Energy Confinement Predictions for the Stabilized Tandem Mirror and GAMMA-10
Author: Wendell Horton
Requested Type: Consider for Invited
Submitted: 2006-12-07 11:51:09
Co-authors: J. Pratt, H.L. Berk
Contact Info:
University of Texas at Austin, IFS
1 University Station C1600
Austin,, TX 78712-0
USA
Abstract Text:
The absence of toroidal curvature and relatively weak
internal plasma parallel currents in a tandem mirror gives the system strongly favorable stability and transport properties. GAMMA-10 experiments (T. Cho it et al.rm~ PRL, 2006) demonstrate that sheared plasma rotation suppresses turbulent radial losses through control of the radial potential profiles. Recent achievements of the GAMMA-10 include 3 keV ion confinement potentials and $T_e geq 800 $ eV. Total energy confinement times for the GAMMA-10 experiment are significantly larger than corresponding empirical confinement times in toroidal devices. At the temperatures achieved in the GAMMA-10, the end loss rate $tau_{rm Past.} simeq 100$ ms so that radial losses determine $tau_E$, as intended in tandem mirror reactor designs (Post it et al.rm~ Fusion Science and Technology, 47,2005). Drift waves results on radial confinement times developed using Bohm, gyro-Bohm, and electron temperature gradient (ETG) scalings imply that the tandem mirror has a qualitatively different form of drift wave radial transport from that in toroidal devices (W. Horton it et al.rm~ Proceedings OS 2006 and J. Pratt and W. Horton. Phys. Plasmas, 13, 2006). We analyze electrostatic drift wave eigenmodes for the GAMMA-10 the electrostatic potential and the magnetic perturbation. We use tera-flop, large scale parallel computers to integrate the orbits in models of the drift wave losses in the GAMMA-10. We extrapolate the results to the kinetically stabilized tandem mirror reactor.
Work supported by the Department of Energy Grant DE-FG02-04ER5474.
Characterization: A2
Comments:
