Abstract
The configuration dependence of parallel momentum inputs to target plasma particle species by tangentially injected neutral beams is investigated in non-axisymmetric stellarator/heliotron model magnetic fields by assuming the existence of magnetic flux-surfaces. In parallel friction integrals of the full Rosenbluth-MacDonald-Judd collision operator in thermal particles' kinetic equations, numerically obtained eigenfunctions are used for excluding trapped fast ions that cannot contribute to the friction integrals. It is found that the momentum inputs to thermal ions strongly depend on magnetic field strength modulations on the flux-surfaces, while the input to electrons is insensitive to the modulation. In future plasma flow studies requiring flow calculations of all particle species in more general non-symmetric toroidal configurations, the eigenfunction method investigated here will be useful.
Highlights
Impurity flow velocities of NBI(neutral beam injection) heated plasmas in Heliotron-J were successfully explained by the neoclassical transport theory1,2
As pointed out in many experimental[12,13] and theoretical[34] studies on NBI heated plasmas, situations of recent experiments with the external anisotropic heating are different from those assumed in the conventional MHD equilibrium theories[16] and the concept of the flux-surface coordinates[11] based on them using the isotropic pressure
It is suggested for practical purposes that isotropic pressure equilibriums reproducing experimentally observed Shafranov shifts, in which the usual scalar pressure moment pa is replaced by (p∥a + p⊥a )/2, would give the parama a eters and the field strength in Eq(12)[13]
Summary
Impurity flow velocities of NBI(neutral beam injection) heated plasmas in Heliotron-J were successfully explained by the neoclassical transport theory. Because of an extreme difference between the velocity moments in the tangential NBI, we do not need to retain the Galilean invariant property so rigorously in this Cfb (ff , fb ) In this approximation, for retaining the conservation of momentum and energy, collisions of thermalized particles (a) with the fast ions (f) should be calculated by Caf (fa , ff ) ∼. This kind of perpendicular gradient effects b×∇f f of the fast ions at |v − vb | /vb ≪ 1 in NBI heated and/or burning plasmas cannot be investigated only by the drift approximation for describing the gyro-phase-averaged velocity distribution functions.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
