EK-DDC Dual TOP V.2, and a whole lotta n00bishnesses

[warriorpoet]

This is going to be an uber-n00by post, so beware.

OK. I know that this: http://www.petrastechshop.com/ladd1mcin12p.html

is a high-pressure, average flow pump.

I also know that this: http://www.petrastechshop.com/swmcin12pu.html

is the inverse.

But I understand this: http://www.petrastechshop.com/xstopforladd.html

increases the flow of #1, allows for larger/ different fittings, but reduces head pressure a small bit.

I also know that 2 #1s in series produces greater head pressure, and, presumably, so do two top-modified in series.


However...

I have been led to believe two #1s in series with only one inlet (like the EK dual turbo top) may increase flow, but does not increase head pressure in the same proportion.

Here's my n00bish question:

why?

...and do the modifications made to the EK-DDC Dual TOP V.2 improve this equation? The reservoir top modification seems to have paid large dividends in the XSPC top (and though less relevant, the Typhoon 3), but does it improve upon the concept of the v.1?

Inquiring minds want to know.

[Hondacity]

who said the ddc was low flow?

[warriorpoet]

who said the ddc was low flow?
meh. Not what I meant, but what I wrote :p

It's not a high-flow pump like the D5. It's more of an average flow high pressure pump. I'll fix it.

[faster3200]

I have been led to believe two #1s in series with only one inlet (like the EK dual turbo top) may increase flow, but does not increase head pressure in the same proportion.

Here's my n00bish question:

why?

...and do the modifications made to the EK-DDC Dual TOP V.2 improve this equation? The reservoir top modification seems to have paid large dividends in the XSPC top (and though less relevant, the Typhoon 3), but does it improve upon the concept of the v.1?

Inquiring minds want to know.

Having one pump feeding another pump will increase pressure. Having the two pumps join in a Y will increase flow.


who said the ddc was low flow?

Yeah, lots of people seem to think this. Based on Martin's calculations a DDC with top is actually higher flow and pressure than a D5. The stock DDC is lower flow though.

[Serpentarius]

Yeah, lots of people seem to think this. Based on Martin's calculations a DDC with top is actually higher flow and pressure than a D5. The stock DDC is lower flow though.

i'm kinda confused on this as well ... D5 claimed to deliver 1200 litre/hour
while DDC delivers up to 522 litre/hour (this is the largest volume i seen on DDC)

while flow is the volume of mass moved, how could DDC delivers more than D5?
maybe i missed out some discussion threads. Am i missing something?

[Boogerlad]

ddc delivers more because those values above are at 0 pressure/restriction.
Once you factor in restriction from your blocks, ddc wins.

[Edward88]

But ddc are too loud (355) . . . even that a dual d5. Thats not good

[Conumdrum]

I never see where they say a DDC 3.2 is too loud. I got two with XSPC restops, two 120x3 quiet rads and fans. I never ever hear my pumps.

They are mounted on teeny strips of velcro on top of a piece of wood about 1/4" thick.

Noise? Hmmm

[faster3200]

i'm kinda confused on this as well ... D5 claimed to deliver 1200 litre/hour
while DDC delivers up to 522 litre/hour (this is the largest volume i seen on DDC)

while flow is the volume of mass moved, how could DDC delivers more than D5?
maybe i missed out some discussion threads. Am i missing something?



ddc delivers more because those values above are at 0 pressure/restriction.
Once you factor in restriction from your blocks, ddc wins.

^^This and those numbers are with the stock top. With an after market top the inlet is relocated which helps the flow as well. I am sure the different volute helps, but with a spiral volute the pressure is increased as well.

[warriorpoet]

OK, I understand all this, guys, but what I really want to know is what makes the EK rev. 2 "better". Is it the inlet position, the res attachment, internal goodies or something else...

...or maybe not "better", just new and more flexible? Why would 2 separate pumps in series with an attachment be more efficient than two pumps in series sharing a top?

[skinnee]

single D5 w/ top vs. single DDC w/ top... and yes, this is the only teaser I'm releasing for now. :D

As for the individual vs combined... its close, all depends on if you have the room to fit it. I rather like the dual tops vs the individuals... yes my personal choice/opinion is swayed by aesthetics. :p:

http://skinneelabs.com/sample/D5vDDC.jpg

[warriorpoet]

I never see where they say a DDC 3.2 is too loud. I got two with XSPC restops, two 120x3 quiet rads and fans. I never ever hear my pumps.

They are mounted on teeny strips of velcro on top of a piece of wood about 1/4" thick.

Noise? Hmmm

DDCs are higher vibration, but once softmounted are equal in terms of free air noise (in my experience).

DDC 3.1s are MUCH less vibration prone than 3.2s, but, again softmounting solves the vast majority of the issue.

[warriorpoet]

single D5 w/ top vs. single DDC w/ top... and yes, this is the only teaser I'm releasing for now. :D

As for the individual vs combined... its close, all depends on if you have the room to fit it. I rather like the dual tops vs the individuals... yes my personal choice/opinion is swayed by aesthetics. :p:

http://skinneelabs.com/sample/D5vDDC.jpgInteresting, but still doesn't address my question on dual pump setups. I'd really like to know why conventional wisdom says 2 pumps sharing a top are only useful for certain specific apps. I think it was naekuh and Martin that came up with the two inlet for 2x DDC theory, but I can't recall right off.

Interesting to see the DDC and D5 come together like that at the end.

[warriorpoet]

skinnee, you are the pie-eating champ of ninja edits :D

[warriorpoet]

Wait a sec. That chart shows the T3 getting OWNED by a whole buncha pumps. What's up with that?

[skinnee]

T3 single loop performance is meh... I wrote that in the review. The T3 is a bay res pump top for the D5, and can run parallel loops which I found very interesting and rather exciting. However, the T3 review took on a life of its own and I think I was even accused of making money off of it... if someone has those mystery checks, I could use the cash right about now. :p:

Did my ninja edit answer your question?

Ninja Edit: nope it didn't... the multi inlets equate to less restriction at the inlet and will yield higher TDHP. However, its a balance... you can't open it up like a wide mouth bass and expect the TDHP to reach the sky. Thats what those hydraulic engineers sat in school for, I just know the workshop engineering of it. :)

[Hondacity]

ah the pump chart ... :D looks cleaner now :D

can you put curves....where the flow intersects with say different setups...like using a restrictive loop say..ek supreme...gtz...xt or heatkiller maybe :)

[warriorpoet]

T3 single loop performance is meh... I wrote that in the review. The T3 is a bay res pump top for the D5, and can run parallel loops which I found very interesting and rather exciting. However, the T3 review took on a life of its own and I think I was even accused of making money off of it... if someone has those mystery checks, I could use the cash right about now. :p:

Did my ninja edit answer your question?

Ninja Edit: nope it didn't... the multi inlets equate to less restriction at the inlet and will yield higher TDHP. However, its a balance... you can't open it up like a wide mouth bass and expect the TDHP to reach the sky. Thats what those hydraulic engineers sat in school for, I just know the workshop engineering of it. :)Hehe

You are cracking me up :)

I have read, re-read and re-re-read that T3 review and I still can't make any sense of what it means practically. I mean, it looks like a killer product for a very, very specific purpose, but what that actually means in a real-life loop in terms of C is a little...:confused:

What I DO know is DDC x2 + series= MASSIVE head pressure. Again, how that translates into real-life C is still a little...:confused:

...and why that series in the form of two pumps rather than a single top is still a mystery. I mean, don't two pumps in series essentially have a single inlet too?

What I want to understand is WHY two inlets on a dual DDC top are more desirable than, say, an expansion chamber (i.e. res), and how such a configuration affects a (1) standard CPU loop (Heatkiller, Apogee XT and Koolance MP350), (2) standard CPU + GPU loop (the above blocks + EK FC), and (3) a full-on loaded loop (all of the above + FC Mb block, maybe another GPU).

[skinnee]

Actually, thats exactly what Vapor's CPU block testing (http://vapor.skinneelabs.com/i7/Round2/Overall/R2i7Overall.html) is doing... what does pumping power mean to CPU block performance. Take a look at the Pumping Power charts...

Son of a ***** edit:

The reason for two individual tops achieving higher TDHP is because your barb and tubing provide less restriction than a triple elbow or a 6mm diameter connector betweeb the pump heads... but again, its a balance on that connector. Too big and you won't see any gains and probably some loss, too small and that second pump will act like an asmatic after running from an angry wife.

[warriorpoet]

Actually, thats exactly what Vapor's CPU block testing (http://vapor.skinneelabs.com/i7/Round2/Overall/R2i7Overall.html) is doing... what does pumping power mean to CPU block performance. Take a look at the Pumping Power charts...

Son of a ***** edit:

The reason for two individual tops achieving higher TDHP is because your barb and tubing provide less restriction than a triple elbow or a 6mm diameter connector betweeb the pump heads... but again, its a balance on that connector. Too big and you won't see any gains and probably some loss, too small and that second pump will act like an asmatic after running from an angry wife.'k, so a double top is adding restriction. That I get..

How 'bout the addition of the res to the dual top's inlet. Does that alleviate any of the inlet issues experienced with initial dual DDC runs, or is this something different?

[Hondacity]

two inlets? don't make a difference...

the impeller has one inlet...if you have a 355/350....look at the iimpeller....it has one hole..where the water is accelerated...

interesting is the xspc reservoir top...the inlet of the reservoir goes directly into the inlet side of the pump....explaining the higher flow...

[warriorpoet]

two inlets? don't make a difference...

the impeller has one inlet...if you have a 355/350....look at the iimpeller....it has one hole..where the water is accelerated...

interesting is the xspc reservoir top...the inlet of the reservoir goes directly into the inlet side of the pump....explaining the higher flow...
Dang it, where is that thread :mad:

Naekuh posted something about dual DDC tops only really being unleashed when the pumps were fed by dual inlets from a res. Before that they were wasteful. How the hey that ever made any sense, I'm not sure; I just want to try and understand, man.

[skinnee]

'k, so a double top is adding restriction. That I get..

Kind of... all depends on the flow path between the two pumps.


How 'bout the addition of the res to the dual top's inlet. Does that alleviate any of the inlet issues experienced with initial dual DDC runs, or is this something different?

Look at the inlet path... 1/4 BSPP inlet. Your gains will more than likely be elsewhere in the design.

Edit... yes, multi inlets can make a difference.

[Waterlogged]

Dang it, where is that thread :mad:

Naekuh posted something about dual DDC tops only really being unleashed when the pumps were fed by dual inlets from a res. Before that they were wasteful. How the hey that ever made any sense, I'm not sure; I just want to try and understand, man.

With a single inlet on a dual top, there is an increased possibility of the first pump becoming starved for flow, a second inlet prevents this from happening.

[warriorpoet]

Kind of... all depends on the flow path between the two pumps.



Look at the inlet path... 1/4 BSPP inlet. Your gains will more than likely be elsewhere in the design.

Edit... yes, multi inlets can make a difference.
True, but isn't the XSPC restop essentially the same (but uglier)- and there's some gain there over the standard top, no?

[skinnee]

break out the :hammer: on my explanation if needed WL.

Its not exactly the same, diameters are a bit different between the res and standard.

[warriorpoet]

Kind of... all depends on the flow path between the two pumps.



Look at the inlet path... 1/4 BSPP inlet. Your gains will more than likely be elsewhere in the design.

Edit... yes, multi inlets can make a difference.


With a single inlet on a dual top, there is an increased possibility of the first pump becoming starved for flow, a second inlet prevents this from happening.
maths. I needs them. :D

How does a dual top differ essentially from two single pumps in series other than possible added restriction between pumps?

[skinnee]

You're not getting the charts out of me tonight, good try though. :D

[warriorpoet]

You're not getting the charts out of me tonight, good try though. :D
Charts?

I thought you were just doing up single tops, no? *shifty eyes*

Anywho, I'd rather try and understand why something is than see a pretty chart (and it is very pretty :p: )and see that in one specific instance it is. General principles prove more broadly useful, in my experience :)

[skinnee]

I've already said too much then. ;)

And yes, you're correct... the principle is better. But I don't have the math on restriction for the Dual Top's connector between the pumps vs the tubing bridge of two individual tops, I can't get calipers in there or know the formulas to work it out, sorry. Or have I ventured so far from the original question that I am off by myself?

[Waterlogged]

maths. I needs them. :D

How does a dual top differ essentially from two single pumps in series other than possible added restriction between pumps?

Well, with most of the dual tops (either side by side or upside down) there is a short inflexible path from the first pump to the second and then a 90° into the impeller.

With two separate pumps and tops, the variable list can get a bit. . .um. . .complicated. You've got tubing length and size, fitting types (elbows or straight) and styles (barb, compression or push-in) as well as sizes all making their own little impacts on overall pressure.

Not sure if that helps you any. :shrug:

[warriorpoet]

No. At the risk of being labelled a "brick wall".

If the general principle of a dual top (inlet->pump1->bridge->pump2->outlet) is the same as a 2 pump serial setup (inlet->pump1->bridge->pump2->outlet), why does the dual top need more inlet area than the serial setup? In other words, why would pump1 in a dual top setup be any more starved for inlet than pump1 in a serial pump arrangement?

[Waterlogged]

AH, Got ya now!

Dual inlet feed will always help a dual pump setup, it's just most manu's don't consider the "dual pump philosophy" when designing a single top.

[Antioch]

No. At the risk of being labelled a "brick wall".

If the general principle of a dual top (inlet->pump1->bridge->pump2->outlet) is the same as a 2 pump serial setup (inlet->pump1->bridge->pump2->outlet), why does the dual top need more inlet area than the serial setup? In other words, why would pump1 in a dual top setup be any more starved for inlet than pump1 in a serial pump arrangement?

This answer I'd like to see :)

Although.. mayhaps it has to do with the fact that the bridge has a smaller diameter than the tubing used between your serial pumps? However, in a closed system I think all fluids move at the same velocity with equal pressure throughout (hence hydraulic brakes and pneumatic cranes!)

[warriorpoet]

This answer I'd like to see :)

Although.. mayhaps it has to do with the fact that the bridge has a smaller diameter than the tubing used between your serial pumps? However, in a closed system I think all fluids move at the same velocity with equal pressure throughout (hence hydraulic brakes and pneumatic cranes!)Equal velocity, yes, equal pressure, no. I think this is why we have these dual tops to begin with- to extend the favorable part of the PQ curve out further into our loops as flow remains constant.

...or do I have this cattywumpus?

[warriorpoet]

OT: FWIW, the EK GTX280 block is a sexy piece o' art.