Impurity transport at the plasma edge : the transition from 2D to 1D models in axisymmetric toroidal systems and the role of poloidal source distributions
After consideration of anomalous transport phenomena resulting from electromagnetic field fluctuations, a 2-D drift-kinetic equation for impurity ions was formulated in toroidal coordinates assuming the usual model for the helical magnetic field in axisymmetric tokamak configurations. A general solution for T(parallel) not equal to T(perpendicular) (different kinetic temperatures for longitudinal and cross-field thermal motion) can be constructed in the form of a series expansion in Hermite polynomials with respect to v(parallel) and in Laguerre polynomials with respect to v(perpendicular), which in the limit T(parallel) = T(perpendicular) is equivalent to a gyro-averaged version of Grad's expansion in tensorial Hermite polynomials. This paper includes a discussion of the 2-D drift-kinetic equations for impurity ions in an axisymmetric plasma (pre-supposing a toroidally symmetric limiter), an outline of their solution by a specific moment approach and an illustration of the derivation of the 1-D model.
Bibliographic Reference: Report: Institut für Plasmaphysik Jül-2576 EN (1992) 39 pp.
Availability: Available from Forschungszentrum Jülich GmbH, Zentralbibliothek, Postfach 1913, D-5170 Jülich (DE)
Record Number: 199210850 / Last updated on: 1994-12-02
Original language: en
Available languages: en