Dual Pump Idea

[jlrii]

I was playing around with an idea similar to this a 'lil while back. But what I found....by working the numbers only (which is NOT a substitute for experimentation ala BillA) is that you make no gains from having more flow through the rad. I have yet to see if it may work the other way around, with more flow through the block (gotta change the Excell sheet I made up to calculate the balance point). The sheet calculates water temp on a pass by pass basis at the block and rad, then calculates the mixed water temp supplying the block...repeat repeat repeat....usually took about 4-500 loops to balance out. Result....well with the blocks I had detailed enough info on I got slight losses, never any gains. I'm in the process now of rebuilding my rig with components that I have enough info on to play a little more with it.

[LPorc]

Originally Posted by Ares

essentially your using a venturi design where flowing water at lower pressure sucks water from the resevior with it. pulled through by the 2nd pump, and shot through multiple radiators.

Ares, if both pumps were pulling from just the resevoir as initially presented, wouldn't any pump suction already be split among the resevoir inlets?

I'd think the mixing of the waters in a resevoir would be ok unless the resevoir was very large or the inlets were placed very poorly in relation to the outlets. If you think about the flow scenario, basically there'd be 2 pumps putting essentially 3 times the usual flow through the resevoir, so the resevoir will be nicely turbulent unless it is quite a bit larger than what seems typical.

As to comments by others, I'd think the water moving through the radiators twice as fast as the cooling loop shouldn't really make much of a difference, though. The radiator will basically shed just as much heat as delta-temp and airflow will let it, so I'd think little gain unless the radiator was already overkill for the setup, then running twice the flow through the radiator as the cooling loop would at best be less than running two radiators in series.

And here's a musing for all those who love to say that delta-tempature between coolant and ambient makes radiators more efficient, I don't see how that's possible. Here's a thought experiement of why: for a constant airflow through the radiator, a constant flow rate, and a constant ambient tempature, graph your radiator input tempatures x more than ambient, and output tempatures y more than ambient. Wouldn't (x-y)/x be the real measure of efficiency? So for the premise to be correct as x increases y approaches x, so a little postage stamp radiator could cool infinitely super-heated water to ambient in one pass.

I would suppose the best-case scenario is then that the radiator will reach a point of load where it sheds a constant (x-y), which would mean it's all about the ability of the air to remove heat from the radiator. So essentially all water cooling accomplishes is moving the heat from the cooling blocks to a big heatsink (the radiator).

[lolito_fr]

This might be slightly OT...

Its an idea I had based on my limited experience of water cooling, where two pumps might be quite useful.
In this case, one pump is driving the "main" cooling loop (CPU, GPU, rad), and the second smaller pump would drive a "secondary" low flow circuit to cool lower power components such as hard drives, northbridge, mosfets, PSU...

The main loop would be 1/2" or 3/8".
The second loop could use 1/4", which has the advantage of being that much more flexible

Excuse the lame paint hack of your wonderful diagram

[jlrii]

As to comments by others, I'd think the water moving through the radiators twice as fast as the cooling loop shouldn't really make much of a difference, though. The radiator will basically shed just as much heat as delta-temp and airflow will let it, so I'd think little gain unless the radiator was already overkill for the setup, then running twice the flow through the radiator as the cooling loop would at best be less than running two radiators in series.


While i'm not sure if Foxgguy wants to do this for the same reasons I can say why I thought it might work b4 playing with the numbers. It is not the added flow through the rads I thought would add some performance, it was the added PASSES through the radiator. Granted added flow thru a a rad produces practically no change in it's C/W. But what happens if the water makes 2 passes through the rad for every one through the block? Will "re-coolling" ,if you will, the water in the loop add any additional performance? As far as I can tell at this point that answer would be no. I was picturing that added passes through the rad would act like having a second rad of about 1/2 the size of the original in series with the first...which it does. But the gains there appear to be outweighed by the gain in C/W at the block that could be made by having all of the flow go through it. This outcome was based on calcs alone and is not by any means proven with experimentation. What I am working on now is rebuilding my system with components that have known C/W
and flow curves curves to test it for real. The way I am going to set it up will allow me to alter the flow rates through the rad or block which will allow me to see if any gains are available from this method or it's inverse (allowng the block to recieve more flow than the rad). Intuition alone tells me that aproach probably won't present gains either.... I will do some calcs b4 I complete the project to estimate what may happen. Why bother doing it?......just fun to play with ...thats all.

[BillA]

if you guys used some data (and there is enough 'real data' out there to be able to gin up some bogus values for calcs)
and calculated the Log Mean Temperature Difference (LMTD) of your rads (air side also)
the efficacy and cost/benefit ratio of your different scenarios can be easily evaluated

but then there would be no 'discussion' I guess

[jlrii]

Originally Posted by unregistered

if you guys used some data (and there is enough 'real data' out there to be able to gin up some bogus values for calcs)
and calculated the Log Mean Temperature Difference (LMTD) of your rads (air side also)
the efficacy and cost/benefit ratio of your different scenarios can be easily evaluated

but then there would be no 'discussion' I guess

Hmmm......I thought I just said I did that....jees....you are grumpy LOL

EDIT: Igotta admit I took the easy way out and used AMTD...and yes it does throw the calc off somewhat.

[LPorc]

Originally Posted by unregistered

if you guys used some data (and there is enough 'real data' out there to be able to gin up some bogus values for calcs)
and calculated the Log Mean Temperature Difference (LMTD) of your rads (air side also)
the efficacy and cost/benefit ratio of your different scenarios can be easily evaluated

but then there would be no 'discussion' I guess

Heh heh... If I knew how to do any of that, I wouldn't be lurking here trying to pick up knowledge through osmosis! I just write code and poetry, this physical sciences stuff is all new to me. Even my thought experiment is more of a philosophical argument, a thinly veiled Socratic monologue (not a dialog as nobody commented on it). Maybe I should buy a book. Any recommendations?

[Joe Camel]

i wish i could calculated "the Log Mean Temperature Difference (LMTD)" of all this stuff. then i wouldnt be learning this with the trial and error method. i also wouldnt be asking the questions here, id be answering them

[BillA]

google is your friend
then start looking up every word in the definition of LMTD which is not clear
a bit tougher than being spoon fed, but it works

[Joe Camel]

baby wanna be fed

good point BillA...

i just wish i had this hobby when i was in collage (soooo many years ago) i might have payed (more) attention in math/physics class then...(note to all the young'ens out there!)

guess ill be testing the "you cant teach an old dog new tricks" theory next

[BillA]

lol, little sympathy here Joe,
I'm 58 and 4 years ago had never heard of WCing a computer;
all depends on the extent of one's interest

[myv65]

Originally Posted by unregistered

lol, little sympathy here Joe,
I'm 58 and 4 years ago had never heard of WCing a computer;
all depends on the extent of one's interest

You're not often blatantly wrong Bill, but this time you are. If it all depended purely on one's interest, Ben would be king of the watercoolers. Much like you need a good pump, block, and radiator to create a good system (as opposed to one item being crap and trashing the entire thing), it takes both interest and ability. A good engineering education can serve as an immense leg up on the matter, but without ability you'd be hopelessly lost.

[Joe Camel]

w00t!! i made ol' grumpy LOL! even if the 2 loop dosnt work, it was worth it for that!

parts update: the poly-top WW is soon to be replaced with a Cascade!
so ill do a "real life" WW vs Cascade, then the 2 loop vs one. and ill post my (not so scientific) results here (too).

PS i thought i'd get A LOT more than i did. guess y'all arnt that bad here

thanks for the input

[BillA]

Originally Posted by myv65

You're not often blatantly wrong Bill, but this time you are. If it all depended purely on one's interest, Ben would be king of the watercoolers. Much like you need a good pump, block, and radiator to create a good system (as opposed to one item being crap and trashing the entire thing), it takes both interest and ability. A good engineering education can serve as an immense leg up on the matter, but without ability you'd be hopelessly lost.

oooof, gut shot
the oldest trap, assuming that others are the same/similar
no argument; certain specific abilities are required to become a practitioner,
lesser obviously to come to a basic understanding - but still not for deadheads
(I should be more mindful of 'ability' given some huge difficulties in 'explaining how to interpret a graph')

but Dave, also of consideration is motivation
I'm operating under the assumption that I will have more success by pushing people towards the sources of info, rather than by telling them how difficult the subject matter may (will !) be

I would emphasize your statement as follows:
"A good engineering education can serve as an immense leg up on the matter, but without ability you'd be hopelessly lost."

[Les]

Originally Posted by myv65

You're not often blatantly wrong Bill, but this time you are. If it all depended purely on one's interest, Ben would be king of the watercoolers. Much like you need a good pump, block, and radiator to create a good system (as opposed to one item being crap and trashing the entire thing), it takes both interest and ability. A good engineering education can serve as an immense leg up on the matter, but without ability you'd be hopelessly lost.

Sweet, but the side swipe at Ben?
Bill I respect.
Ben comes across as a genuine person,who bows to reasoned argument with grace.

[BillA]

Les,
I think Ben was cited merely as an example where great interest was/is limited by his education/ability. (specifically which was not specified)
Ben's achievements have always been constrained by his understanding, he is improving - but his lack of a sound technical education slows his progress.

The point I would make is that it should not be necessary to argue with Ben.

[Les]

Originally Posted by unregistered

The point I would make is that it should not be necessary to argue with Ben.

Point accepted.
However, why not use
http://my.coolingzone.com/#/forums/wwwthreads.pl .

[myv65]

My apologies if it offends Ben, as that was not the intent. Bill has deduced my meaning. Ben has more enthusiasm than anyone else I know and has progressed mightily from his first days here. Had his education centered on engineering, much of his struggles would not have occured. His learning watercooling technology is akin to me learning Spanish. I have no gift for foreign language, but my wife has a degree in Spanish and my three year old can converse reasonably well in either language (running circles around my understanding). I am getting better, but can not pick it up with near the speed of my daughter.

[Joe Camel]

ahhh now thats more what i expected here @ pro (flame) cooling!


yo BillA, sup with the "deadhead" comment? (some reference to the pic of me wearing a "dead" Tshirt?)


how the hell does all this "ripping" on each other help us (me) learn about water cooling?

im not here to prove how smart (or dumb) i am!!
im here to learn from those who know (more) and pass on what i "know" to those who know less.

you can take all these "gut shots" and shove it up your 1/2" ID hoses! ...flame on...

[Les]

Joe Camel
Many of us have posted data or theoretical considerations.
Suggest a search of posts by Les,myv56,and unregisted may help.

[jaydee]

Originally Posted by Joe Camel

ahhh now thats more what i expected here @ pro (flame) cooling!


yo BillA, sup with the "deadhead" comment? (some reference to the pic of me wearing a "dead" Tshirt?)


how the hell does all this "ripping" on each other help us (me) learn about water cooling?

im not here to prove how smart (or dumb) i am!!
im here to learn from those who know (more) and pass on what i "know" to those who know less.

you can take all these "gut shots" and shove it up your 1/2" ID hoses! ...flame on...

Then shut up, start reading threads and learn something.

[Joe Camel]

i have read. i have learned. i will continue to read. i will continue to learn.

i come here with an open mind. i dont spew my theories as law. i dont flame those who are (actually) trying to learn things. im not asking to be spoon fed. im asking for some guidance.

Punching you child for doing something wrong dosnt accomplish one thing. explaining to them what and why it was wrong and why they might want to do something different next time "might".

after reading (and learning) your 11 page thread,(http://forums.procooling.com/vbb/showthread.php?t=6385) i can say 1 thing: we ALL seem to be learning. every theory seems to have an exception and every setup is different. with this in mind and the fact that my "dead"head dosnt like math, i guess ill stick to the trial and error method.


its REALLY too bad a (hopefully) troll like Graystar gets 3 pages of y'all bending over backward to try and help, and i get told: "shut up, start reading threads and learn something"


oooof, "head" shot

[Cathar]

Don't take it to heart Joe_Camel. The guys here really are helpful. You just have to show that you're willing to spend some effort. They'll rarely spoon feed anyone, which I typically attribute to the style of education that occurs at University. Being spoon-fed is easy and lecturers always held a certain amount of contempt for students who were merely sponges. The interesting students were the ones who go out of their way to investigate something, to show independent and inspirative thought. Don't be disheartened though, there's a lot to read and take in.

Sadly Graystar had a number of us fooled for a while there. He looked like someone who was capable of independent thought, but it merely turned out to be an illusion.

[Joe Camel]

sweet....Cathar typed my name.....and billA has responded to me too...im so

i was really just putting the guilt (flame) on y'all with that last post
(oooof, "head" shot)


dont worry Cathar, im bound and determined to test this theory out. (im 1/2 way there)

like i said we all seem to be learning, so ill check this theory out and see if there are any exceptions to be found.

feel free to add some guidance. (like: other than my MBM temp readout, i dont have any way to check temps...(add helpful hint here)


i hope i passed the audition

[fhorst]

Originally Posted by Joe Camel

w00t!! i made ol' grumpy LOL! even if the 2 loop dosnt work, it was worth it for that!

parts update: the poly-top WW is soon to be replaced with a Cascade!
so ill do a "real life" WW vs Cascade, then the 2 loop vs one. and ill post my (not so scientific) results here (too).

PS i thought i'd get A LOT more than i did. guess y'all arnt that bad here

thanks for the input

Where did you get that cascade!!!