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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)."
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
Actually read the article, the spinning heatsink is attached to a base plate. It DOES NOT sit directly on a CPU die.
There's an article?!
It's OK. Not even the editor read the article, or they would have seen it was from 9 months ago.
"National Security is the chief cause of national insecurity." - Celine's First Law
I would suggest that one of the major reasons that US still uses Standard measurements in engineering has to do with "network effects" that date to the two world wars. During the second world war, European factories were heavily bombed and after the war they needed to be re-tooled. In contrast, American industry tooled up for the war, (using standard measurements) but was never bombed, leaving a surplus of high quality tools, many of which are still serviceable to this day. When you are making a new mill or lathe, it doesn't really matter whether it is calibrated in standard or metric, but re-calibrating an existing machine for a different system of units is very costly.
On a typical manual mill, for example, turning the traverse handwheel a complete revolution moves the table by an integer number of thousandths of an inch (usually 100 or 200, which are 2.54 and 5.08 mm). To operate the mill in metric units requires either that the operator remember that a revolution is 2540 micrometers (awkward) or rebuild a significant precision part of the machine (the leadscrews and leadscrew nuts). You might think that this wouldn't be a problem with CNC mills, but many use stepper motors to turn the leadscrews. Those stepper motors might have only 200 or 400 steps per revolution (giving a resolution of 1 to 0.25 mils, or 0.0254 mm to 0.00635 mm) which can make it inconvenient to use metric units.
If that weren't bad enough, collets (basically an adapter to hold the "bit" in the mill) come in standard sizes to hold mills (what you call a mill "bit" used on a milling machine. yes, it is confusing) of standard sizes, which are typically fractions of an inch on US equipment. When you are machining a piece of metal, the finite diameter of the mill it usually important. The accessories that go with a milling machine can easily add up to more than the cost of the machine itself. So, to really operate a mill in metric units in a convenient way, you'd also need re-purchase all the little parts that go with the mill.
Someone is probably going to reply that these issues don't apply to modern CNC tools. I'm not familiar with those, but the point is that there are a significant number inexpensive and serviceable tools in the US that can only work with metric units in a very awkward way (or at great expense).