Hostname: page-component-8448b6f56d-cfpbc Total loading time: 0 Render date: 2024-04-17T22:01:34.800Z Has data issue: false hasContentIssue false
  • English
  • Français

Hybrid simulation of NBI fast-ion losses due to the Alfvén eigenmode bursts in the Large Helical Device and the comparison with the fast-ion loss detector measurements

Part of: Focus on Fusion

Published online by Cambridge University Press:  03 November 2020

R. Seki Open the ORCID record for R. Seki [Opens in a new window] ,
Y. Todo Open the ORCID record for Y. Todo [Opens in a new window] ,
Y. Suzuki Open the ORCID record for Y. Suzuki [Opens in a new window] ,
K. Ogawa Open the ORCID record for K. Ogawa [Opens in a new window] ,
M. Isobe Open the ORCID record for M. Isobe [Opens in a new window] ,
D. A. Spong Open the ORCID record for D. A. Spong [Opens in a new window]  and
M. Osakabe Open the ORCID record for M. Osakabe [Opens in a new window]
R. Seki*
Affiliation:
National Institute for Fusion Science, National Institutes of Natural Sciences, Toki, Japan The Graduate University for Advanced Studies, SOKENDAI, Toki, Japan
Y. Todo
Affiliation:
National Institute for Fusion Science, National Institutes of Natural Sciences, Toki, Japan
Y. Suzuki
Affiliation:
National Institute for Fusion Science, National Institutes of Natural Sciences, Toki, Japan The Graduate University for Advanced Studies, SOKENDAI, Toki, Japan
K. Ogawa
Affiliation:
National Institute for Fusion Science, National Institutes of Natural Sciences, Toki, Japan The Graduate University for Advanced Studies, SOKENDAI, Toki, Japan
M. Isobe
Affiliation:
National Institute for Fusion Science, National Institutes of Natural Sciences, Toki, Japan The Graduate University for Advanced Studies, SOKENDAI, Toki, Japan
D. A. Spong
Affiliation:
Oak Ridge National Laboratory, Oak Ridge, USA
M. Osakabe
Affiliation:
National Institute for Fusion Science, National Institutes of Natural Sciences, Toki, Japan The Graduate University for Advanced Studies, SOKENDAI, Toki, Japan
*
†Email address for correspondence: seki.ryohsuke@nifs.ac.jp
Get access Rights & Permissions [Opens in a new window]

Abstract

The multiphase simulations are conducted with the kinetic-magnetohydrodynamics hybrid code MEGA to investigate the spatial and the velocity distributions of lost fast ions due to the Alfvén eigenmode (AE) bursts in the Large Helical Device plasmas. It is found that fast ions are lost along the divertor region with helical symmetry both before and during the AE burst except for the promptly lost particles. On the other hand, several peaks are present in the spatial distribution of lost fast ions along the divertor region. These peaks along the divertor region can be attributed to the deviation of the fast-ion orbits from the magnetic surfaces due to the grad-B and the curvature drifts. For comparison with the velocity distribution of lost fast ions measured by the fast-ion loss detector (FILD), the ‘numerical FILD’ which solves the Newton–Lorentz equation is constructed in the MEGA code. The velocity distribution of lost fast ions detected by the numerical FILD during AE burst is in good qualitative agreement with the experimental FILD measurements. During the AE burst, fast ions with high energy (100–180 keV) are detected by the numerical FILD, while co-going fast ions lost to the divertor region are the particles with energy lower than 50 keV.

Keywords

fusion plasmaplasma simulation
Type
Research Article
Information
Journal of Plasma Physics , Volume 86 , Issue 5 , October 2020 , 905860520
Check for updates
Copyright
Copyright © The Author(s), 2020. Published by Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Bierwage, A., Shinohara, K., Todo, Y., Aiba, N., Ishikawa, M., Matsunaga, G., Takechi, M. & Yagi, M. 2018 Simulations tackle abrupt massive migrations of energetic beam ions in a tokamak plasma. Nat. Commun. 9 (1), 1–11.CrossRefGoogle Scholar
Bierwage, A. & Todo, Y. 2017 Benchmark of multi-phase method for the computation of fast ion distributions in a tokamak plasma in the presence of low-amplitude resonant mhd activity. Comput. Phys. Commun. 220, 279–284.CrossRefGoogle Scholar
Briguglio, S., Vlad, G., Zonca, F. & Kar, C. 1995 Hybrid magnetohydrodynamic-gyrokinetic simulation of toroidal Alfvén modes. Phys. Plasmas 2 (10), 3711–3723.CrossRefGoogle Scholar
Burby, J. W. & Tronci, C. 2017 Variational approach to low-frequency kinetic-MHD in the current coupling scheme. Plasma Phys. Control. Fusion 59 (4), 045013.CrossRefGoogle Scholar
Fu, G., Park, W., Strauss, H., Breslau, J., Chen, J., Jardin, S. & Sugiyama, L. 2006 Global hybrid simulations of energetic particle effects on the $n= 1$ mode in tokamaks: internal kink and fishbone instability. Phys. Plasmas 13 (5), 052517.CrossRefGoogle Scholar
Fujiwara, Y., Kamio, S., Ogawa, K., Yamaguchi, H., Seki, R., Nuga, H., Nishitani, T., Isobe, M. & Osakabe, M. 2020 Enhancement of an e parallel b type neutral particle analyzer with high time resolution in the large helical device. J. Instrum. 15 (02), C02021.CrossRefGoogle Scholar
Harafuji, K., Hayashi, T. & Sato, T. 1989 Computational study of three-dimensional magnetohydrodynamic equilibria in toroidal helical systems. J. Comput. Phys. 81 (1), 169–192.CrossRefGoogle Scholar
Mett, R. & Mahajan, S. 1992 Kinetic theory of toroidicity-induced Alfvén eigenmodes. Phys. Fluids B 4 (9), 2885–2893.CrossRefGoogle Scholar
Nishimura, S., Todo, Y., Spong, D. A., Suzuki, Y. & Nakajima, N. 2013 Simulation study of Alfvén-eigenmode-induced energetic ion transport in LHD. Plasma Fusion Res. 8, 2403090–2403090.CrossRefGoogle Scholar
Nührenberg, C. 1999 Compressional ideal magnetohydrodynamics: unstable global modes, stable spectra, and Alfvén eigenmodes in Wendelstein 7-X-type equilibria. Phys. Plasmas 6 (1), 137–147.CrossRefGoogle Scholar
Ogawa, K., Isobe, M., Toi, K., Spong, D. A., Osakabe, M. & LHD Experiment Group 2012 Magnetic configuration effects on TAE-induced losses and a comparison with the orbit-following model in the large helical device. Nucl. Fusion 52 (9), 094013.CrossRefGoogle Scholar
Osakabe, M., Yamamoto, S., Toi, K., Takeiri, Y., Sakakibara, S., Nagaoka, K., Tanaka, K., Narihara, K. & the LHD Experimental Group 2006 Experimental observations of enhanced radial transport of energetic particles with Alfvén eigenmode on the LHD. Nucl. Fusion 46 (10), S911.CrossRefGoogle Scholar
Park, W., Parker, S., Biglari, H., Chance, M., Chen, L., Cheng, C.-Z., Hahm, T., Lee, W., Kulsrud, R., Monticello, D., et al. 1992 Three-dimensional hybrid gyrokinetic-magnetohydrodynamics simulation. Phys. Fluids B 4 (7), 2033–2037.CrossRefGoogle Scholar
Pinon, J., Todo, Y. & Wang, H. 2018 Effects of fast ions on interchange modes in the large helical device plasmas. Plasma Phys. Control. Fusion 60 (7), 075007.CrossRefGoogle Scholar
Sato, M. & Todo, Y. 2019 Effect of precession drift motion of trapped thermal ions on ballooning modes in helical plasmas. Nucl. Fusion 59 (9), 094003.CrossRefGoogle Scholar
Seki, R., Matsumoto, Y., Suzuki, Y., Watanabe, K. & Itagaki, M. 2008 Particle orbit analysis in the finite beta plasma of the large helical device using real coordinates. Plasma Fusion Res. 3, 016–016.CrossRefGoogle Scholar
Seki, R., Todo, Y., Suzuki, Y., Spong, D., Ogawa, K., Isobe, M. & Osakabe, M. 2019 Comprehensive magnetohydrodynamic hybrid simulations of Alfvén eigenmode bursts and fast-ion losses in the large helical device. Nucl. Fusion 59 (9), 096018.CrossRefGoogle Scholar
Spong, D., Carreras, B. & Hedrick, C. 1992 Linearized gyrofluid model of the alpha-destabilized toroidal Alfvén eigenmode with continuum damping effects. Phys. Fluids B 4 (10), 3316–3328.CrossRefGoogle Scholar
Suzuki, Y., Nakajima, N., Watanabe, K., Nakamura, Y. & Hayashi, T. 2006 Development and application of HINT2 to helical system plasmas. Nucl. Fusion 46 (11), L19.CrossRefGoogle Scholar
Todo, Y. 2016 Multi-phase hybrid simulation of energetic particle driven magnetohydrodynamic instabilities in tokamak plasmas. New J. Phys. 18 (11), 115005.CrossRefGoogle Scholar
Todo, Y. 2019 Critical energetic particle distribution in phase space for the Alfvén eigenmode burst with global resonance overlap. Nucl. Fusion 59 (9), 096048.CrossRefGoogle Scholar
Todo, Y., Murakami, S., Yamamoto, T., Fukuyama, A., Spong, D. A., Yamamoto, S., Osakabe, M. & Nakajima, N. 2010 a Numerical analyses of energetic particles in LHD. Fusion Sci. Technol. 58 (1), 277–288.CrossRefGoogle Scholar
Todo, Y., Nakajima, N., Sato, M. & Miura, H. 2010 b Simulation study of ballooning modes in the large helical device. Plasma Fusion Res. 5, S2062–S2062.CrossRefGoogle Scholar
Todo, Y. & Sato, T. 1998 Linear and nonlinear particle-magnetohydrodynamic simulations of the toroidal Alfvén eigenmode. Phys. Plasmas 5 (5), 1321–1327.CrossRefGoogle Scholar
Todo, Y., Sato, T., Watanabe, K., Watanabe, T. & Horiuchi, R. 1995 Magnetohydrodynamic vlasov simulation of the toroidal Alfvén eigenmode. Phys. Plasmas 2 (7), 2711–2716.CrossRefGoogle Scholar
Todo, Y., Seki, R., Spong, D., Wang, H., Suzuki, Y., Yamamoto, S., Nakajima, N. & Osakabe, M. 2017 Comprehensive magnetohydrodynamic hybrid simulations of fast ion driven instabilities in a large helical device experiment. Phys. Plasmas 24 (8), 081203.CrossRefGoogle Scholar
Todo, Y., Van Zeeland, M., Bierwage, A. & Heidbrink, W. 2014 Multi-phase simulation of fast ion profile flattening due to Alfvén eigenmodes in a DIII-D experiment. Nucl. Fusion 54 (10), 104012.CrossRefGoogle Scholar
Todo, Y., Van Zeeland, M., Bierwage, A., Heidbrink, W. & Austin, M. E. 2015 Validation of comprehensive magnetohydrodynamic hybrid simulations for Alfvén eigenmode induced energetic particle transport in DIII-D plasmas. Nucl. Fusion 55 (7), 073020.CrossRefGoogle Scholar
Todo, Y., Van Zeeland, M. & Heidbrink, W. 2016 Fast ion profile stiffness due to the resonance overlap of multiple Alfvén eigenmodes. Nucl. Fusion 56 (11), 112008.CrossRefGoogle Scholar
Wang, H., Todo, Y., Ido, T. & Suzuki, Y. 2018 Chirping and sudden excitation of energetic-particle-driven geodesic acoustic modes in a large helical device experiment. Phys. Rev. Lett. 120 (17), 175001.CrossRefGoogle Scholar
Wang, H., Todo, Y., Oasakabe, M., Ido, T. & Suzuki, Y. 2019 Simulation of energetic particle driven geodesic acoustic modes and the energy channeling in the large helical device plasmas. Nucl. Fusion 59 (9), 096041.CrossRefGoogle Scholar
Wang, X., Zonca, F. & Chen, L. 2010 Theory and simulation of discrete kinetic beta induced Alfvén eigenmode in tokamak plasmas. Plasma Phys. Control. Fusion 52 (11), 115005.CrossRefGoogle Scholar