Fast-ion physics in SPARC
Abstract
Potential loss of energetic ions including alphas and radio-frequency tail ions due to classical orbit effects and magnetohydrodynamic instabilities (MHD) are central physics issues in the design and experimental physics programme of the SPARC tokamak. The expected loss of fusion alpha power due to ripple-induced transport is computed for the SPARC tokamak design by the ASCOT and SPIRAL orbit-simulation codes, to assess the expected surface heating of plasma-facing components. We find good agreement between the ASCOT and SPIRAL simulation results not only in integrated quantities (fraction of alpha power loss) but also in the spatial, temporal and pitch-angle dependence of the losses. If the toroidal field (TF) coils are well-aligned, the SPARC edge ripple is small (0.15–0.30 %), the computed ripple-induced alpha power loss is small ( $${\sim } 0.25\,\%$$ ) and the corresponding peak surface power density is acceptable ( $$244\ \textrm{kW}\ \textrm {m}^{-2}$$ ). However, the ripple and ripple-induced losses increase strongly if the TF coils are assumed to suffer increasing magnitudes of misalignment. Surface heat loads may become problematic if the TF coil misalignment approaches the centimetre level. Ripple-induced losses of the energetic ion tail driven by ion cyclotron range of frequency (ICRF) heating are not expected to generate significant wall or limiter heating in the nominal SPARC plasma scenario. Because the expected classical fast-ion losses are small, SPARC will be able to observe and study fast-ion redistribution due to MHD including sawteeth and Alfvén eigenmodes (AEs). SPARC's parameter space for AE physics even at moderate $$Q$$ is shown to reasonably overlap that of the demonstration power plant ARC (Sorbom et al., Fusion Engng Des., vol. 100, 2015, p. 378), and thus measurements of AE mode amplitude, spectrum and associated fast-ion transport in SPARC would provide relevant guidance about AE behaviour expected in ARC.
- Authors:
-
- Commonwealth Fusion Systems, Cambridge, MA (United States)
- Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
- Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Plasma Science and Fusion Center
- Aalto Univ., Espoo (Finland)
- Chalmers Univ. of Technology, Gothenburg (Sweden)
- Publication Date:
- Research Org.:
- Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Commonwealth Fusion Systems, Cambridge, MA (United States)
- Sponsoring Org.:
- USDOE; Commonwealth Fusion Systems; National Science Foundation (NSF); Academy of Finland
- Contributing Org.:
- INFUSE programme; Commonwealth Fusion Systems, DOE INFUSE program, National Science Foundation Graduate Research Fellowship, National Energy Research Scientific Computing Center, Academy of Finland
- OSTI Identifier:
- 1668281
- Alternate Identifier(s):
- OSTI ID: 1774366
- Grant/Contract Number:
- AC02-05CH11231; RPP005; 1122374; 324759; AC02-09CH11466
- Resource Type:
- Accepted Manuscript
- Journal Name:
- Journal of Plasma Physics
- Additional Journal Information:
- Journal Volume: 86; Journal Issue: 5; Journal ID: ISSN 0022-3778
- Publisher:
- Cambridge University Press
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; fusion plasma; plasma simulation; plasma confinement
Citation Formats
Scott, S. D., Kramer, G. J., Tolman, E. A., Snicker, A., Varje, J., Särkimäki, K., Wright, J. C., and Rodriguez-Fernandez, P. Fast-ion physics in SPARC. United States: N. p., 2020.
Web. doi:10.1017/s0022377820001087.
Scott, S. D., Kramer, G. J., Tolman, E. A., Snicker, A., Varje, J., Särkimäki, K., Wright, J. C., & Rodriguez-Fernandez, P. Fast-ion physics in SPARC. United States. https://doi.org/10.1017/s0022377820001087
Scott, S. D., Kramer, G. J., Tolman, E. A., Snicker, A., Varje, J., Särkimäki, K., Wright, J. C., and Rodriguez-Fernandez, P. Tue .
"Fast-ion physics in SPARC". United States. https://doi.org/10.1017/s0022377820001087. https://www.osti.gov/servlets/purl/1668281.
@article{osti_1668281,
title = {Fast-ion physics in SPARC},
author = {Scott, S. D. and Kramer, G. J. and Tolman, E. A. and Snicker, A. and Varje, J. and Särkimäki, K. and Wright, J. C. and Rodriguez-Fernandez, P.},
abstractNote = {Potential loss of energetic ions including alphas and radio-frequency tail ions due to classical orbit effects and magnetohydrodynamic instabilities (MHD) are central physics issues in the design and experimental physics programme of the SPARC tokamak. The expected loss of fusion alpha power due to ripple-induced transport is computed for the SPARC tokamak design by the ASCOT and SPIRAL orbit-simulation codes, to assess the expected surface heating of plasma-facing components. We find good agreement between the ASCOT and SPIRAL simulation results not only in integrated quantities (fraction of alpha power loss) but also in the spatial, temporal and pitch-angle dependence of the losses. If the toroidal field (TF) coils are well-aligned, the SPARC edge ripple is small (0.15–0.30 %), the computed ripple-induced alpha power loss is small ( ${\sim } 0.25\,\%$ ) and the corresponding peak surface power density is acceptable ( $244\ \textrm{kW}\ \textrm {m}^{-2}$ ). However, the ripple and ripple-induced losses increase strongly if the TF coils are assumed to suffer increasing magnitudes of misalignment. Surface heat loads may become problematic if the TF coil misalignment approaches the centimetre level. Ripple-induced losses of the energetic ion tail driven by ion cyclotron range of frequency (ICRF) heating are not expected to generate significant wall or limiter heating in the nominal SPARC plasma scenario. Because the expected classical fast-ion losses are small, SPARC will be able to observe and study fast-ion redistribution due to MHD including sawteeth and Alfvén eigenmodes (AEs). SPARC's parameter space for AE physics even at moderate $Q$ is shown to reasonably overlap that of the demonstration power plant ARC (Sorbom et al., Fusion Engng Des., vol. 100, 2015, p. 378), and thus measurements of AE mode amplitude, spectrum and associated fast-ion transport in SPARC would provide relevant guidance about AE behaviour expected in ARC.},
doi = {10.1017/s0022377820001087},
journal = {Journal of Plasma Physics},
number = 5,
volume = 86,
place = {United States},
year = {Tue Sep 29 00:00:00 EDT 2020},
month = {Tue Sep 29 00:00:00 EDT 2020}
}
Figures / Tables:
Works referenced in this record:
A description of the full-particle-orbit-following SPIRAL code for simulating fast-ion experiments in tokamaks
journal, January 2013
- Kramer, G. J.; Budny, R. V.; Bortolon, A.
- Plasma Physics and Controlled Fusion, Vol. 55, Issue 2
Comparison of fusion alpha performance in JET advanced scenario and H-mode plasmas
journal, November 2008
- Asunta, O.; Kurki-Suonio, T.; Tala, T.
- Plasma Physics and Controlled Fusion, Vol. 50, Issue 12
The role of alpha particles in tokamak reactors
journal, June 1980
- Kolesnichenko, Ya. I.
- Nuclear Fusion, Vol. 20, Issue 6
Physics of Alfvén waves and energetic particles in burning plasmas
journal, March 2016
- Chen, Liu; Zonca, Fulvio
- Reviews of Modern Physics, Vol. 88, Issue 1
Observation of beta-induced Alfvén eigenmodes in the DIII-D tokamak
journal, August 1993
- Heidbrink, W. W.; Strait, E. J.; Chu, M. S.
- Physical Review Letters, Vol. 71, Issue 6
Mitigation of Alfvénic activity by 3D magnetic perturbations on NSTX
journal, July 2016
- Kramer, G. J.; Bortolon, A.; Ferraro, N. M.
- Plasma Physics and Controlled Fusion, Vol. 58, Issue 8
Excitation of high‐ n toroidicity‐induced shear Alfvén eigenmodes by energetic particles and fusion alpha particles in tokamaks
journal, November 1992
- Fu, G. Y.; Cheng, C. Z.
- Physics of Fluids B: Plasma Physics, Vol. 4, Issue 11
Hamiltonian guiding center drift orbit calculation for plasmas of arbitrary cross section
journal, January 1984
- White, R. B.; Chance, M. S.
- Physics of Fluids, Vol. 27, Issue 10
Interpretation of recent power width measurements in JET MkIIGB ELMy H-modes
journal, May 2002
- Fundamenski, W.; Sipilä, S.; Matthews, G. F.
- Plasma Physics and Controlled Fusion, Vol. 44, Issue 6
Toroidal Alfvén eigenmode‐induced ripple trapping
journal, August 1995
- White, R. B.; Fredrickson, E.; Darrow, D.
- Physics of Plasmas, Vol. 2, Issue 8
Excitation of the toroidicity‐induced shear Alfvén eigenmode by fusion alpha particles in an ignited tokamak
journal, October 1989
- Fu, G. Y.; Van Dam, J. W.
- Physics of Fluids B: Plasma Physics, Vol. 1, Issue 10
Study of stochastic toroidal field ripple losses of charged fusion products at the midplane of TFTR
journal, March 1993
- Boivin, R. L.; Zweben, S. J.; White, R. B.
- Nuclear Fusion, Vol. 33, Issue 3
Fast ion transport during applied 3D magnetic perturbations on DIII-D
journal, June 2015
- Van Zeeland, M. A.; Ferraro, N. M.; Grierson, B. A.
- Nuclear Fusion, Vol. 55, Issue 7
Neoclassical diffusion arising from magnetic-field ripples in Tokamaks
journal, March 1973
- Connor, J. W.; Hastie, R. J.
- Nuclear Fusion, Vol. 13, Issue 2
ARC: A compact, high-field, fusion nuclear science facility and demonstration power plant with demountable magnets
journal, November 2015
- Sorbom, B. N.; Ball, J.; Palmer, T. R.
- Fusion Engineering and Design, Vol. 100
Volume-preserving algorithm for secular relativistic dynamics of charged particles
journal, April 2015
- Zhang, Ruili; Liu, Jian; Qin, Hong
- Physics of Plasmas, Vol. 22, Issue 4
ASCOT simulations of fast ion power loads to the plasma-facing components in ITER
journal, August 2009
- Kurki-Suonio, T.; Asunta, O.; Hellsten, T.
- Nuclear Fusion, Vol. 49, Issue 9
Fast-ion effects during test blanket module simulation experiments in DIII-D
journal, September 2011
- Kramer, G. J.; Budny, B. V.; Ellis, R.
- Nuclear Fusion, Vol. 51, Issue 10
Non-linear wave-particle interactions and fast ion loss induced by multiple Alfvén eigenmodes in the DIII-D tokamak
journal, May 2014
- Chen, Xi; Kramer, G. J.; Heidbrink, W. W.
- Nuclear Fusion, Vol. 54, Issue 8
Orbit-following fusion alpha wall load simulation for ITER scenario 4 including full orbit effects
journal, September 2012
- Snicker, A.; Sipilä, S.; Kurki-Suonio, T.
- Nuclear Fusion, Vol. 52, Issue 9
Ripple‐induced energetic particle loss in tokamaks
journal, August 1996
- White, R. B.; Goldston, R. J.; Redi, M. H.
- Physics of Plasmas, Vol. 3, Issue 8
Redistribution of high energy alpha particles due to sawteeth with partial reconnection
journal, March 2013
- Farengo, R.; Ferrari, H. E.; García-Martínez, P. L.
- Nuclear Fusion, Vol. 53, Issue 4
Simulations of fast ion wall loads in ASDEX Upgrade in the presence of magnetic perturbations due to ELM-mitigation coils
journal, September 2012
- Asunta, O.; Äkäslompolo, S.; Kurki-Suonio, T.
- Nuclear Fusion, Vol. 52, Issue 9
Theory of Alfvén-slow frequency gaps and discovery of Alfvén-slow eigenmodes in tokamaks
journal, August 2019
- Cheng, C. Z.; Kramer, G. J.; Podesta, M.
- Physics of Plasmas, Vol. 26, Issue 8
Collisional stochastic ripple diffusion of alpha particles and beam ions on TFTR
journal, October 1995
- Redi, M. H.; Zarnstorff, M. C.; White, R. B.
- Nuclear Fusion, Vol. 35, Issue 10
Study of thermonuclear Alfv n instabilities in next step burning plasma proposals
journal, July 2003
- Gorelenkov, N. N.; Berk, H. L.; Budny, R.
- Nuclear Fusion, Vol. 43, Issue 7
Basic physics of Alfvén instabilities driven by energetic particles in toroidally confined plasmas
journal, May 2008
- Heidbrink, W. W.
- Physics of Plasmas, Vol. 15, Issue 5
Confinement of High-Energy Trapped Particles in Tokamaks
journal, August 1981
- Goldston, R. J.; White, R. B.; Boozer, A. H.
- Physical Review Letters, Vol. 47, Issue 9
Fast-wave heating of a two-component plasma
journal, October 1975
- Stix, T. H.
- Nuclear Fusion, Vol. 15, Issue 5
Development and validation of a predictive model for the pedestal height
journal, May 2009
- Snyder, P. B.; Groebner, R. J.; Leonard, A. W.
- Physics of Plasmas, Vol. 16, Issue 5
Chapter 5: Physics of energetic ions
journal, June 2007
- Fasoli, A.; Gormenzano, C.; Berk, H. L.
- Nuclear Fusion, Vol. 47, Issue 6
Enhanced Localized Energetic-Ion Losses Resulting from Single-Pass Interactions with Alfvén Eigenmodes
journal, February 2013
- Chen, X.; Austin, M. E.; Fisher, R. K.
- Physical Review Letters, Vol. 110, Issue 6
Hamiltonian theory of adiabatic motion of relativistic charged particles
journal, September 2007
- Tao, Xin; Chan, Anthony A.; Brizard, Alain J.
- Physics of Plasmas, Vol. 14, Issue 9
Systematic linear-stability assessment of Alfvén eigenmodes in the presence of fusion α-particles for ITER-like equilibria
journal, June 2015
- Rodrigues, P.; Figueiredo, A.; Ferreira, J.
- Nuclear Fusion, Vol. 55, Issue 8
Alpha particle physics in a tokamak burning plasma experiment
journal, May 2002
- Heidbrink, W. W.
- Physics of Plasmas, Vol. 9, Issue 5
Dependence of alpha-particle-driven Alfvén eigenmode linear stability on device magnetic field strength and consequences for next-generation tokamaks
journal, March 2019
- Tolman, E. A.; Loureiro, N. F.; Rodrigues, P.
- Nuclear Fusion, Vol. 59, Issue 4
Saturation of Alfvén modes in tokamak plasmas investigated by Hamiltonian mapping techniques
journal, March 2017
- Briguglio, S.; Schneller, M.; Wang, X.
- Nuclear Fusion, Vol. 57, Issue 7
Kinetic theory of low-frequency Alfvén modes in tokamaks
journal, November 1996
- Zonca, Fulvio; Chen, Liu; Santoro, Robert A.
- Plasma Physics and Controlled Fusion, Vol. 38, Issue 11
The CASTOR-K Code, Recent Developments and Applications
journal, February 2015
- Nabais, F.; Borba, D.; Coelho, R.
- Plasma Science and Technology, Vol. 17, Issue 2
Energetic particle physics in fusion research in preparation for burning plasma experiments
journal, November 2014
- Gorelenkov, N. N.; Pinches, S. D.; Toi, K.
- Nuclear Fusion, Vol. 54, Issue 12
A guiding-center Fokker–Planck collision operator for nonuniform magnetic fields
journal, September 2004
- Brizard, Alain J.
- Physics of Plasmas, Vol. 11, Issue 9
Simulation of localized fast-ion heat loads in test blanket module simulation experiments on DIII-D
journal, November 2013
- Kramer, G. J.; McLean, A.; Brooks, N.
- Nuclear Fusion, Vol. 53, Issue 12
Modelling TF ripple loss of alpha particles in TFTR DT experiments
journal, December 1995
- Redi, M. H.; Budny, R. V.; Darrow, D. S.
- Nuclear Fusion, Vol. 35, Issue 12
Fast ion power loads on ITER first wall structures in the presence of NTMs and microturbulence
journal, July 2011
- Kurki-Suonio, T.; Asunta, O.; Hirvijoki, E.
- Nuclear Fusion, Vol. 51, Issue 8
Stability of Alfvén gap modes in burning plasmas
journal, June 1992
- Betti, R.; Freidberg, J. P.
- Physics of Fluids B: Plasma Physics, Vol. 4, Issue 6
High fusion performance from deuterium-tritium plasmas in JET
journal, February 1999
- Keilhacker, M.; Gibson, A.; Gormezano, C.
- Nuclear Fusion, Vol. 39, Issue 2
Ripple modifications to alpha transport in tokamaks
journal, October 2018
- Catto, Peter J.
- Journal of Plasma Physics, Vol. 84, Issue 5
Overview of the SPARC tokamak
journal, September 2020
- Creely, A. J.; Greenwald, M. J.; Ballinger, S. B.
- Journal of Plasma Physics, Vol. 86, Issue 5
Effect of the magnetic field ripple on diffusion in Tokamaks
journal, December 1972
- Stringer, T. E.
- Nuclear Fusion, Vol. 12, Issue 6
Effect of the European design of TBMs on ITER wall loads due to fast ions in the baseline (15 MA), hybrid (12.5 MA), steady-state (9 MA) and half-field (7.5 MA) scenarios
journal, October 2016
- Kurki-Suonio, T.; Äkäslompolo, S.; Särkimäki, K.
- Nuclear Fusion, Vol. 56, Issue 11
Introduction to the interaction between energetic particles and Alfven eigenmodes in toroidal plasmas
journal, December 2018
- Todo, Y.
- Reviews of Modern Plasma Physics, Vol. 3, Issue 1
Effects of q ( r ) on the alpha particle ripple loss in TFTR
journal, May 1998
- Zweben, S. J.; Darrow, D. S.; Batha, S. H.
- Nuclear Fusion, Vol. 38, Issue 5
Ripple-trapped loss of neutral-beam-injected fast ions in JT-60U
journal, November 1992
- Tobita, K.; Tani, K.; Neyatani, Y.
- Physical Review Letters, Vol. 69, Issue 21
Power loads to ITER first wall structures due to fusion alphas in a non-axisymmetric magnetic field including the presence of MHD modes
journal, August 2013
- Snicker, A.; Hirvijoki, E.; Kurki-Suonio, T.
- Nuclear Fusion, Vol. 53, Issue 9
Figures / Tables found in this record: