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Compressor-Free Refrigerator On the Way
Iddo Genuth writes "Scientists from Penn State University are designing the future of refrigerators and other cooling devices through magnetic field refrigeration. The investigation pertaining to electrically induced heat effects of some ferroelectric polymers might one day replace electrically powered refrigerators and their compressors and coils. The researchers are focusing on ferroelectric polymers that exhibit temperature changes at room temperature under an electrical field. The same technology might also find its way into computers and other devices in the future, making them run cooler without complex cooling mechanisms."
http://tech.slashdot.org/article.pl?sid=08/08/10/2237223 And the first summary had more details.
$_ = "wftedskaebjgdpjgidbsmnjgcdwatb"; tr/a-z/oh, turtleneck Phrase Jar!/; print
Yes, there are other ways to cool without a compressor, but they are in a lot of cases nowhere as energy efficient as the tried and true way of compression/evaporation. For example, peltiers can do cooling, but they take a lot more power and produce less temperature differential than the standard methods.
This is a dupe from August 10th. Sorry guys.
Spelling mistakes, grammatical errors, and stupid comments are intentional.
now it just needs to be atomic and fit in the palm of your hand :-)
Did you mount a military-grade, variable-focus MASER on an unlicensed artificial intelligence?
Where's my reverse microwave oven?
Yeah... you go ahead and use magnets to "cool" your computer. Let me know how that works out. For our younger readers: holding magnets close to food doesn't turn the food into a useless brick, but holding a magnet near a computer will probably do that.
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This could feasibly be used to make a practical air conditioner by having a segmented disk shape block that allows air to pass through.
Outside air would pass through one half of the disk that is currently energised (the electric field orders the polymer and thus releases heat).
The inside air would pass through the other half that is currently not energised (the relaxation of the electric field allows the material to absorb heat).
The disk rotates with segments shifting between the outside / inside halves, the electric field is applied by a simple electric comutation.
This is not a true "no moving parts" system but it has the potential to be an order of magnitude quieter than the current air conditioning units.
See my journal for slashdot ID's by year. Mine created in 2005. http://slashdot.org/journal/289875/slashdot-ids-by-year
Vendors like Coleman have been selling solid-state peltier effect portable refrigerators for camping use for years.
This technology is of great use even today in the lab, but will most likely take much longer to bring to your kitchen. Currently, the magnets required for the heat transfer need to be cooled to subzero temperatures anyhow.
The Wikipedia article on Continuous Adiabatic Demagnetisation Refrigeration does a pretty good job of explaining this.
Also keep in mind that the magnetic fields used in this cooling method requires several Teslas to efficiently transfer heat. Aside from being difficult to produce, shoddily made units could basically make all your other electronics inoperable.
If I had a nickel for every time I had a nickel, I'd be richcursive!
They've been around for while. Any standard fridge can be made to work without a compressor (read: "pump") just by using a pilot light (even just a candle) at a low point to get the coolant to circulate up and around.
albert einstein and leo szilard had one of these patented in the 20s, somebody in germany made them for a while. very, very old news indeed.
if this is supposed to be a new economy, how come they still want my old fashioned money?
What I want to know is how this is affected by my huge collection of fridge magnets?
Will one more souvenir magnet from a trip cause my milk to spoil? Or will I have to thaw my mustard? :-P
Cheers
Lost at C:>. Found at C.
..and so on, like so many tech advances out there, but if you want an alternative *now*, you can get a DC powered Sundanzer refrigerator or freezer and power one of them from a single solar panel. They are conventional compressors, but are built loads better with much more insulation than most other units. I don't need either now, a fridge or freezer, ours are both still pretty new and functional, but next time I need a new one, that's going to be it.
whatcouldpossiblygowrong?
...replace electrically powered refrigerators and their compressors and coils. The researchers are focusing on ferroelectric polymers that exhibit temperature changes at room temperature under an electrical field.
So they're going to replace electrically powered refrigerators with refrigerators that are powered by electricity?
You never really know how close to the edge you can go until you fall off.
it's hot!
Better order a new wife ;)
First off, the way you want to make the stuff is as a thin plastic film. Aluminize both sides, and you can apply the voltage very easily. Fold it in half, and the high voltage electrode is sealed inside the plastic, so you're less likely to electrocute people.
Next, roll it up, except keep a gap between each layer so you can blow air through the roll. This will need something like the middle layer of corrugated cardboard -- making little air channels against the film.
Finally, you want a bellows, to pump air back and forth through the roll. Syncronize the voltage with the bellows, but out of phase, and you'll get a heat pump, which works like this:
The great thing about this is that if you use a long roll of the stuff, you can make a temperature difference much greater than the on vs. off temperature gap. Each segment of the roll does the same refrigeration trick in parallel, but temperature difference is wired up in series, so your the temperature of the fridge is limited only by practical matters like leakage.
Note that you don't even need to pump air all the way through the roll; as long as the air is moving back and forth, you'll get the refrigeration effect.
These are no more "on the way" than the ultrasonic refrigerators publicized a couple years ago. In both cases an effect is being played with. The technology necessary to produce a viable refrigeration unit will, in both cases, have to wait until they're done fooling around with the lab table versions.
"I may be synthetic, but I'm not stupid." -- Bishop 341-B
With Global Warming isn't refrigeration going to be moot. Just put your beer outside :D
I've nothing of importance to say, now go away before I taunt you with a second sig!
I bought a USB-powered compressor-free fridge several months ago, and it works great: http://www.thinkgeek.com/computing/accessories/96b3/ Move along, nothing new here.
The definition of a liberal: I may disagree with what you have to say, but I'll fight for your right to say it
Done. Okay, not on the computer I'm currently using, but I've done this experiment before. Unless you've got a hellaciously-strong magnet, you simply won't be able to effect the proper functioning of a microchip with a magnetic field.
As other people have mentioned, there are very powerful magnets inside the hard drive, and as it turns out, the magnet isn't likely to stick to anywhere other than the voice coil or spindle motors, where it won't do any damage to the recording media.
This table:
http://en.wikipedia.org/wiki/Coercivity#Experimental_determination
shows that the coercivity of fridge magnets and hard disk media are approximately the same. In order for a fridge magnet to induce a change in the magnetic field of a HD platter, it'd have to practically be resting right on the platter itself.
I wonder if the contents of the fridge will become polarized?
How hard would it be to eat cabbage that attracts to your fork? Or drink a beer that keeps trying to stick to your washing machine...