Abstract Details
Abstracts
Author: Nikolai N. Gorelenkov
Requested Type: Poster
Submitted: 2019-02-18 11:06:51
Co-authors:
Contact Info:
PPPL, Princeton University
PO Box 451
Princeton, NJ 08502
USA
Abstract Text:
We are revisiting the instabilities of fishbone and ideal kink modes relying on the nonperturbative treatment of fast ion plasma specie [C.Z. Cheng, Phys.Reports v.211,p.1 (1992), N.N.Gorelenkov, IAEA TCM on alpha particles in fusion research, Austin 2011]. This is motivated by the selfconsistent treatment of the plasma equilibrium with the fast ion anisotropy and toroidal rotation [N.N.Gorelenkov, L.E.Zakharov, Nucl.Fusion v.58,p.082031 (2018)]. Global nonperturbative hybrid kinetic-MHD approach is formulated for NOVA-KN code. It finds the resonant (fishbone) and non-resonant (ideal) branches.
The nonperturbative approach treats fast ions with their realistic
drift orbits numerically by computing the moments of their distribution function in order to include them into the eigenmode equation. We employ this technique together with the conforming velocity space grid to evaluate the wave-particle interaction matrices. Both resonant (fishbones) and modified non-resonant (ideal) branches are studied to understand their stability properties in the presence of energetic ions.
The destabilizing effects from energetic beam ions and alpha particles on $m/n=1/1$ mode are important for studied instabilities and the following operational scenarious of the tokamaks. A model for beam ion distribution funciton is included. We study the properties of those branches in details in applications for burning plasmas. The results are discussed to understand how far the stability region of the operating space can be from the nominal
values of a fusion device like ITER.
Comments:
