Quote:
Originally posted by MadDogMe
It's nice to know that there's another performance option. Makes me wonder how much of WW was impingment and how much was micro~channels...
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The answer is that it's quite naturally, both.
The degree to which one "dominates" is dependent on the flow rate, as is theorised by Les and his base-plate thicknesses. At higher flow rates (around 4lpm and up) the jet impingement aspect starts to become the primary effect at play, below that the mini-channels are the primary effect as heat is spread out and up the walls more. Both effects are always working in unison.
This is something that I've re-established with the Cascade block and different sized holes in the base plate and the amount of copper between the cups, which effectively are the cooling equivalent of the fin walls in the White Water.
Too much copper and the jet impingement doesn't have enough total surface area to compensate for the spreading resistance of the copper cup walls. Too little copper for the walls and the heat that the jet impingement isn't dealing with (adequately) can't spread easily enough to the cup walls to be cooled.
The jet impingement action has it's limitations. Given enough flow and jet velocity the need for fin walls can be effectively eliminated, but not with the pumping pressures we're used to dealing with.
Of course, extra pumping pressure goes hand in hand with extra pump heat, and so we have to make a trade-off here as well. It's never simply a matter of maxing any one aspect because this always comes with its own separate issues. It's all a complex juggling act that even now I'm still learning the many facets and balances thereof.