Plasma and antenna coupling characterization in ICRF-wall conditioning experiments

Ion Cyclotron Wall Conditioning (ICWC) discharges, in pulsed-mode operation, were carried out in the divertor tokamaks ASDEX Upgrade (AUG) and JET to simulate the scenario of ITER wall conditioning at half-field (AUG) and full-field (JET). ICWC-plasma and antenna coupling characterization results ob...

Full description

Saved in:
Bibliographic Details
Published in:Fusion engineering and design 2012-02, Vol.87 (2), p.98-103
Main Authors: Paul, Manash Kumar, Lyssoivan, A., Koch, R., Wauters, T., Douai, D., Bobkov, V., Van Eester, D., Lerche, E., Ongena, J., Rohde, V., Noterdaeme, J.-M., Graham, M., Mayoral, M.-L., Monakhov, I., Nightingale, M., Plyusnin, V.V.
Format: Article
Language:English
Subjects:
Antenna coupling
Antennas
Conditioning
Cyclotron frequency
ICRF discharge
Ion cyclotron radiation
ITER
Joining
Magnetic fields
Tokamaks
Wall conditioning
Walls
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Ion Cyclotron Wall Conditioning (ICWC) discharges, in pulsed-mode operation, were carried out in the divertor tokamaks ASDEX Upgrade (AUG) and JET to simulate the scenario of ITER wall conditioning at half-field (AUG) and full-field (JET). ICWC-plasma and antenna coupling characterization results obtained during the Ion Cyclotron Resonance Frequency (ICRF)-Wall Conditioning experiments performed in helium-hydrogen mixture in AUG and helium-deuterium mixtures in JET are presented here. Safe operational regimes for optimum ICWC in ITER could be explored for different magnetic fields. Satisfactory antenna coupling in the Mode Conversion scenario along with reproducible generation of ICRF plasmas and reliable wall conditioning were achieved by coupling RF power from one or two ICRF antennas at two (AUG, JET) different resonant frequencies. These results are in qualitative agreement with the predictions of 1-D TOMCAT code. Present study of ICWC indicates towards the beneficial effect of application of an additional (along with toroidal magnetic field) stationary vertical (BV≪BT) magnetic field on antenna coupling and plasma parameters. The results obtained from JET and AUG tokamaks, presented in this paper, emphasizes the proposed phenomenological schemes for further development of ICWC in superconducting tokamaks.
ISSN:0920-3796
1873-7196
DOI:10.1016/j.fusengdes.2011.10.009