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Fusion Propulsion Concept

  1. Jun 1, 2009 #1
    I came up with this during idle afternoon. Don't know if it's worth something but I wanted to discuss it with someone. Basically, outline of business part is given on the picture


    Horizontal tori are basically tokamaks and vertical pipes are "fusion combustion chambers" where working fluid is heated and ionized by fusion then directed downward to nozzles. Inner and outer tokamaks create magnetic field directed along vertical pipes , let's call it [tex]\vec{B}_v[/tex], and vertical pipes generate magnetic field approximately tangential to tokamaks, let's call this one [tex]\vec{B}_t[/tex]. Purpose of [tex]\vec{B}_v[/tex] is plasma confinement in tokamaks while purpose of [tex]\vec{B}_t[/tex] is plasma confinement in vertical pipes.

    Now, [tex]\vec{B}_t[/tex] is not perfectly tangential to tokamaks. Rather it's direction deviates from tangent for some angle [tex]\Delta\alpha[/tex] and it's intensity varies from average value on a torus by [tex]\Delta B_t[/tex]. Both [tex]\Delta\alpha[/tex] and[tex]\Delta B_t[/tex] are periodic functions along tokamak length. By increasing number of vertical pipes both [tex]\Delta\alpha[/tex] and [tex]\Delta B_t[/tex] get smaller, while they get bigger when distance between tori and pipes is decreased. As for intensity of vertical field along pipes, [tex]B_v[/tex] it also has periodic deviations.

    One advantage of setup like this (if it could work) is that it doesn't require separate magnets for confinement in tokamaks because tangential field is provided by ionized working fluid rushing out. We only have to provide magnets that create poloidal fields. This also makes tokamaks more energy efficient.

    Now, question is whether these deviations could be reduced enough by using appropriate number of toruses and pipes at appropriate distance, so that instabilities doesn't destroy confinement and fusion.

    Attached Files:

  2. jcsd
  3. Jun 1, 2009 #2
    Actually, I just had another idea.

    The fact that direction of magnetic field produced by vertical pipes deviates from tangential direction, and the fact that deviations are periodical along the length of the tokamaks might stabilize tokamak plasma in vertical direction because particle trajectories in tokamak will wiggle around in normal direction which will in combination with field produced by tokamaks provide force in vertical direction whose direction will change periodically along tokamak.
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