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Brochard G, Liu C, Wei X, Heidbrink W, Lin Z, Gorelenkov N, Chrystal C, Du X, Bao J, Polevoi AR, Schneider M, Kim SH, Pinches SD, Liu P, Nicolau JH, Lütjens H. Saturation of Fishbone Instability by Self-Generated Zonal Flows in Tokamak Plasmas. Phys Rev Lett 2024; 132:075101. [PMID: 38427884 DOI: 10.1103/physrevlett.132.075101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 09/15/2023] [Accepted: 11/09/2023] [Indexed: 03/03/2024]
Abstract
Gyrokinetic simulations of the fishbone instability in DIII-D tokamak plasmas find that self-generated zonal flows can dominate the nonlinear saturation by preventing coherent structures from persisting or drifting in the energetic particle phase space when the mode frequency down-chirps. Results from the simulation with zonal flows agree quantitatively, for the first time, with experimental measurements of the fishbone saturation amplitude and energetic particle transport. Moreover, the fishbone-induced zonal flows are likely responsible for the formation of an internal transport barrier that was observed after fishbone bursts in this DIII-D experiment. Finally, gyrokinetic simulations of a related ITER baseline scenario show that the fishbone induces insignificant energetic particle redistribution and may enable high performance scenarios in ITER burning plasma experiments.
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Affiliation(s)
- G Brochard
- ITER organisation, Route de Vinon-sur-Verdon, CS 90 046 13067 St., Paul Lez Durance, France
- Department of Physics and Astronomy, University of California, Irvine, California 92697, USA
| | - C Liu
- Princeton Plasma Physics Laboratory, Princeton University, P.O. Box 451, Princeton, New Jersey 08543,USA
| | - X Wei
- Department of Physics and Astronomy, University of California, Irvine, California 92697, USA
| | - W Heidbrink
- Department of Physics and Astronomy, University of California, Irvine, California 92697, USA
| | - Z Lin
- Department of Physics and Astronomy, University of California, Irvine, California 92697, USA
| | - N Gorelenkov
- Princeton Plasma Physics Laboratory, Princeton University, P.O. Box 451, Princeton, New Jersey 08543,USA
| | - C Chrystal
- General Atomics, P.O. Box 85608, San Diego, California 92186-5608, USA
| | - X Du
- General Atomics, P.O. Box 85608, San Diego, California 92186-5608, USA
| | - J Bao
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - A R Polevoi
- ITER organisation, Route de Vinon-sur-Verdon, CS 90 046 13067 St., Paul Lez Durance, France
| | - M Schneider
- ITER organisation, Route de Vinon-sur-Verdon, CS 90 046 13067 St., Paul Lez Durance, France
| | - S H Kim
- ITER organisation, Route de Vinon-sur-Verdon, CS 90 046 13067 St., Paul Lez Durance, France
| | - S D Pinches
- ITER organisation, Route de Vinon-sur-Verdon, CS 90 046 13067 St., Paul Lez Durance, France
| | - P Liu
- Department of Physics and Astronomy, University of California, Irvine, California 92697, USA
| | - J H Nicolau
- Department of Physics and Astronomy, University of California, Irvine, California 92697, USA
| | - H Lütjens
- CPHT, CNRS, École Polytechnique, Institut Polytechnique de Paris, Route de Saclay, 91128 Palaiseau, France
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Liu P, Wei X, Lin Z, Brochard G, Choi GJ, Heidbrink WW, Nicolau JH, McKee GR. Regulation of Alfvén Eigenmodes by Microturbulence in Fusion Plasmas. Phys Rev Lett 2022; 128:185001. [PMID: 35594094 DOI: 10.1103/physrevlett.128.185001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Revised: 02/07/2022] [Accepted: 04/06/2022] [Indexed: 06/15/2023]
Abstract
Global gyrokinetic simulations of mesoscale reversed shear Alfven eigenmodes (RSAE) excited by energetic particles (EP) in fusion plasmas find that RSAE amplitude and EP transport are much higher than experimental levels at nonlinear saturation, but quickly diminish to very low levels after the saturation if background microturbulence is artificially suppressed. In contrast, in simulations coupling micro-meso scales, the RSAE amplitude and EP transport decrease drastically at the initial saturation but later increases to the experimental levels in the quasisteady state with bursty dynamics due to regulation by thermal ion temperature gradient (ITG) microturbulence. The quasisteady state EP transport is larger for a stronger microturbulence. The RSAE amplitude in the quasisteady state ITG-RSAE turbulence from gyrokinetic simulations, for the first time, agrees very well with experimental measurements.
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Affiliation(s)
- P Liu
- Department of Physics and Astronomy, University of California, Irvine, California 92697, USA
| | - X Wei
- Department of Physics and Astronomy, University of California, Irvine, California 92697, USA
| | - Z Lin
- Department of Physics and Astronomy, University of California, Irvine, California 92697, USA
| | - G Brochard
- Department of Physics and Astronomy, University of California, Irvine, California 92697, USA
| | - G J Choi
- Department of Physics and Astronomy, University of California, Irvine, California 92697, USA
| | - W W Heidbrink
- Department of Physics and Astronomy, University of California, Irvine, California 92697, USA
| | - J H Nicolau
- Department of Physics and Astronomy, University of California, Irvine, California 92697, USA
| | - G R McKee
- College of Engineering, University of Wisconsin, Madison, Wisconsin 53706, USA
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