EFD-P(11)50
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Study of ICRH Scenarios for Thermal Ion Heating in JET DT Plasmas
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Ye.O. Kazakov, V.G. Kiptily, S.E. Sharapov, D. Van Eester
and JET EFDA contributors
Abstract.
Various Ion Cyclotron Resonance Heating (ICRH) scenarios relevant for D-T phase of the
JET tokamak are studied. Recent ICRH experiments in JET
(3He)-D and (3He)-H plasmas
confirmed the possibility of electron heating enhancement in the mode conversion regime due to
the constructive interference of the reflected fast waves. Such a heating enhancement in D-T
plasma is investigated first for JET-like conditions for both dipole and
+/2 ICRH antenna phasing, and for T concentration varied from 0 to
100%. It is shown that most of the mode conversion
scenarios at comparable concentrations of D and T species suffer from a parasitic absorption by
fusion-born alpha-particles and NBI-produced fast ions whereas
the impact of such fast ions in the minority heating ICRH schemes is substantially smaller. A possibility of
ion heating enhancement due to the interference effect is shown for the minority heating scenarios. It is found
that thermal ion heating becomes dominant in tritium-rich plasmas with T concentration ~80%. The
efficiency of ion heating in such a scenario is compared with the alternative
3He minority ICRH scenario in D:T = 50:50 plasmas.
Preprint of Paper to be submitted for publication in
Nuclear Fusion
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