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Cheating nature out of Fusion

  1. May 20, 2003 #1
    Can we consruct a centrifuge to accelerate ions and coerce them to fuse into heavier elements? It would have to be a sweeping electric field, because any moving parts would disintegrate from the great velocity they'd invariably have to have. Think fusion could be achieved this way?
     
  2. jcsd
  3. May 21, 2003 #2
    Intriguing idea. It would be one hell of an engineering challenge and it would be interesting to see if it took us a lot more energy to just get that electric field in the first place than to run the fusion reaction.
     
  4. May 21, 2003 #3
    Could be difficult. I suspect the energy required to do it that way would be huge. Nice idea though.
     
  5. May 22, 2003 #4
    spooky interesting...
     
  6. May 23, 2003 #5

    Integral

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    Isn't this essentially a partical accelerator as currently exists as places lile CERN and Fermi Labs? Ions are routinly accelerated to sigificant fractions of c and collided with similar beams rotatinging the opposite direction to create hi energy collisions between fundamental particals.

    Great Idea, but hardly original. :wink:
     
  7. May 26, 2003 #6
    Yes, except that I want to force the ions into the same place on the ring, instead of spread out evenly along the ring, the idea being that one could build up a significant number of ions together.
     
  8. May 26, 2003 #7
    I don't think great velocity need be primary so much as very precise velocity, I mean it may not be so much the speed of the collision as the exact trajectory like trying to land squarely on the top of a pyramid that is repulsive to anything moving toward it, unless it follows a perfectly straight flight path it will bounce off and slide down the side or in less it is moving at tremendous speeds in which the repulsive factor hasn't enough time to deflect the path, but if it lands exactly fusion might result. That's my crackpot analogy anyway, but doens't fusion always take energy and fission create it?
     
  9. May 27, 2003 #8

    drag

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    Greetings !

    There are many ideas that deal with accelerating
    hydrogen/its isotopes and squezing them together
    (a Tokomak essentially) and also ideas of smashing
    them together. But they are not suffciently effective.
    The distance required for fusing hydrogen is
    about 10^-15 m and that's very difficult to acvhieve.

    Live long and prosper.
     
  10. May 27, 2003 #9
    Sheesh, an atom is small enough that's about 100k times smaller.
    Maybe I should have said like trying to launch from space and land your skateboard on the tip of a repulsive pyramid.
     
    Last edited by a moderator: May 27, 2003
  11. May 27, 2003 #10
    all right then, I have a question for ya drag: why can't we accumulate enough ions in one place in a Tokamak to start sustainable reaction (or can we) ? The idea though is that instead of heating the fuel, you just accelerate it enough that the force from circular motion, (by default acceleration,) is greater than the coulomb repulive force etc.
     
  12. May 27, 2003 #11

    drag

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    Greetings !
    Pure numbers. I think your mathematical skills
    by far exceed mine schwarz so I'm sure you
    can easily do this and see the problem.
    (Basicly, if we need to overcome say a few KeV
    than we're talking about velocities equivalent
    to about 10^6 m/sec which is pretty high for
    protons and hydrogen isotopes.)

    Circuilar accelerators are used because you can
    accelerate the particles and then maintain the
    velocity with relativly little more energy input
    over a fairly long time period, thus increasing
    the likeliness of the reaction and the total
    energy output to input ratio.

    There are basicly 3 ways (as you may know) to
    contain a sustained fusion reaction:
    1. Gravitational.
    2. Electromagnetic.
    3. Enertial.

    Of course, in this case we are not talking about
    a direct self-sustaining reaction. However, the
    same methods are also required to enitiate it.

    BTW, an intresting thing that Warren(chroot), I
    believe, said in a different thread - quantum
    tunneling plays a significant part in a star's
    fusion proccess. Thus, had there been no quantum
    tunnelling the star would have to be more massive
    to enitiate and contain the reaction. (I have not
    confirmed this personally and he did not answer
    my question back then so I can't say how much
    is "significant".)

    So, theoreticly, if we could increase the chances
    of the relevant particles to tunnel and fuse
    we could increase the output this way too. But,
    if I'm not mistaken there is currently no way to
    do this and QM does not allow this.

    Live long and prosper.
     
  13. May 28, 2003 #12
    cool. that's interesting.
     
  14. May 28, 2003 #13
    I think it's cheaper just heating up the gas with lasers. The ol'fashion way :)
     
  15. Jun 1, 2003 #14

    drag

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    Either way you need the very strong EM fields to
    maintain the plasma and thus sustain the reaction.

    Live long and prosper.
     
  16. Jun 2, 2003 #15
    Don't forget that in a circular accelerator, synchrotron radiation tends lessen the energy of a particle beam. That's why circular accelerators (like the tevatron) have such a wide diameter. But maybe you could use this radiation to exite incoming ions in a centrifuge chamber? Kind of like pre-heating if that's possible. In either case drag is right; it's pure numbers. More energy in than out I assume.
     
  17. Jun 3, 2003 #16

    drag

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    I think AH meant heating without the use
    of an accelerator but by simply containing the
    plasma and using laser beams. Synchrotron or
    Bremstahlung radiation energy losses are probably
    not very significant in such a case.

    Live long and prosper.
     
  18. Jun 3, 2003 #17
    Looks like a misunderstanding. I wasn't replying to AH's post although it does look that way. And you're right. I noticed that synchrotron raditation output in Watts as pretty small. My bad.
     
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