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Sandia's Floating, Dust-Free, Spinning Heatsink
An anonymous reader writes "Sandia Research Laboratory believes it has come up with a much more efficient solution than heatsink-fan cooling a CPU that simply combines the heatsink and fan components into a single unit. What you effectively get is a spinning heatsink. The new design is called the Sandia Cooler. It spins at just 2,000 RPM and sits a thousandth of an inch above the processor. Sandia claim this setup is extremely efficient at drawing heat away from the chip, in the order of 30x more efficient than your typical heatsink-fan setup. The Sandia Cooler works by using a hydrodynamic air bearing. What that means is when it spins up the cooler actually becomes self supporting and floats above the chip (hence the thousandth of an inch clearance). Cool air is drawn down the center of the cooler and then ejected at the edges of the fins taking the heat with it. And as the whole unit spins, you aren't going to get dust build up (ever)."
It spins at just 2,000 RPM and sits a thousandth of an inch above the processor
What could possibly go wrong? Seems like a pretty tight tolerance with all the vibration that could occur in a server room.
I'm reminded of the rotary engine, used in some WWI aircraft. The crankshaft was stationary -- attached to the plane's firewall -- and the entire engine block, including the cylinders, rotated around it. (The propeller was attached to the engine block.) In this way, no flywheel was necessary (the block was its own flywheel), saving weight, and the engine was cooled naturally, by the air flow over the moving cylinders. I don't know how the engines were balanced.
In a similar manner, the Sandia Cooler moves the heatsink through the air, rather than the air through the heatsink. It's solving a different problem, but I've always been fond of contrarian thinking like this.
http://hardware.slashdot.org/story/11/07/12/1348243/the-fanless-spinning-heatsink
Can we get some new editors??
But...all my fans get a layer of dust on each fan blade. What are they doing differently that will stop this?
Aah, change is good. -- Rafiki
Yeah, but it ain't easy. -- Simba
Given the possibility of dynamic movement of a laptop during its use, will the Sandia Cooler work inside of a laptop?
Maybe I just didn't get the message, but what draws heat away from the die itself? This setup probably does away with thermal paste and similar junctions...
The other thing is that hydrodynamic bearings are only self-supporting and quasi-frictionless after a threshold RPM is reached. Before the whole setup is spinning fast enough for hydrodynamic effects to take over, it's going to grind against the chip die, and unless they came up with something good, it's going to destroy it on startup...
Hyperbole: I use it liberally!
Turn it off? Who turns their computers off? Uptime: 3481 day(s), 6 hour(s), 33 minute(s) :P
According to the .pdf linked on the press article, it spins at 5,000 RPM.
Spinning a heat sink that weighs several ounces take a much more powerful motor than a plastic fan. I'd expect it's a to harder on the bearings (i.e. less reliable), and requires a lot more power than a traditional heatsink/fan setup.
My CPU normally runs around 140 degrees so at 30x more cooling I should be well into the -4000F range!
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Dear researchers, please notice how dust will cake and adhere to spinning things. Ask the airline industry how dust can cake on even turbine blades.
It's not dust free, please take the marketing people out back and beat them with a sack of doorknobs.
Do not look at laser with remaining good eye.
If your working fluid is moving fast enough, it stops mattering how conductive it is. The Reynolds number starts to dominate all the heat transfer coefficients. The problem with cooling is always the boundary layer, where the fluid stagnates and acts as an insulator. Sandia's found a way to minimize the boundary layer by shrinking the gap between heatsink and fan. Props to them.
My fans spin pretty fucking fast, and yet, they have dust on them (and cat hair, got to love the cat hair).
Let's go for a real world test. Put the heat sink in my computer, and let's see what happens.
Be seeing you...
When your system isn't online and you're only using it for a dedicated task, you quite often don't upgrade shit if it's stable.
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
See The fanless heatsink: Silent, dust-immune, and almost ready for prime time, and an interview with the inventor.
Disbelief of the dust-immune property of this cooler is addressed in the first question of the interview:
Jeff Koplow: I did not mean to imply that there is literally no dust fouling; some dust accumulation eventually becomes visible to the naked eye on the very leading edge of the blades. The point is that dust fouling is reduced to such a large extent that we are unable to detect any degradation of cooling performance operating the device in a relatively dirty environment over an extended period of time. Thus for all intents and purposes the dust fouling problem has been taken off the table. In contrast, with conventional CPU coolers, eventually the entire heat exchanger surface becomes entombed in dust. I suppose there are some applications in which computers are operated in extremely dusty environments that might be too much for the heat-sink-impeller. This is common sense. In trying to figure out a way around the longstanding problem of CPU cooler dust fouling, I was thinking in terms of residential and commercial environments where the vast majority of PCs are found.
Once again, it is disappointing how many people so yearn for the status quo, when presented with clearly superior technologies. Not that they always pan out, but it is disheartening to see such hostility toward progress.