> Temperature delta can be increased by just putting devices in series.
Yes, but depending on efficiency this can scale quite horribly. Multi-stage Peltier coolers, for example, used to be absolutely horrible in yhis regard - a two stage device would need to dissipate 100W at the high temperature side to provide just 1W at the cold side. (I remember doing the math for a project around 2016, don't know how much better it is these days.)
The elevated temperatures of the overheating components are such that fluid flow, not temperature difference, is the thing to go after, and it also has the advantage of being much simpler than adding a whole refrigeration cycle.
These problems start to read like problems from nuclear power, where sufficiently uniform flow is a huge deal so that various materials aren't compromised in the reactor.
No doubt about it. Pumping megawatts into any box will bring up cooling issues. I read a quote from the director of operations or some such at Cray Research back in the mid-1990s: "Basically, I run a refrigerator company."
> That's inaccurate and doesn't actually make sense.
You want a steep temperature gradient at the limited chip surface to maximize heat flux. Pumping a liquid with high heat capacity to it steepens the gradient where you need it. Cooling the liquid on the other hand can happen over a much larger surface area with shallower gradients and thus lower heat flux.
Note that while the heat pipes in air coolers do use convection they do so passively, liquid cooling solutions are active.
This is completely, completely wrong. Really honestly confused nonesense. Supercooling lowers the ullage pressure, if anything increasing the need to pressurise (self or otherwise), because the self pressurisiation (the vapour pressure) is lower. So you have to do additional work to feed the pumps. The only reason to supercool is to increase the density. Your comment is quite incorrect.
I think they're referring to the heatsinks _in_ the air conditioning and refrigeration systems. The higher efficiency of the cooler itself would allow these devices to operate more efficiently.
> how fast you can move heat into the working fluid and how fast the radiator can move it out of the working fluid.
Nitpick: "working fluid" here implies that cooling has to involve a liquid. But there are solid-state (e.g. peltier) CPU coolers, which of course have no "working fluid." They suck, but they exist!
(I think the suckiness of the existing peltier CPU coolers might be due to their small size, though. If you gave one of them as much solid-state thermal mass to work with as a water-cooling setup has fluid thermal mass, it might be rather efficient, for the same reason a chest freezer is efficient.)
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