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Unread 06-29-2002, 10:30 PM   #82
BillA
CoolingWorks Tech Guy
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Quote:
Originally posted by myv65


There is, however, a general rule that most systems will provide a lower cpu temperature as flow rates increases.

My only real beef with designers of this stuff is that they don't do things as efficiently as possible. Given water's specific heat, you don't need much flow to get the job done. What you *do* need is high convection, aka high velocity in the block. With the right porting, you could cool the CPU with <20 gph easily. Why this matters is that it would allow smaller pumps and smaller radiators. I'll admit that the delta-T in the fluid would be higher than a system running ~75 gph, but so what? The cost, both purchased and operating, would be lower.
very lucid comments myv65

having several hundred pages of obsessively detailed measurements, I would add several observations

while the design basis of wbs could be different, the necessary pumps to obtain the higher convection rates are hugely more expensive
I'm looking at an Iwaki mag drive gear pump that has nominal 'ratings' of 36 gph @ 45 psi; list over $650;
and another 'big boy' that delivers 92 gph @ 75 psi lists for $1050
(max flow, max pressure; not both together, eh ?)
continuous duty positive displacement pumps are not cheap, and never will be

the smaller rad is quite 'doable' in terms of dumping the heat (with LOTS of air/noise),
the problem lies with the resultant system equilibrium temp of the coolant
- with the present wbs, a higher coolant (inlet) temp at the wb will always result in a higher CPU temp

looking forward to your article

be cool
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