Fanless spinning heatsink - the new future of CPU cooling?

[SXRguyinMA]

http://news.cnet.com/8301-17938_105-...=2547-1_3-0-20

[diluzio91]

The Sandia cooler could finally offer the cooling efficiency necessary to allow for processor clock speeds above the current rough 3.0GHz limit.

Yes... <_< >_>... 3GHZ....

[crenn]

Interesting, is this the new 'metal based' cooling solution? (I say this because we were told about a fantastic new heatsink based on liquid metals was going to revolutionise heatsinks.... as I recall, the product didn't do very well and didn't perform that great)

[x88x]

Color me skeptical. They do at least have an interesting theory, though.

BTW, a much better article on it here:
https://share.sandia.gov/news/resour...leases/cooler/
Also a whitepaper on the technology (PDF):
http://prod.sandia.gov/techlib/acces...010/100258.pdf

[NightrainSrt4]

Just looking at it, it seems like any benefit of stopping the dead air on typical fins would be lost by the heat transfer between the base plate and the spinning plate. And if they've found a way to transfer the heat between the two plates better than the cpu to a standard heatsink, that technology could just be used to improve the standard heatsink.

[TheGreatSatan]

^Exactly

[RogueOpportunist]

From my limited "enthusiast" knowledge on cooling I see nothing about the design that would suggest any serious airflow/cooling improvement over your typical stock CPU cooler but on the other side of the same coin I see TONS of flaws, notions and concepts that seem to be "wrong".

The idea that moving metal through air is going to cool more efficiently than moving air through metal seems "off" to say the least, plus putting a thin layer of air between the base plate and impeller seems like it would be counter productive.

Call me a realist but this looks more like someone trying to cash in on a patent than any kind of technological "advancement".

[crenn]

Unless you're a master of thermo dynamics and fluid dynamics, I'd read the paper in full before you judge it.

The “heat-sink-impeller” (the finned, rotating component) consists of a disc-shaped heat spreader populated with fins on its top surface, and functions like a hybrid of a conventional finned metal heat sink and an impeller. Air is drawn in the downward direction into the central region having no fins, and expelled in the radial direction through the dense array of fins. A high efficiency brushless motor mounted directly to the base plate is used to impart rotation (several thousand rpm) to the heat-sink-impeller structure. The bottom surface of this rotating disc-shaped heat spreader is flat, such that it can mate with the top surface of the heat spreader plate described above.

During operation, these two flat surfaces are a separated by a thin (~0.03 mm) air gap, much like the bottom surface of an air hockey puck and the top surface of an air hockey table. This air gap is a hydrodynamic gas bearing, analogous to those used to support the read/write head of computer disk drive (but with many orders of magnitude looser mechanical tolerances).

Heat flows from the stationary aluminum base plate to the rotating heat-sink-impeller through this 0.03-mm-thick circular disk of air. As shown later in Figure 18, this air-filled thermal interface has very low thermal resistance and is in no way a limiting factor to device performance; its cross sectional area is large relative to its thickness, and because the air that occupies the gap region is violently sheared between the lower surface (stationary) and the upper surface (rotating at several thousand rpm). The convective mixing provided by this shearing effect provides a several-fold increase in thermal conductivity of the air in the gap region.

One important point about the air bearing is that the ~0.03 mm air gap is not maintained by using extremely tight mechanical tolerances. Much like an air hockey puck on an air hockey table, or a hard disk read/write head, the air gap distance is self-regulating. If the air gap distance increases, the air pressure in the gap region drops, which causes the air gap distance to decrease. This built in negative feedback provides excellent mechanical stability and an extremely stiff effective spring constant (important for ruggedness). Unlike an air hockey table, which relies on gravity to counter-balance the pressure force acting on the puck, the air-bearing cooler can be mounted in an arbitrary orientation (e.g., up-side-down, sideways, etc.). And unlike a computer disk drive, incidental mechanical contact between the two air bearing surfaces does not damage either surface.

[Twigsoffury]

My fractal cooler would kick its a@#

[NightrainSrt4]

A several fold increase in the thermal conductivity of the air in the gap still wouldn't put it in the league of aluminum or copper. Copper has ~16K times the thermal conductivity of air. A several fold increase on the air isn't even going to approach the effectiveness of copper. I don't know. Maybe I'm just not getting what they are trying to convey there.