Advanced Fuelling System for use as a Burn Control Tool in a Burning Plasma Device
Author: Roger Raman
Steady-state Advanced Tokamak (AT) scenarios rely on optimized density and pressure profiles to maximize the bootstrap current fraction. Under this mode of operation, the fuelling system must deposit small amounts of fuel where it is needed, and as often as needed, so as to compensate for fuel losses, but not to adversely alter the established density and pressure profiles. Conventional fuelling methods have not demonstrated successful fuelling of AT-type discharges and may be incapable of deep fuelling long pulse ELM-free discharges in ITER. The capability to deposit fuel at any desired radial location within the tokamak would provide burn control capability through alteration of the density profile. The ability to peak the density profile would ease ignition requirements, while operating ITER with density profiles that are peaked would increase the fusion power output. An advanced fuelling system should also be capable of fuelling well past internal transport barriers. Compact Toroid (CT) fuelling has the potential to meet these needs, while simultaneously providing a source of toroidal momentum input. Experimental data needed for the design of a CT fueller for ITER could be obtained on NSTX using an existing CT injector.
_____________________________________________________________________________
PPPL-4221 PREPRINT* (February 2007) (pdf 215 Kb)
*NOTICE: this is the author's version of a work that was accepted for publication in Fusion Science and Technology. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version will be published in:
Fusion Science and Technology