Improving fast-ion confinement in high-performance discharges by suppressing Alfvén eigenmodes

Kramer, Geritt J.; Podestà, Mario; Holcomb, Christopher; Cui, L.; Gorelenkov, Nikolai N.; Grierson, Brian; Heidbrink, William W.; Nazikian, Raffi. M.; Solomon, Wayne M.; Van Zeeland, Michael A.; Zhu, Yubao

doi:10.1088/1741-4326/aa6456

Title: Improving fast-ion confinement in high-performance discharges by suppressing Alfvén eigenmodes

Journal Article · 28 March 2017 · Nuclear Fusion

DOI: https://doi.org/10.1088/1741-4326/aa6456 · OSTI ID:1353401

^[1];

^[1]; Holcomb, Christopher ^[2];

^[1]; Gorelenkov, Nikolai N. ^[1];

^[1]; Heidbrink, William W. ^[3]; Nazikian, Raffi. M. ^[1]; Solomon, Wayne M. ^[4]; Van Zeeland, Michael A. ^[4]; Zhu, Yubao ^[3]

Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Univ. of California, Irvine, CA (United States)
General Atomics, San Diego, CA (United States)

Here, we show that the degradation of fast-ion confinement in steady-state DIII-D discharges is quantitatively consistent with predictions based on the effects of multiple unstable Alfven eigenmodes on beam-ion transport. Simulation and experiment show that increasing the radius where the magnetic safety factor has its minimum is effective in minimizing beam-ion transport. This is favorable for achieving high performance steady-state operation in DIII-D and future reactors. A comparison between the experiments and a critical gradient model, in which only equilibrium profiles were used to predict the most unstable modes, show that in a number of cases this model reproduces the measured neutron rate well.

View Accepted Manuscript (DOE)

Cite

Export

Save

Research Organization:: Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States)

Sponsoring Organization:: USDOE Office of Science (SC), Fusion Energy Sciences (FES) (SC-24)

Grant/Contract Number:: AC02-09CH11466; FC02-04ER54698; AC52-07NA27344

OSTI ID:: 1353401

Journal Information:: Nuclear Fusion, Journal Name: Nuclear Fusion Journal Issue: 5 Vol. 57; ISSN 0029-5515

Publisher:: IOP ScienceCopyright Statement

Country of Publication:: United States

Language:: English

References (32)

NOVA: A nonvariational code for solving the MHD stability of axisymmetric toroidal plasmas Cheng, C. Z.; Chance, M. S. Journal of Computational Physics, Vol. 71, Issue 1 https://doi.org/10.1016/0021-9991(87)90023-4	journal	July 1987
Kinetic extensions of magnetohydrodynamics for axisymmetric toroidal plasmas Cheng, C. Z. Physics Reports, Vol. 211, Issue 1 https://doi.org/10.1016/0370-1573(92)90166-W	journal	February 1992
The tokamak Monte Carlo fast ion module NUBEAM in the National Transport Code Collaboration library Pankin, Alexei; McCune, Douglas; Andre, Robert Computer Physics Communications, Vol. 159, Issue 3 https://doi.org/10.1016/j.cpc.2003.11.002	journal	June 2004
Trapped electron stabilization of ballooning modes in low aspect ratio toroidal plasmas Cheng, C. Z.; Gorelenkov, N. N. Physics of Plasmas, Vol. 11, Issue 10 https://doi.org/10.1063/1.1783313	journal	October 2004
Plasma pressure effect on Alfvén cascade eigenmodes Breizman, B. N.; Pekker, M. S.; Sharapov, S. E. Physics of Plasmas, Vol. 12, Issue 11 https://doi.org/10.1063/1.2130692	journal	November 2005
Effects of pressure gradient on existence of Alfvén cascade modes in reversed shear tokamak plasmas Fu, G. Y.; Berk, H. L. Physics of Plasmas, Vol. 13, Issue 5 https://doi.org/10.1063/1.2196246	journal	May 2006
Measurements and modeling of Alfvén eigenmode induced fast ion transport and loss in DIII-D and ASDEX Upgrade Van Zeeland, M. A.; Heidbrink, W. W.; Fisher, R. K. Physics of Plasmas, Vol. 18, Issue 5 https://doi.org/10.1063/1.3574663	journal	May 2011
Plasma flow structures as analytical solution of a magneto-hydro-dynamic model with pressure Paccagnella, R. Physics of Plasmas, Vol. 19, Issue 3 https://doi.org/10.1063/1.3694048	journal	March 2012
1.5D quasilinear model and its application on beams interacting with Alfvén eigenmodes in DIII-D Ghantous, K.; Gorelenkov, N. N.; Berk, H. L. Physics of Plasmas, Vol. 19, Issue 9 https://doi.org/10.1063/1.4752011	journal	September 2012
Fast-ion transport in qmin>2, high- β steady-state scenarios on DIII-Da) Holcomb, C. T.; Heidbrink, W. W.; Ferron, J. R. Physics of Plasmas, Vol. 22, Issue 5 https://doi.org/10.1063/1.4921152	journal	May 2015
Fast-ion transport by Alfvén eigenmodes above a critical gradient threshold Heidbrink, W. W.; Collins, C. S.; Podestà, M. Physics of Plasmas, Vol. 24, Issue 5 https://doi.org/10.1063/1.4977535	journal	May 2017
Hamiltonian guiding center drift orbit calculation for plasmas of arbitrary cross section White, R. B.; Chance, M. S. Physics of Fluids, Vol. 27, Issue 10 https://doi.org/10.1063/1.864527	journal	January 1984
Existence of core localized toroidicity‐induced Alfvén eigenmode Fu, G. Y. Physics of Plasmas, Vol. 2, Issue 4 https://doi.org/10.1063/1.871382	journal	April 1995
Analysis of alpha particle‐driven toroidal Alfvén eigenmodes in Tokamak Fusion Test Reactor deuterium–tritium experiments Fu, G. Y.; Cheng, C. Z.; Budny, R. Physics of Plasmas, Vol. 3, Issue 11 https://doi.org/10.1063/1.871537	journal	November 1996
HINST : A two-dimensional code for high-n toroidicity induced Alfvén eigenmodes stability Gorelenkov, N. N.; Cheng, C. Z.; Tang, W. M. Physics of Plasmas, Vol. 5, Issue 9 https://doi.org/10.1063/1.873052	journal	September 1998
Simulations of alpha parameters in a TFTR DT supershot with high fusion power Budny, R. V.; Bell, M. G.; Janos, A. C. Nuclear Fusion, Vol. 35, Issue 12 https://doi.org/10.1088/0029-5515/35/12/I10	journal	December 1995
Magnetic safety factor profile before and after sawtooth crashes investigated with toroidicity and ellipticity induced Alfvén eigenmodes Kramer, G. J.; Cheng, C. Z.; Kusama, Y. Nuclear Fusion, Vol. 41, Issue 9 https://doi.org/10.1088/0029-5515/41/9/302	journal	September 2001
Simulations of beam ion transport during tearing modes in the DIII-D tokamak Carolipio, E. M.; Heidbrink, W. W.; Forest, C. B. Nuclear Fusion, Vol. 42, Issue 7 https://doi.org/10.1088/0029-5515/42/7/308	journal	July 2002
Beam anisotropy effect on Alfvén eigenmode stability in ITER-like plasmas Gorelenkov, N. N.; Berk, H. L.; Budny, R. V. Nuclear Fusion, Vol. 45, Issue 4 https://doi.org/10.1088/0029-5515/45/4/002	journal	March 2005
The effect of the fast-ion profile on Alfvén eigenmode stability Heidbrink, W. W.; Van Zeeland, M. A.; Austin, M. E. Nuclear Fusion, Vol. 53, Issue 9 https://doi.org/10.1088/0029-5515/53/9/093006	journal	August 2013
Development and validation of a critical gradient energetic particle driven Alfven eigenmode transport model for DIII-D tilted neutral beam experiments Waltz, R. E.; Bass, E. M.; Heidbrink, W. W. Nuclear Fusion, Vol. 55, Issue 12 https://doi.org/10.1088/0029-5515/55/12/123012	journal	October 2015
Synergy between fast-ion transport by core MHD and test blanket module fields in DIII-D experiments Heidbrink, W. W.; Austin, M. E.; Collins, C. S. Nuclear Fusion, Vol. 55, Issue 8 https://doi.org/10.1088/0029-5515/55/8/083023	journal	July 2015
Electron cyclotron heating can drastically alter reversed shear Alfvén eigenmode activity in DIII-D through finite pressure effects Van Zeeland, M. A.; Heidbrink, W. W.; Sharapov, S. E. Nuclear Fusion, Vol. 56, Issue 11 https://doi.org/10.1088/0029-5515/56/11/112007	journal	July 2016
Fast ion profile stiffness due to the resonance overlap of multiple Alfvén eigenmodes Todo, Y.; Van Zeeland, M. A.; Heidbrink, W. W. Nuclear Fusion, Vol. 56, Issue 11 https://doi.org/10.1088/0029-5515/56/11/112008	journal	July 2016
Validating predictive models for fast ion profile relaxation in burning plasmas Gorelenkov, N. N.; Heidbrink, W. W.; Kramer, G. J. Nuclear Fusion, Vol. 56, Issue 11 https://doi.org/10.1088/0029-5515/56/11/112015	journal	July 2016
Reversed shear Alfvén eigenmodes associated with the ellipticity and triangularity Alfvén gaps Kramer, G. J.; Fu, G-Y Plasma Physics and Controlled Fusion, Vol. 48, Issue 9 https://doi.org/10.1088/0741-3335/48/9/002	journal	July 2006
Reversed shear Alfvén eigenmodes in the frequency range of the triangularity induced gap on JET Kramer, G. J.; Fu, G. Y.; Nazikian, R. Plasma Physics and Controlled Fusion, Vol. 50, Issue 8 https://doi.org/10.1088/0741-3335/50/8/082001	journal	June 2008
A reduced fast ion transport model for the tokamak transport code TRANSP Podestà, M.; Gorelenkova, M.; White, R. B. Plasma Physics and Controlled Fusion, Vol. 56, Issue 5 https://doi.org/10.1088/0741-3335/56/5/055003	journal	April 2014
Confinement degradation by Alfvén-eigenmode induced fast-ion transport in steady-state scenario discharges Heidbrink, W. W.; Ferron, J. R.; Holcomb, C. T. Plasma Physics and Controlled Fusion, Vol. 56, Issue 9 https://doi.org/10.1088/0741-3335/56/9/095030	journal	August 2014
Observation of Critical-Gradient Behavior in Alfvén-Eigenmode-Induced Fast-Ion Transport Collins, C. S.; Heidbrink, W. W.; Austin, M. E. Physical Review Letters, Vol. 116, Issue 9 https://doi.org/10.1103/PhysRevLett.116.095001	journal	February 2016
Theoretical Interpretation of Alfvén Cascades in Tokamaks with Nonmonotonic q Profiles Berk, H. L.; Borba, D. N.; Breizman, B. N. Physical Review Letters, Vol. 87, Issue 18 https://doi.org/10.1103/PhysRevLett.87.185002	journal	October 2001
Observation of Odd Toroidal Alfvén Eigenmodes Kramer, G. J.; Sharapov, S. E.; Nazikian, R. Physical Review Letters, Vol. 92, Issue 1 https://doi.org/10.1103/PhysRevLett.92.015001	journal	January 2004

Cited By (6)

Integrated modeling of high β _N steady state scenario on DIII-D Park, J. M.; Ferron, J. R.; Holcomb, C. T. Physics of Plasmas, Vol. 25, Issue 1 https://doi.org/10.1063/1.5013021	journal	January 2018
Distortion of fuel-ion distribution functions by Alfvén eigenmodes in a tokamak DT plasma Sugiyama, S.; Matsuura, H.; Ogawa, K. Plasma Physics and Controlled Fusion, Vol. 60, Issue 10 https://doi.org/10.1088/1361-6587/aad76d	journal	August 2018
Subdominant modes and optimization trends of DIII-D reverse magnetic shear configurations Varela, J.; Spong, D. A.; Murakami, M. Nuclear Fusion, Vol. 59, Issue 4 https://doi.org/10.1088/1741-4326/ab0052	journal	February 2019
Alfvén eigenmodes and fast ion transport in negative triangularity DIII-D plasmas Van Zeeland, M. A.; Collins, C. S.; Heidbrink, W. W. Nuclear Fusion, Vol. 59, Issue 8 https://doi.org/10.1088/1741-4326/ab2488	journal	June 2019
Enhanced radial energy transport induced by radially curved Alfvén eigenmode wavefronts Kramer, G. J.; Tobias, B. J.; Turnbull, A. Nuclear Fusion, Vol. 59, Issue 9 https://doi.org/10.1088/1741-4326/ab2ee3	journal	July 2019
Subdominant modes and optimization trends of DIII-D reverse magnetic shear configurations Varela, J.; Spong, D. A.; Murakami, M. arXiv https://doi.org/10.48550/arxiv.1904.01193	text	January 2019

Similar Records

Confinement degradation by Alfvén-eigenmode induced fast-ion transport in steady-state scenario discharges

Journal Article · 2014 · Plasma Physics and Controlled Fusion · OSTI ID:1356336

Heidbrink, William W.; Ferron, John R.; Holcomb, Christopher T.; +9 more

Isotope impact on Alfvén eigenmodes and fast ion transport in DIII-D

Journal Article · 2024 · Nuclear Fusion · OSTI ID:2335945

Van Zeeland, M. A.; Bass, E.; Du, X. D.; +10 more

Alfven eigenmode stability and fast ion loss in DIII-D and ITER reversed magnetic shear plasmas

Conference · 2011 · OSTI ID:1055195

Van Zeeland, Michael; Gorelenkov, Nikolai; Heidbrink, W.; +12 more

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
Alfven eigenmodes
code
existence
fast-ion transport
high-performance plasmas
modes
simulations
stability
tokamak
toroidal plasmas
transport

Title: Improving fast-ion confinement in high-performance discharges by suppressing Alfvén eigenmodes

Citation Formats

References (32)

Cited By (6)

Similar Records

Related Subjects