Session KP01 - Poster Session III.
POSTER session, Tuesday afternoon, March 23
Exhibit Hall, GWCC
The levitated dipole configuration offers the possibility of confining a high beta plasma in a configuration which is steady-state and disruption free. The concept may permit the outward convection of ash and provides a natural low-power-density divertor. Additionally, we have shown that drift frequency fluctuations will be stable(Kesner, Phys Plasmas 4) (1997) 419; 5 (1998) 3675. so that we might expect near-classical confinement. The requirement of a superconducting ring internal to the plasma makes this approach compatible with an advanced fuel (i.e. D-^3He) fusion cycle.
We are in the process of constructing a small levitated dipole experiment, LDX as a joint project between MIT and Columbia University. The experiment will utilize a superconducting ring of approximately 0.8 m diameter and levitated within a 2.5 m radius vacuum chamber. MHD theory predicts that the peak pressure is related to the edge pressure by the flux expansion, i.e. p_max/p_edge =(V_edge/V_max)^\gamma with V=øint dl/B and \gamma=5/3 and we have designed LDX to obtain p_max/p_edge>10^4. We will also discuss schemes to further enhance the plasma pressure including H-mode-type pedestals and scrape-off-layer heating.