My Alphacool Acrylic DDC Mod Top

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07-25-2006, 09:21 AM
Sneaky

http://www.fragtek.com/sneaky/illuminati/ill_29.jpg
http://www.fragtek.com/sneaky/illuminati/ill_30.jpg

looks like the inlet on the impeller is just under 1/2"... but I noticed that on both the alphacool and the stock DDC top, theres a little lip on the inlet on the top, that looks liek it helps direct water into the impeller, and that gets drilled away when you enlarge the hole to 1/2"

edit: also, on the box, it says 11w pumps, and I can't find any label on the pump that say that they're the 18w versions... but considering it has an orange/red impeller, that means that its an 18w pump, correct? (IIRC 18w = orange/red impeller, 11w = black impeller)
07-25-2006, 09:31 AM
creidiki

Indeed, I suspect most of the loss of pressure comes from the elimination of the lip.

The ideal solution would be to have enlarged inlet w. lip, but thats not really doable.

I'd love to see some detailed pics of the radiical top...
07-25-2006, 09:39 AM
andersson.j

The first DDCs were 10w with black impellers. Then came the 18w red impeller version with better performance. Now your 11w with red impeller. Maybe it's a more efficient 18w? I wonder how they rank performance wise?
07-25-2006, 10:40 AM
eXa

i dont understand why you drilled so much. its no point in having the hole in the plexi larger than the inner diameter of the barb. so i would use a barb and find a drill bit wich fits exactly inside the barb and drill through the barb!
07-25-2006, 10:54 AM
Sneaky

Quote:

Originally Posted by andersson.j

The first DDCs were 10w with black impellers. Then came the 18w red impeller version with better performance. Now your 11w with red impeller. Maybe it's a more efficient 18w? I wonder how they rank performance wise?

well i got it from danger den, and the part number matches that of the 18w (DDC-2TPMP)... so i HOPE that its an 18w pump...
07-25-2006, 10:56 AM
Sneaky

and also... here's pics of the radiical top from a guy over at OCF:

http://www.ocforums.com/attachment.p...chmentid=51496
http://www.ocforums.com/attachment.p...chmentid=51502

edit: and more pics from a guy here at XS:

http://i20.photobucket.com/albums/b2...a/IMG_1374.jpg

Package contents
http://i20.photobucket.com/albums/b2...a/IMG_1375.jpg

Bottom
http://i20.photobucket.com/albums/b2...a/IMG_1378.jpg

Top Intlet
http://i20.photobucket.com/albums/b2...a/IMG_1379.jpg

Side Outlet
http://i20.photobucket.com/albums/b2...a/IMG_1381.jpg

The logo
http://i20.photobucket.com/albums/b2...a/IMG_1380.jpg
07-25-2006, 11:12 AM
creidiki

Hmmm, big outlet, doesent bode well for head.
07-25-2006, 11:14 AM
JoeBar

But smoother flow...?
07-25-2006, 11:17 AM
creidiki

Smoother? Its pretty clear by now that making the inlet/outlet larger on the DDCs induces a head/flow tradeoff.

Whats the optimal ratio? Thats the question. We shall know more than that H20Koeling(sp?) site finshes their DDC+ review. Then we'll have good PQ curves for the standard AC top, and be able to derive rough guidelines for what top/mod is best for what system.

Until then its a bit roll of the dice, tbh.
07-25-2006, 11:24 AM
Radical_53

Totally agree. Bigger inlet makes sense somehow, lip makes sense, big outlet does make sense (same ID as barbs), yet big outlet also means less pressure (normally).
So, let's see what they find out.
07-25-2006, 11:25 AM
JoeBar

Indeed, it will be a guideline. Let's wait and see...
07-25-2006, 01:31 PM
MaGiX

Did some testing the other day, the results was stranger than I had ever imagined.

First off, I only tried with a 10W edition, but later this week, I do hope to get around to doint the same test with af 18W version, but that part is not yet sure. The whole thing should end out in an article on our site (sorry guys, it’s in Danish, but we are working on translating it to English also.)

I started with drilling/filing the top hole up from 7 mm to 9 mm. Got an increase in both flow (0,5 L/m) from 9,5 L/m to 10,0 L/m, and an increase in the pressure (+8 mbar.) going from 318 mbar to 326 mbar.

Not much, but some increase after all.

Then I bored the top up to 11 mm, and got pretty much the same result as with 9 mm (and yes, the ID of the fitting followed up, using 16 mm fittings.) That made me conclude, that drilling up to much more than 10 mm is useless, there is NO gain to se after that.

Then I started drilling the front open to the exit, hoping to gain additionally flow, and pretty much got an opening like the Radiical top. This mod I can NOT recommend to any one, there is a lot of small drill holes pretty darn close to the outlet, and avoiding those cost me all in all 2 tries (the first became leaking, through the mounting holes.)

The test results was to say the least very disappointing. I lost the entire flow and pressure gain at once, going from 10,0 L/m to 9,0 L/m, but the worst was the pressure drop, of almost 100 mbar, going from 326 to 233 mbar…

I do not know, if Radiical have made some smart build in there tops, that makes both the flow and the pressure going higher than my results, I have tried to get a test example from them, but not heard a darn thing from them in almost 3 weeks now, so don’t thing the message got through :P

Perhaps I should at this point link to an image of the test rig used for these test results:

http://h2okoeling.dk/images/articles...p/DSCF2424.JPG

As I said, the whole thing will get out in a article in a couple of weeks (I hope) and in that article there will be a lot of P/Q diagrams of this failed test, but it was fun to test :)

Still and once again, if anybody got af Radiical top lying around, and happens to be near Denmark, I will love to test that top, and do a comparison of all the other blocks on the market…

MaGiX
07-25-2006, 01:36 PM
nikhsub1

Quote:

Originally Posted by MaGiX

Then I started drilling the front open to the exit, hoping to gain additionally flow, and pretty much got an opening like the Radiical top. This mod I can NOT recommend to any one, there is a lot of small drill holes pretty darn close to the outlet, and avoiding those cost me all in all 2 tries (the first became leaking, through the mounting holes.)

The test results was to say the least very disappointing. I lost the entire flow and pressure gain at once, going from 10,0 L/m to 9,0 L/m, but the worst was the pressure drop, of almost 100 mbar, going from 326 to 233 mbar…

Not surprising really, just as I suspected... there is a REASON Iwaki's output barb opening is unusually narrow... it creates pressure. Imagine a garden hose. Take it and turn it on with no nozzle, maybe it goes straight up 3 feet or so. Now put a good nozzle on it and do the same, it will shoot up 50 feet. Try the same through 10 feet of tubing... you get the idea.
07-25-2006, 01:39 PM
creidiki

Any chance you could try drilling the top open to 11-12 to see if there's a point where you start losing head, like some people have reported?

I suspect once the ID of the inlet become larger than the ID of the impeller's hole you start losing pressure from crossflow around the front of the impeller.

In any case, I hope you manage to test the 18W :)
07-25-2006, 05:22 PM
Sneaky

Quote:

Originally Posted by nikhsub1

Not surprising really, just as I suspected... there is a REASON Iwaki's output barb opening is unusually narrow... it creates pressure. Imagine a garden hose. Take it and turn it on with no nozzle, maybe it goes straight up 3 feet or so. Now put a good nozzle on it and do the same, it will shoot up 50 feet. Try the same through 10 feet of tubing... you get the idea.

nikhsub1, you drilled out your DDC tops though, correct?
07-25-2006, 05:38 PM
sdkevin

what is your purpose of enlarger inlet? enlarger inlets will result in slight loss head and improve flow rate, if you don't want extra flowrate then keep it the way it was
07-25-2006, 05:41 PM
nikhsub1

Quote:

Originally Posted by Sneaky

nikhsub1, you drilled out your DDC tops though, correct?

Yes...
07-25-2006, 05:42 PM
nikhsub1

Quote:

Originally Posted by sdkevin

what is your purpose of enlarger inlet? enlarger inlets will result in slight loss head and improve flow rate, if you don't want extra flowrate then keep it the way it was

Err, I'm running mine in SERIES so IDC about a slight headloss per each pump but the improved flowrate is nice.
07-25-2006, 05:48 PM
sdkevin

Extra flowrate is needed for those with UFO Cases since you have your pump on other side which results in longer tubing to route than Standard Cases
07-25-2006, 05:55 PM
SiGfever

It seems to me that if you keep the inlet size just under the impeller opening the water will be directed into the impeller with the smoothest flow and keep the impeller feed rate correct.

And beveling the opening so that it is larger on the outside than on the inside at the impeller opening will also help with a smoother feed to the impeller. JMO
07-25-2006, 06:15 PM
creidiki

Quote:

Originally Posted by sdkevin

Extra flowrate is needed for those with UFO Cases since you have your pump on other side which results in longer tubing to route than Standard Cases

Actually extra tubing = bigger pressure drop = more need for head, but nvm... :rolleyes:
07-25-2006, 06:54 PM
eXa

is it possible to do something to the small holes at the impeller itselves?
07-26-2006, 01:32 AM
Radical_53

The fact that the bigger outlet is a problem does indeed make sense. But then, how do you make them run in series "perfectly"?
Accept the loss of some performance of the first pump, giving her a big outlet to use a big inlet on pump two, or scale in and out so that each pump has a bigger inlet than outlet? Then you'd end up with a tiny bore on the outlet of pump two...
Also interesting to see this as some users reported the Radiical top to be performing better, which wouldn't make sense after this test as it has both big in- and outlets.
07-26-2006, 03:08 AM
nealh

Quote:

Originally Posted by Radical_53

Also interesting to see this as some users reported the Radiical top to be performing better, which wouldn't make sense after this test as it has both big in- and outlets.

Can you point me to there threads I am interested to see the results since I bought the Radiical top..really is very nice and small but I wish I knew they were enlarging the outlet slight from rev1...probably would have gone with the alphatop
07-26-2006, 03:11 AM
septim

combine 2 outputs to 1? use a Y fitting

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