

All internal flows will have a certain entrance length and in this entrance length, the flow is laminar (exactly the opposite needed for good heat transfer)

Originally Posted by Captain Slug

You're confusing turbulence with velocity as represented in the image.

Where ? High velocity means high turbulence, no ?!

Originally Posted by Captain Slug

Those images only relate to jet impingement in-so-much as they hint at what the optimum cup depth should be for peak turbulence.

No, those image relate a wb intake.

[Talcite]

I disagree, high velocity does not mean high turbulence.

High velocity has a tendency for high turbulence, because there is a likelihood of increased turbulence from the edges of the water touching the material e.g. pipe.

However, if a high quality pipe or... a water stream in a vacuum was built. Then your velocity could be as high as you wanted and flow would be more or less laminar.

And in a waterblock setting... high turbulence can be achieved at lower velocities if using things like jet impingement techniques.

[Predator]

Originally Posted by Talcite

High velocity has a tendency for high turbulence, because there is a likelihood of increased turbulence from the edges of the water touching the material e.g. pipe.

And in a waterblock setting... high turbulence can be achieved at lower velocities if using things like jet impingement techniques.

True.

Laminar Flow

Laminar flow is the flow if a fluid in an organized manner in layers, or as the name suggests, laminates.

For our application, if the flow is laminar, water enters into the water block and flows through the block in nice even layers. Molecules of water stay in the same layer of water as they continue on their path. The molecules of water closest to the water block will be the hottest and moving the slowest, and those in the center of the flow will be the coolest and moving the fastest. This holds true for the entire path through the block and out the exit.



Turbulent Flow

Turbulent flow is just as the name suggests, very random and unorganized.

For one reason or another, the nice laminar layers of fluid somehow get mixed up and the molecules of the fluid no longer flow along nicely but rather bounce all over throughout the flow. Besides the very thinnest of layers right next to the block which remains the hottest and moves the slowest, there is not an even distribution of temperature or velocity through the majority of the flow. Everything is all mixed up and tumbling about itself.

Referencing the above image, the rightmost side shows the turbulent section. While there is an underlying thin laminar layer nearest the wall, the majority of the flow is random and unpredictable.

Boundary Layer

The boundary layer is defined as the area of the flow that has shear stress forces induced by the solid wall of the water block.

What this basically means is that the boundary layer is the part of the moving water that is feeling the friction or the 'drag' of the wall. The molecules of water that are closest to and touching the water block wall are not moving at all, but are stationary. As the distance from the wall increases, the molecules pick up speed until they are far enough away that the flow feels no effects from the wall; this is called the free stream velocity.

No matter the case, there will always be some kind of boundary layer.

The problem with having a boundary layer for heat transfer in a water block is that it is actually insulating the inner most layers of flow from being able to pick up the heat from the water block. This is especially true of laminar flow because the boundary layer is very thick and, in channels that are small enough, the boundary layer may extend through the entire flow.

However, in turbulent flow the random action of the water molecules breaks up the boundary layer and disperses the majority of it, thus increasing the ability of all the water molecules to pick up heat from the water block wall.

This image shows the boundary layer represented by d(x), or the thick black line. The velocity of the flow is shown by u. Before the flow gets to the wall, u is even and consistent. As the flow continues along the wall, the friction effects of the wall slow down the individual water molecules. Any molecules above the boundary layer remain at the initial entrance velocity, while the molecules next to the wall are stationary.

In this image, T represents the temperature of the fluid. Just as with the velocity, the temperature of the fluid is even and consistent until it reaches the wall. If the wall is hotter than the fluid, the fluid closest to the wall reaches near-wall temperatures, while the fluid above the boundary layer remains at the same temperature as the fluid entering the channel.

[phide]

What'll you'll find is that flow through your block will generally be classifiably turbulant no matter what you do. The Reynolds number is used to determine whether flow is laminar or turbulant, and you can do the calculations yourself quite easily. At the flowrates in a typical system, reducing the cross-sectional area of the interior plenum is enough to get the Reynolds number (somewhat) high. So, don't really concern yourself with turbulance.

The boundary layer is a very important concept when it comes to block design. In a pin grid block, for example, numerous turbulators (the pins themselves) increase turbulance by a great degree, and also reduce boundary layer formation. In the Storm, small pins in the cups are designed to "decimate" the boundary layer the moment before most heat transfer will take place, though it should be said that the jets themselves contribute a great deal to the block's overall performance. Without carefully planned jets, the Cascade/Storm wouldn't perform nearly as well as they do. No matter what design you choose to go with, you want there to be adequate implements designed to keep the boundary layer as "thin" as possible.

Most of all, you don't want to try and push the limits so hard that you end up severely limiting the overall flowrate of the system. You should first try and decide how well your particular system can handle a restrictive component and build from there.

[davidzo]

I fully agree with what you wrote about the boundary layer, it is what i pronounxe the whole time, turbulence is needed.

But I disagree with this sequence:

All internal flows will have a certain entrance length and in this entrance length, the flow is laminar - exactly the opposite needed for good heat transfer. The entrance length varies with the velocity of the water entering the block, but can be up to 60 times the diameter of the channel. This could mean that the flow never becomes fully developed (thus would never be turbulent) before the water exits the water block."

Captain Slug is right in most of what he wrotes. The heat transfer is the best in the entrance region of a channel, because there the boundarylayer is the smallest.

First of all, the diagramm is corresponding to a laminar flow scenario, so don't try to make conclusions to turbulent flow, that would look far different and is more complicated and very depending on velocity.
Full developed flow is in this case (a laminar) flow with a constant velocitycurve of a paraolic shape throughout the length of the channel.
The dottet region represents the boundary layer where velocity decreases linear the nearer to the channel wall. That means that full developed Flow has a maximized boundary layer, so nothing to do with turbulence. and that is what we try to prevent. The lenght of the arrows represent the velocity in the channel. The short arrows are water molecules with a very low velocity which are isolating the copper wall from the fast flowing molecules (the ones with the long arrow). so if we take Einstein for real and change the framework from copperwall-watermolecule to low velocity water molecule and highe velocity water molecule, the there is a boundary layer between the low velocity water molecules and the high velocity water molecules which hinders the heat transfer. From that we learn, that the boundary layer consists of not only the water molecules that don't move at all, but also from the molecules that have a very low velocity.
Heat Transfer gets worse the longer the channel is.

i did this design because of that:

[Predator]

I saw that design, at "EK Wave (AMD64/P4 S478) Waterblock"
Thanks davidzo, for clearing up the situation for me .

Ok, now whats the best design ?
If i combine storm like wb with some pins at the exhaust region ?
Help me decide on a wb model with very good performance.

[diff_lock2]

Originally Posted by Predator

I saw that design, at "EK Wave (AMD64/P4 S478) Waterblock"
Thanks davidzo, for clearing up the situation for me .

Ok, now whats the best design ?
If i combine storm like wb with some pins at the exhaust region ?
Help me decide on a wb model with very good performance.

LOL same here im looking for a a good wb... im watching/waiting...

[Predator]

Let`s work as a team, making research and finding a good desing.
Standing and waiting for a good wb wont give any results.

[diff_lock2]

Good good lol, yup your right waiting and watching is not nuff but realy thats not what im doing, im looking at other wb's and thinking of way to make them at home... i look at ones with good performance.
and yes once we find a good design we can both make a wb with diffrent atributes and see how well it goes....

[Talcite]

I can't remember who it said it, but there is no "best waterblock". Different water blocks will perform better at different flow rates. The storm G7, which is considered one of the best blocks out there, works well because it cools efficiently across all pressures. By no means is it the "best waterblock". I believe the design phide gave me is probably one of the better ones. It uses jet impingment onto pins. It's incredibly restrictive however, so that's what you need to take into consideration. DIY waterblocks should be designed according to your personal needs. If you're going to design a block with jet impingement onto pins, then prepare to stick 2 or 3 pumps into the loop. You also will need to have something that generates enough heat to require that kind of cooling. Like a huge TEC or something.

Find out what you plan on doing, then design your block accordingly.

[diff_lock2]

Originally Posted by Talcite

I can't remember who it said it, but there is no "best waterblock". Different water blocks will perform better at different flow rates. The storm G7, which is considered one of the best blocks out there, works well because it cools efficiently across all pressures. By no means is it the "best waterblock". I believe the design phide gave me is probably one of the better ones. It uses jet impingment onto pins. It's incredibly restrictive however, so that's what you need to take into consideration. DIY waterblocks should be designed according to your personal needs. If you're going to design a block with jet impingement onto pins, then prepare to stick 2 or 3 pumps into the loop. You also will need to have something that generates enough heat to require that kind of cooling. Like a huge TEC or something.

Find out what you plan on doing, then design your block accordingly.

yup, i was told the same thing... sounds right... you got a huge tec?

[jaydee]

The designs are already there. No need to reinvent the wheel.

http://www.swiftnets.com/products/Storm.asp

http://www.swiftnets.com/products/APOGEE.asp

http://www.cooltechnica.com/Merchant...tegory_Code=WB

[diff_lock2]

lol ive seen all those... and the storm just looks so easy to make (other than the jets) and the apogegy (sp) just imosible.... along side that aquax (those tiny cuts with that electric wire thing lol....) in that case why not go with the storm, but the this is im going to be trying to run a eheim 1048 witch aprently will not go so well with jets...

[Predator]

Ok, guys time to help me out.
A local company, has accepted my waterblock project.
They requested me a drawing in corel.
The pump will be chosen for the waterblock type.
I have chosen a similar design to G7, any suggestions ?
Help me do the drawing in Corel, cause I`m tottaly noob.

[davidzo]

they will chase you out of the shop when you come up with something G7like. if you only do one block that will cost them more than a day and a lot of expensive drills to make one prototype of thsi complicated block.
Better start with something whitewaterlike or a pincooler with middle inlet, jetholes and not too many pins. That will be much easier for them to make. be aware of drills smaller then 2mm, everything smaller is not efficient to use and only for special parts where cost and afford does't matter that much.

[jaydee]

Wonder what kind of equipment they have that uses Corel? What format (2d, 3d, file format?) and what version of Corel? Doubt anyone is going to draw you block in corel though.

[Predator]

Ok, my first drawing in corel.
It only represents top view.
no descriptions

[Talcite]

the machinists don't actually use corel xD. They just redraw it in cad. Cathar had similar experiences. He drew in paint and the machinists transcribed into CAD.

The thing is that machinists now have to learn how to use CAD more than they have to know about actual cutting and stuff. So much for trades jobs being easy =p

[jaydee]

Originally Posted by Talcite

the machinists don't actually use corel xD. They just redraw it in cad. Cathar had similar experiences. He drew in paint and the machinists transcribed into CAD.

The thing is that machinists now have to learn how to use CAD more than they have to know about actual cutting and stuff. So much for trades jobs being easy =p

We used to use Corel Draw 9 on the Laser and Rotary engraver. Corel can output .dfx's and other useful formats. If they are just using that drawing as a reference then they are going ot charge you an arm and a leg just for redrawing it into CAD/CAM.

Not sure why anyone would spend this kind of cash just try and replicate a $85.00 block.

[Predator]

A 80% complete drawing.