Water Cooling Theory Thread

[kommando]

Hey all i decided to make this thread so everyoen can post their theories of watercooling and some examples of it.

Ill post what i think tommorow.

[kommando]

What i think - If a pump is moving liquid at (a)10 litres per hour and another at (b)100 litres per hour. The actual temperature of the cpu or whatever is been cool will be the same because pump (a) is spending more time in the radiator so its being cooled better.

Would this be true?

[InvisGreenMan]

no

[kommando]

But ones spending more time in the rad so its getting cooled just as much as it was spending time in the waterblock...

Just 10x slower or faster.

[Çhrist0ph]

well, there's only one way to find out....DO IT!

[kommando]

Will do, need to find a ty pump first.

[InvisGreenMan]

I'll bet you your rig(s) that the better pump gives better temps. You can't break laws of thermodynamics and physics.

[h0ok3r]

i think that you need at least a moderate flow, if your flow is utter crap then it'll effect your temps cos the water might stay in the rad longer,
but ill mean that the hot water will stay longer @ your cpu

So the slower yur pump the bigger the temp difference in your WC sys will be.
[edit]
i'd like to ad to that, that the water kan only cool down to room temps in a rad, and the longer its in your rad the slower it'll cool down since the temp diff is less high. But your Cpu has unlimted heating capablity so a slow flow i think will be ineffective\inefficient....
[\edit]

I think the difference between a high and a moderate flow wont differ much in temp, @ least not singnificant....


just my 2 cents

h0ok3r

[freecableguy]

Pump laws and thermodynamics are your friends. Suffice it to say that you will find enought about this on the internet to read for many lifetimes. Go learn.

[Creig]

Just like everything in life there are too many variables to be able to boil (so to speak) liquid cooling down to a simple A + B = C formula.

You can either go large volume/low pressure (1/2" lines, eheim) or low volume/higher pressure (1/4", 3/8", Koolance). Then you have the total volume of water in the system, how long the lines are, how many total degrees of bend are in the lines, what type of waterblock, how many waterblocks, the overall flow resistance of the blocks, radiator size, fan size, fan speed, total amount of heat to be dissipated, average room temperature, average case temperature... and so on and so forth.

Your best bet would be to read as many threads as possible concerning peoples choices in liquid cooling, match it up as closely as you can to your system and go from there.

[Piper]

New to these forums, but not to this subject.

First off, just like in most everything else in life, balance is good, you can get an over-powered pump and actually hurt your cooling effort. But as a rule, high flow rates produce better performance primarily because moving the water through the WB fast does two things. It does a better job of disturbing the laminar layer of hot water next to the surface of the base plate, and it keeps the average temp of the water flowing through the WB lower. The greater the difference between the average water temp flowing through the WB and the temp of the base plate the better transfer of heat you will have.

As for the radiator, it will transfer heat as fast as it can, and you don't have to worry about moving the water through it too fast, that's pretty much impossible anyway. A bigger issue is simply having a big enough radiator to begin with. More surface area means greater cooling efficiency, but you have to watch out for the effects of having too large a radiator as that will impact your flow rates.

Again, balance it all out and remember that others have probabaly played with most of the different combinations of gear, you just have to check around for the info.

Last thing to remember, unless your water cooling TECs, which greatly increase the heat burden, then any decent water cooling setup is perfectly capable of doing what you need it to do, unless your just trying to compete with everyone else for some world record CPU temps.

[Prandtl]

Originally posted by kommando
But ones spending more time in the rad so its getting cooled just as much as it was spending time in the waterblock...
Just 10x slower or faster.

As other said, this isn't true, no matter how high your waterflow is, there will always be water in your rad and even more if you look at water as packet, each packet will spend the exact same time (per minute) in the rad NO matter what the flow rate is.
Cathar (the man behind the WW and Cascade, the wb, not phase-change) had a very good way of explaining it in a thread @ procooling.com , but here is a quote from that thread:

The best way to think of it is like this.

In a fully bled system, name any time in which there is no water in the waterblock?

ie. there is no such time.

Therefore there is water in the block all the time. Regardless of the flow rate, the water spends the same amount of time in the block.

If we want to talk about packetised concepts, think of a car running around a circular race track. For an example, let's assume that the waterblock is a 60m (meter) stretch of road, and the racetrack is 600m long.

How many times per hour is the car inside the 60m section, and for how long?

If the car travels at 10m/s, it's in that 60 meter stretch for 6 second. In an hour the car travels 36000m. The racetrack being 600m long, means that the car go around the track 60 times in an hour. The amount of time spent in the 60m waterblock section is 6 seconds x 60 = 360 seconds.

If the car travels at 20m/s, it's in the 60m stretch for 3 seconds per lap. In an hour it travels 72000m, and will have completed 120laps in that time. 120 x 3 = 360 seconds.

The car has spent exactly the same amount of time in the "waterblock" stretch, regardless of its speed.

[saratoga]

Originally posted by kommando
What i think - If a pump is moving liquid at (a)10 litres per hour and another at (b)100 litres per hour. The actual temperature of the cpu or whatever is been cool will be the same because pump (a) is spending more time in the radiator so its being cooled better.

Would this be true?

Water spends 3600 seconds in a radiator every hour no matter how fast or slow its moving.

[kommando]

OKay that theory has been proven wrong.

Myyy bad.