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THERMOELECTRIC ROTATING TORUS FOR FUSION
| Author: | Hassam A. B. |
| Coauthor: | Yi-Min Huang |
| Institution : | Univ of Maryland |
| Abstract text: |
A concept for fusion that combines plasma thermoelectricity with sheared flow stabilization is proposed. This device may have no practical limit on plasma density and may require only relatively weak external magnetic field coils to construct. In magnetized plasma, thermoelectric currents can be driven across the magnetic field if an electron temperature gradient is maintained across the field. Theoretical studies show that external heating power that maintains a hot central temperature can concomitantly maintain an encircling magnetic field against resistive diffusion. The magnetic field can, in fact, be built up from a weak, seed field to a steady state value, characterized by the magnetic energy density being of order the thermal energy. A toroidal chamber with a weak seed toroidal current is needed to start this off. The plasma is now heated. As the pressure increases, thermolelectric currents build up a poloidal magnetic field to just the right amount needed to maintain pressure balance and equilibrium, with the only caveat that the density adjusts itself such that n ~ T-1/4. It is well known that the plasma configuration described above is unstable to MHD kink modes and sausage modes. To suppress these, the plasma is to be forced to rotate toroidally. Input power is needed to maintain the plasma toroidal momentum. The momentum losses are dissipated as heat; this same power can then be shown to be sufficient to heat the plasma. Drawbacks to this system are a large aspect ratio (~ 20) and recirculating power needed to maintain the rotation. However, the advantages are novel and compelling - no large electromagnets are required (no TF, only weak seed PF and VF), and there is no limit on pressure (pressure is not limited by tech limits on external magnetic fields since the field is almost all self-generated).
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