watercooling ID smaller is better?

[tony4704]

I was talking with a guy from frozencpu and he is telling me that with my exos2 system I would be better off using 8mm ID tubbing then 9.525mm (3/8ID). I can only assume then that because its smaller, less volume, more flow will be achieved. What do you guys think about what he said? Thank you.

 

[themusgrat]

No. Larger ID is better, because it allows for more flow, unless the pump is really sucky. I guess if your pump did like a gallon an hour, smaller ID would be better, but not with any half decent one. He might be saying that though because your system is 3/8 native, and you won't have to use adapters.

 

[GalvanizedYankee]

Do you think FrozenCPU is telling you a lie?

Have you looked to see what the manufacturer of the pump reccomends?

I have never set-up a w/c system but because of my extensive automotive background I will say, bigger is not always better. Why? Because vane type water pumps work their very best when working against some resistance on the return line side. This keeps any cavitation at a minimum near the impeller hub and through out the system.

If I were an OCing mad man here is what I would do. The discharge would be hooked up to a manifold, this would serve both the VGA, CPU and what ever else got coolent. All return lines would come back to their own manifold. At this return manifold each line would have it's own shut-off valve. With these valves coolent flow to the various heat generating componets could be tailored to the need of each.


...Galvanized

 

[Parkre]

Well, Larger is better in a sense. Because of the the larger OD, the boundary layer formed will allow for better flow. However, some case can't accomodate the hose..especially if you are trying to watercool everything (cpu,gpu, chipset, ram).

Another problem is the turns (elbows). 10:1 ratio is used for turns if you really want to reduce pressure loss. So if you had a 1/2 hose, the radius of the turn should 5 inches. If you had 1/4 hose, you would only need 2.5 inches radius. (This ratio is what we use for Fluids class for ideal situations, it's just a rule of thumb we went by.)

Maybe the guy at FrozenCPU thought you were talking about a pump. Or maybe the pump in the system isn't really powerful enough to move a lot of volume.



For future reference, there are a LOT of things to consider when trying to design the perfect setup. The greater the temp differences between the water and the cpu, the boundary layer flow across the water block(turbulant is better), the surface area of the fins in the water block, the length of tube, the amount of head pressure loss across the system, the radius of turns (elbow), amount of turns, the list goes on....

http://www.systemcooling.com/ does a very thorough job of their reviews when it comes to systems and waterblocks.