학술논문

Results of Predictive Fokker-Planck Modelling of NBI Deuterons in ITER
Document Type
Source
Journal of fusion energy. 30(4):307-322
Subject
Tokamak
Neutral beam injection
Beam angular divergence
Fokker-Planck equation
Current drive
NATURAL SCIENCES
NATURVETENSKAP
Language
English
ISSN
0164-0313
1572-9591
Abstract
First an analytical formalism is presented for calculating the source distribution of ions generated by neutral beam injection (NBI) in tokamak plasmas. A general NBI ion source term, applicable to studies in the phase space up to 6 dimensions, is provided for neutral beams with finite thickness and divergence. Further, using this source term for the envisaged NBI in ITER, we carry out 3D Fokker-Planck modelling of the steady-state deuteron distribution function of NBI produced fast deuterons relaxing on bulk plasma components. For two basic ITER scenarios we demonstrate the poloidal profiles of the beam deuteron density, of the NBI generated current as well as of the NBI power deposition to bulk electrons and ions. Further, we evaluate the capability of gamma and NPA diagnostics of NBI ions in ITER and demonstrate the sensitivity of the distributions of NBI generated ions to different ITER operation scenarios.