[davidzo]

Originally Posted by bobo5195

Turbulence and boundary layers dont work like that what so ever and in fact the entire sentence makes no sense.

No, do a little research on the reynolds formula and you will realize that besides the velocity, the channel diameter is the most important factor of Turbulence. When two channels have water with the same middle velocity flowing through them, the channel with the smaller width will have the more turbulence.

Shouldn't turbulance at/near the baseplate be essentially the same regardless of pin height?

No, see above.

Trying to alleviate restriction mostly by tweaking the jets. Since ~60% of the pressure drop in a G5/G7 is due to the jets, I'm mostly focusing on tweaking this particular area.

That is right. The Goal is to lower the boundary layer through turbulence at the heating surface and not inside the jets. In a tiny Pin jet Block, the jets are only for water distribution, not for velocity as in the Storm. A different approach...

TURBULENCE IS NOT A PRIMARY GOAL OF WATER BLOCK DESIGN. HAVING LOADS OF TURBULENCE MEANS DIDDLY SQUAT.

The main thing loads of turbulence means to me is that you are having loads of unnecessary pressure drop. It can decrease block performance by creating recirculation zones.

The primary goal of water block Design besides the old verities of blockdesign surface and distribution is to enhance the contact between the heatplate (copper/silver) and the transport medium (water). The only way to do this whithout boosting the surface is to lower the boundary layer with flowspeed. But as laminar flow goes, even extreme high flowspeed of the pump will have nearly any effect on the boundary layer. That is why you need turbulences to do the job. See here a very good Illustration from cooling-masters:


Avoiding recirculation is not so important as the heat-capacity of water is enormous, but keeping an eye on it while deisgning the flow through the block sure would pay off a little.

Secondly boundary layer has no concept in this kind of block. It is just a science word in this case.

Oh really? I think the whole block is based on that concept. Maze-style blocks may not be constructed around the laws of the boundary layer, but pin style blocks like The NexxosXP or this one here sure are.

~60% of the pressure loss comes from the jets but 100% of the performance comes from them.

I don't think so. This is not a blind hole style block like the G4 or G5. Why should only the jets bring performance, they are not even connected to the baseplate?!
In The Storm waterblocks the Jets create the needed Turbulence for the Cups, that is why they are so long. In a pin grid Block the channels should be so narrow that turbulence will result anyways, the jets are only for that the water from the laminar flow in the tubing gets spread over the surface of the pins.
In a Nexxos XP the biggest pressure drop comes from the pinGrid array. But there is still more pressure drop than needed at the inlet and with the outlet channels. But the narrow channels in the middle are close to perfect.