skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: The role of RF in the optimized shear scenario on JET

Abstract

RF heating and current drive with ion cyclotron waves and Lower Hybrid waves have been crucial for the development of the Optimized Shear scenario on JET to high performance. Peaked electron temperature profiles and improved energy confinement could be obtained with electron heating both from LHCD and ICRH during plasma current ramp up. ICRH and NBI comparisons allow to separate heating and fueling and suggest a dominant role of core heating in the formation of an Internal Transport Barrier (ITB). ICRH and NBI powers are there equivalent. Pressure profile control by varying the composition of centrally peaked ICRF and broader NBI deposition improves MHD stability. Current profile modifications in a wide range have been obtained with LHCD and in combination with NBI during current ramp up. During the high performance phase, however, LH coupling degrades strongly due to the steep edge density gradient resulting in a drop of the density in front of the LH antenna to the cut-off density. High fusion performance achieving simultaneously high beta values and bootstrap currents is predicted in scenario modeling using pressure and current profile control with ICRF and LHCD.

Authors:
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;  [1]
  1. JET Joint Undertaking, Abingdon, Oxon, OX14 3EA (United Kingdom) (and others)
Publication Date:
OSTI Identifier:
21210467
Resource Type:
Journal Article
Journal Name:
AIP Conference Proceedings
Additional Journal Information:
Journal Volume: 485; Journal Issue: 1; Conference: 13. topical conference on radio frequency power in plasmas, Annapolis, MD (United States), 12-14 Apr 1999; Other Information: DOI: 10.1063/1.59749; (c) 1999 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0094-243X
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ANTENNAS; BOOTSTRAP CURRENT; CHARGED-PARTICLE TRANSPORT; COMPARATIVE EVALUATIONS; COUPLING; ELECTRON TEMPERATURE; ELECTRONS; HIGH-BETA PLASMA; ICR HEATING; ION PLASMA WAVES; ION TEMPERATURE; LOWER HYBRID CURRENT DRIVE; LOWER HYBRID HEATING; MAGNETOHYDRODYNAMICS; PLASMA INSTABILITY; PLASMA PRESSURE; RF SYSTEMS; SHEAR; THERMAL BARRIERS

Citation Formats

Soeldner, F. X., Alper, B., Baranov, Yu. F., Bickley, A., Challis, C. D., Conway, G., Cottrell, G. A., Benedetti, M. de, Deliyanakis, N., Erents, K., Gormezano, C., Gowers, C., Jones, T. T. C., Lomas, P. J., Maas, A., Mailloux, J., Parail, V. V., Rimini, F., Sips, A. C. C., and Smeulders, P. The role of RF in the optimized shear scenario on JET. United States: N. p., 1999. Web. doi:10.1063/1.59749.
Soeldner, F. X., Alper, B., Baranov, Yu. F., Bickley, A., Challis, C. D., Conway, G., Cottrell, G. A., Benedetti, M. de, Deliyanakis, N., Erents, K., Gormezano, C., Gowers, C., Jones, T. T. C., Lomas, P. J., Maas, A., Mailloux, J., Parail, V. V., Rimini, F., Sips, A. C. C., & Smeulders, P. The role of RF in the optimized shear scenario on JET. United States. doi:10.1063/1.59749.
Soeldner, F. X., Alper, B., Baranov, Yu. F., Bickley, A., Challis, C. D., Conway, G., Cottrell, G. A., Benedetti, M. de, Deliyanakis, N., Erents, K., Gormezano, C., Gowers, C., Jones, T. T. C., Lomas, P. J., Maas, A., Mailloux, J., Parail, V. V., Rimini, F., Sips, A. C. C., and Smeulders, P. Mon . "The role of RF in the optimized shear scenario on JET". United States. doi:10.1063/1.59749.
@article{osti_21210467,
title = {The role of RF in the optimized shear scenario on JET},
author = {Soeldner, F. X. and Alper, B. and Baranov, Yu. F. and Bickley, A. and Challis, C. D. and Conway, G. and Cottrell, G. A. and Benedetti, M. de and Deliyanakis, N. and Erents, K. and Gormezano, C. and Gowers, C. and Jones, T. T. C. and Lomas, P. J. and Maas, A. and Mailloux, J. and Parail, V. V. and Rimini, F. and Sips, A. C. C. and Smeulders, P.},
abstractNote = {RF heating and current drive with ion cyclotron waves and Lower Hybrid waves have been crucial for the development of the Optimized Shear scenario on JET to high performance. Peaked electron temperature profiles and improved energy confinement could be obtained with electron heating both from LHCD and ICRH during plasma current ramp up. ICRH and NBI comparisons allow to separate heating and fueling and suggest a dominant role of core heating in the formation of an Internal Transport Barrier (ITB). ICRH and NBI powers are there equivalent. Pressure profile control by varying the composition of centrally peaked ICRF and broader NBI deposition improves MHD stability. Current profile modifications in a wide range have been obtained with LHCD and in combination with NBI during current ramp up. During the high performance phase, however, LH coupling degrades strongly due to the steep edge density gradient resulting in a drop of the density in front of the LH antenna to the cut-off density. High fusion performance achieving simultaneously high beta values and bootstrap currents is predicted in scenario modeling using pressure and current profile control with ICRF and LHCD.},
doi = {10.1063/1.59749},
journal = {AIP Conference Proceedings},
issn = {0094-243X},
number = 1,
volume = 485,
place = {United States},
year = {1999},
month = {9}
}