Quote:
Originally posted by hara
Direct die cooling has hit the wall. This is because water has a too low SHC to keep up with that small area and high heat output. It may regain acceptance if another coolant is used.
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Data? SHC??? Water has a specific heat capacity over TEN TIMES that of copper (Water: 4180 J/(kg*K) , Copper: 390 J/(kg*K) src:
http://yesican.yorku.ca/home/sh_table.html ) . SHC is irrelevant to continuous cooling systems anyway.
Look at the pdf I
linked to earlier:
http://www.mit.edu/afs/athena/org/m/...ms/paper12.pdf
You will notice they even compared direct-die microjets to microchannels (REAL microchannels) and found microjets to be "more effective because they can remove larger heat fluxes at lower surface chip temperatures."
And their results are using flow rates measured in
single digit milliliters per minute. "Higher flow rates... will facilitate even higher heat flux removal and heat transfer coefficients." If even 1 LPM can be attained using these microjets, you can decrease their measured C/W by at least one order of magnitude.
I think there should be no doubt that direct-die microjets can have much lower thermal resistance than any heatsinks or conventional waterblocks.
The question now is how to engineer one that will work.
edit: presented -> linked to. Ben: "present" as in "To offer for observation, examination, or consideration." Do they use a different dictionary in Texas?