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Fusion Power

  1. May 19, 2009 #1
    I have been researching about fusion power to understand how it operates during thermonuclear reactions. I do not understand how and how much deuterium and tritium are placed into the magnetic confinement (tokomak). I appreciate it, if anyone guides me about this.

    Thank you
  2. jcsd
  3. May 19, 2009 #2


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    The deuterium and tritium are ionized to form a plasma, and the plasma (ions and electrons) are confined by the magnetic field. The plasma excludes the magnetic field, and the ions and electrons rotate or more accurately, spiral along the magnetic field lines. The stronger the magnetic field (greater line density), the small the gyroradius of the ions and electrons. Within the plasma, where the magnetic field is low or virtually non-existent, the ions and electrons would have very large gyroradii, but they also scatter off each other.

    Basically in a torus, one starts with a neutral gas which is heated rapidly with a toroidal current (ohmic heating). That current is also subjected to an azimuthal magnetic field (caused by the toroidal current) which pushes inward on the current and then plasma, which forms as the neutral gas is heated by the current. Toroidal and poloidal magnetic fields are also applied for additional confinement and stability.
  4. May 19, 2009 #3
    Additional fuel is proposed to be added in a reactor set up with fuel pellet injection. Frozen deuterium and tritium in small pellets are shot into the plasma through the magnetic field. Compared to what you experience daily, a plasma is not that dense, so there's actually much less fuel than what I expected. Exactly how much depends on the volume of confinement.
  5. May 20, 2009 #4
    Hi there,

    In the idea of fusion power, the amount of combustible needed will depend mainly on your expected output power. If you want to have a small experimental fusion plant compared to a few 1000MWe, will vary the amount of fuel needed.

  6. May 22, 2009 #5
    Now, I am a little confused. Is it sent into the tokomak in the form or gas or injected as frozen pellets. Maybe, It starts with neutral gas and later fed with D-T ice pellets???
  7. May 24, 2009 #6
    Thanks. Your answers made it clear. I also got some anwsers in this website..

    http://www.fusion.org.uk/info/glossary/glossmain.htm [Broken]
    Last edited by a moderator: May 4, 2017
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