Actually I have got no tubes at all, only the drill holes in the 2nd copper block. The distance between the holes and the cups is 2mm or less, as far as I can remember.
This is one difference to cathar's cascade, where the tubes end in the cups afaik.

my cups have got the same diameter as the holes (49! with 1.2mm diameter).

Well I'm going to test this stuff as soon as I have got the other komponents for my watercooling systems and the final blocks.

Maybe Somebody will test the blocks too.

Looks (in design principle) like one of my early prototypes:

http://www.employees.org/~slf/mci/mci4.jpg

The distances between the holes and the cups was about 2mm.

I had 72 holes in that prototype. It performs okay. Not quite up there with the White Water.

I almost dropped further development on the Cascade design after seeing the results with this block, but decided to persist.

After researching a lot on submerged water jets and looking at a fair bit of experimental data I would recommend that you try to set Z/d=5. Where Z is the jet height and d is the jet diameter. It might be a good starting point as this tends to give the best heat transfer coefficient between the copper and water for a wide range of water velocities
Will

Anywhere between 4 and 5, but yeah, 5 is a good starting point.

Do you have a url with an example of this work or is access to a university library recquired.?
Have,for some time, been enquiring about the papers which show this ( http://forums.procooling.com/vbb/sho...5&pagenumber=3 ).

I found lots of information in the "Advances in Heat Transfer" journels from my uni library

Ah, the privileged
Long gone are those days
Now have to survive on common fare - the odd grain of wheat amidst endless Google chaff

If I remember correctly, my Z/d is about 3,3333... (I can't tell exactly because my plans are on the other computer)

but I'm looking forward to testing my block.

As soon as I've got the final versions in my hands, I'll take some pics again and post them here.