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Force Fields And Plasma Shields Get Closer
one2boo writes: "I guess watching countless hours of Star Trek has paid off for Mounir Laroussi, an electrical and computer engineer at Old Dominion University in Norfolk, Va. Space.com writes: 'Laroussi has literally put plasma on the table: devising an apparatus that creates a mini-plasma inside a Plexiglas cube by passing an electric current through helium gas via specially calibrated electrodes.' This advance in 'Plasma Shields' will allow the shielding and cloaking of satellites and spacecraft. Low-temperature plasmas could one day also make possible an entire new generation of miniature lasers and ultra-low-energy fluorescent light tubes. You can read more on this story here." And for some reason, the relatively low power requirements remind of me of the guts of the Improbability Drive.
First, protecting space vehicles from microdebris. This would be the single most useful space application of this technology for sattelites, shuttles, etc., as dust particles tend to hurt metal a lot if they're travelling at relative speeds of thousands of miles per hour. Since the terrestrial version of this thing has to be contained, however, I don't know if this is possible.
Second, fusion reaction containment. Since several plans for fusion technology seem to involve rather large heat generation, it'd be nice if this could be used to absorb the heat generated by the reaction and transmit it to generator equipment more safely (i.e. without frying the container). If the plasma is guided by magnetic fields (like so many things are), the extra energy should push the plasma bubble bigger, which can be used to induce currents directly. I'm guessing that this isn't a new idea, but I still think it's worth mentioning, especially since this would theoretically be one of the more efficient fusion->electricity conversions.
Either of these would be a huge advance (along with the rest of the stuff mentioned), so this is an impressive development indeed!
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Excuse me, but to my understanding the ordinary neon fluorescent lamps also contain "plasma" (when they are lit), caused by "electric current vis specially calibrated electrodes"....
The article has a rather high hype-to-explanation ratio... so I went looking for the patent they mention. Not so technical as to be incomprehensible, and more useful than the article, IMO. My first impression is that the advance here is the impedance matching system used to maintain the plasma, which allows the compact equipment and low power requirements. (I suppose it searches for the natural resonance of whatever ions you have between the electrodes... just find the lowest-energy state/standing wave at which it remains permittive/permeable.) And if you have low power plus no sealed chamber (1 atm, random molecular gases allowed), it pretty much follows that the result is a low temperature plasma, since plasma tends to radiate continuously. The scalability aspect is nice too... good for more than a toy.
Either I'm misunderstanding something, or the sterilization is done by the radiation from the plasma... basically just using the plasma as an efficient UV lamp. (The sterilization patent talks about sterilizing liquids or gels up to 2cm deep... I can't see doing that with the surface interactions, which might be sufficient for polished tools and the like.) This doesn't appear to be sufficient for a low-volume irradiation system for food, which is unfortunate, because I like my hamburgers juicy. Oh well. (Of course, prions survive irradiation anyway, so I would still have to worry about BSE.)
There is also a separate patent for "surface shielding". Might be fun to set up on your car :) I'm having trouble figuring out how the leakage from this system would be less detectable than the reflected radio waves it would disperse, though... I suppose if you do it right, all the radiation is absorbed by the gases you are ionizing?
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