| IT16 · Integrated Analysis of
Alfvén Eigenmode in Toroidal Plasmas A. Fukuyama and A. Sonoda
Department of Nuclear Engineering, Kyoto 606-8501, Japan
fukuyama@nucleng.kyoto-u.ac.jp
Abstract: The linear stability of
Alfvén eigenmodes (AE) is numerically studied for various configurations in
toroidal plasmas. We use the three-dimension full wave code (TASK/WM) which
solves Maxwell's equation with a kinetic dielectric tensor in a magnetic
flux coordinates as a boundary value problem and obtain the spatial
structure of an Alfvén eigenmode with a complex eigen frequency. The
TASK/WM code is now included as a module in the integrated simulation code
system, TASK. We may employ spatial profiles predicted by the transport
module or obtained from the ITPA profile database. We may also make use of
the velocity distribution function of energetic ions computed by the
three-dimensional bounce-averaged Fokker-Planck module. The distribution
function is numerically integrated to give the kinetic dielectric
tensor.
We consider three cases: (1) Q=10 standard operation on
ITER, (2) advanced operation with negative magnetic shear on ITER, (3)
helical configuration on compact helical system (CHS). In the case of ITER
standard operation, the profiles of density, temperature and safety factor
are computed by the transport module with the CDBM turbulent transport
model. The dependence of the AE stability on the energy distribution
function of alpha particles is examined by varying the external heating
profile. In the case of ITER advanced operation, systematic study on the
magnetic shear and the internal transport barrier of density is carried out.
In the case of CHS plasma, three-dimensional magnetic configuration
calculated by the MHD equilibrium code, VMEC, is employed. The linear
stabilities of global, toroidal and helical AEs are examined and the results
are compared with experimental observations.
Formulation for the integro-differential analysis
including the effects of finite particle orbit size will be also discussed.
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