Hostname: page-component-78c5997874-j824f Total loading time: 0 Render date: 2024-11-05T04:53:03.179Z Has data issue: false hasContentIssue false

Open problems of magnetic island control by electron cyclotron current drive

Published online by Cambridge University Press:  17 November 2016

D. Grasso*
Affiliation:
Istituto dei Sistemi Complessi – CNR, Via dei Taurini 19, 00185, Roma, Italy Dipartimento Energia, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129, Torino, Italy
E. Lazzaro
Affiliation:
Istituto di Fisica del Plasma ‘P. Caldirola’, CNR, 20125, Milano, Italy
D. Borgogno
Affiliation:
Dipartimento Energia, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129, Torino, Italy
L. Comisso
Affiliation:
Department of Astrophysical Sciences and Princeton Plasma Physics Laboratory, Princeton University, Princeton, NJ 08544, USA
*
Email address for correspondence: [email protected]

Abstract

This paper reviews key aspects of the problem of magnetic islands control by electron cyclotron current drive in fusion devices. On the basis of the ordering of the basic spatial and time scales of the magnetic reconnection physics, we present the established results, highlighting some of the open issues posed by the small-scale structures that typically accompany the nonlinear evolution of the magnetic islands and constrain the effect of the control action.

Type
Research Article
Copyright
© Cambridge University Press 2016 

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

Ara, G., Basu, B., Coppi, B., Laval, G., Rosenbluth, M. N. & Waddel, B. V. 1978 Magnetic reconnection and $m=1$ oscillations in current carrying plasmas. Ann. Phys. 112, 443476.Google Scholar
Aydemir, A. Y. 1992 Nonlinear studies of $m=1$ modes in high temperature plasmas. Phys. Fluids B 4, 3469.CrossRefGoogle Scholar
Berrino, J., Cirant, S., Gandini, F., Granucci, G., Lazzaro, E., Jannone, F., Smeulders, P. & D’Antona, G. 2006 Automatic real-time tracking and stabilization of magnetic islands in a tokamak using temperature fluctuations and ECW power. IEEE Trans. Nucl. Sci. 53, 1009.Google Scholar
Bertelli, N. & Westerhof, E. 2009 Consequences of finite transport on the effectiveness of eccd for neoclassical tearing mode stabilization in iter. Nucl. Fusion 49, 095018.CrossRefGoogle Scholar
Borgogno, D., Comisso, L., Lazzaro, E. & Grasso, D. 2014 Nonlinear response of magnetic islands to localized electron cyclotron current injection. Phys. Plasmas 21, 060704.Google Scholar
van den Brand, H., de Baar, M. R., Lopes Cardozo, N. J. & Westerhof, E. 2012 Integrated modelling of island growth, stabilization and mode locking: consequences for NTM control on ITER. Plasma Phys. Control. Fusion 54, 094003.CrossRefGoogle Scholar
Cafaro, E., Grasso, D., Pegoraro, F., Porcelli, F. & Saluzzi, A. 1998 Invariants and geometric structures in nonlinear hamiltonian magnetic reconnection. Phys. Rev. Lett. 80, 4430.Google Scholar
Callen, J. D., Qu, W. X., Siebert, K. D., Carreras, B. A., Shaing, K. C. & Spong, D. A. 1987 Neoclassical MHD equations, instabilities and transport in tokamaks. In Proceedings of IAEA Conference Plasma Physics and Controlled Nuclear Fusion Research, vol. 2, p. 157.Google Scholar
Comisso, L. & Grasso, D. 2016 Visco-resistive plasmoid instability. Phys. Plasmas 23, 032111.Google Scholar
Comisso, L., Grasso, D. & Waelbroeck, F. L. 2015 Extended theory of the Taylor problem in the plasmoid-unstable regime. Phys. Plasmas 22, 042109.Google Scholar
Comisso, L., Grasso, D., Waelbroeck, F. L. & Borgogno, D. 2013 Gyro-induced acceleration of magnetic reconnection. Phys. Plasmas 20, 092118.Google Scholar
Comisso, L. & Lazzaro, E. 2010 Two-dimensional effects in the problem of tearing modes control by electron cyclotron current drive. Nucl. Fusion 50, 125002.Google Scholar
Comisso, L., Lingam, M., Huang, Y.-M. & Bhattacharjee, A. 2016 General theory of the plasmoid instability. Phys. Plasmas 23, 100702.Google Scholar
DeLuca, F., Jacchia, A. & Lazzaro, E. 1986 Control of tearing mode instabilities by localized electron cyclotron wave heating. Phys. Fluids 29, 501.Google Scholar
Ebrahimi, F. & Raman, R. 2015 Plasmoids formation during simulations of coaxial helicity injection in the national spherical torus experiment. Phys. Rev. Lett. 114, 205003.CrossRefGoogle Scholar
Fevrier, O., Maget, P., Lütjens, H., Luciani, J. F., Decker, J., Giruzzi, G., Reich, M., Beyer, P., Lazzaro, E., Nowak, S.& The ASDEX Upgrade team 2016 First principles fluid modelling of magnetic island stabilization by electron cyclotron current drive (ECCD). Plasma Phys. Control. Fusion 58, 045015.Google Scholar
Fisch, N. J. & Boozer, A. H. 1980 Creating an asymmetric plasma resistivity with waves. Phys. Rev. Lett. 45, 720.Google Scholar
Fitzpatrick, R. 1995 Helical temperature perturbations associated with tearing modes in tokamak plasmas. Phys. Plasmas 2, 825.Google Scholar
Fitzpatrick, R. & Hender, T. C. 1994 Effect of a static external magnetic perturbation on resistive mode stability in tokamaks. Phys. Plasmas 11, 3337.Google Scholar
Fitzpatrick, R. & Porcelli, F. 2004 Collisionless magnetic reconnection with arbitrary guide field. Phys. Plasmas 11, 4713.CrossRefGoogle Scholar
Furth, H. P., Killeen, J. & Rosenbluth, M. N. 1963 Finite resistivity instabilities of a sheet pinch. Phys. Fluids 6, 459.CrossRefGoogle Scholar
Gantenbein, G., Zohm, H., Giruzzi, G., Günter, S., Leuterer, F., Maraschek, M., Meskat, J., Yu, Q., ASDEX Upgrade Team& ECRH-Group (AUG) 2000 Complete suppression of neoclassical tearing modes with current drive at the electron-cyclotron-resonance frequency in asdex upgrade tokamak. Phys. Rev. Lett. 85, 1242.CrossRefGoogle Scholar
Giruzzi, G., Zabiégo, M., Gianakon, T. A., Garbet, X., Cardinali, A. & Bernabei, S. 1999 Dynamical modelling of tearing mode stabilization by RF current drive. Nucl. Fusion 39, 107.Google Scholar
Grasso, D., Califano, F., Pegoraro, F. & Porcelli, F. 2000 Ion Larmor radius effects in collisionless reconnection. Plasma Phys. Rep. 26, 512.Google Scholar
Hegna, C. C. & Callen, J. D. 1997 On the stabilization of neoclassical magnetohydrodynamic tearing modes using localized current drive or heating. Phys. Plasmas 4, 29402946.Google Scholar
Isayama, A., Kamada, Y., Ide, S., Hamamatsu, K., Oikawa, T., Suzuki, T., Neyatani, Y., Ozeki, T., Kajiwara, K., Ikeda, Y.& The JT-60 team 2000 Complete stabilization of a tearing mode in steady state high- $\unicode[STIX]{x1D6FD}_{p}$ H-mode discharges by the first harmonic electron cyclotron heating/current drive on JT-60U. Plasma Phys. Control. Fusion 42, L37.Google Scholar
Ishii, Y., Azumi, M. & Smolyakov, A. I. 2007 Nonlinear evolution and deformation of driven magnetic islands in rotating plasmas. Nucl. Fusion 47, 1024.CrossRefGoogle Scholar
La Haye, R. J. 2006 Neoclassical tearing modes and their control. Phys. Plasmas 13, 055501.Google Scholar
LaSalle, J. P. 1959 Time optimal control systems. Proc. Natl Acad. Sci. USA 43, 573577.Google Scholar
Lazzaro, E., Comisso, L. & Valdettaro, L. 2010 Nonlinear response of a neoclassical four-field magnetic reconnection model to localized current drive. Phys. Plasmas 17, 052509.Google Scholar
Lazzaro, E. & Ramponi, G. 1996 Theory and calculation of current profile control near rational surfaces in a tokamak by electron cyclotron waves. Phys. Plasmas 3, 978.CrossRefGoogle Scholar
Liu, Y., Hastie, R. J. & Hender, T. C. 2012 Modification of $\unicode[STIX]{x1D6E5}^{\prime }$ by magnetic feedback and kinetic effects. Phys. Plasmas 19, 092510.Google Scholar
Loureiro, N. F., Schekochihin, A. A. & Cowley, S. C. 2007 Instability of current sheets and formation of plasmoid chains. Phys. Plasmas 14, 100703.Google Scholar
Mikhailovskii, A. B. 2003 Theory of magnetic island in tokamaks with accenting neoclassical tearing modes. Contrib. Plasma Phys. 43, 125.Google Scholar
Ottaviani, M. & Porcelli, F. 1993 Nonlinear collisionless magnetic reconnection. Phys. Rev. Lett. 71, 3802.Google Scholar
Petty, C. C., La Haye, R. J., Luce, T. C., Humphreys, D. A., Hyatt, A. W., Lohr, J., Prater, R., Strait, E. J. & Wade, M. R. 2004 Complete suppression of the $m=2/n=1$ neoclassical tearing mode using electron cyclotron current drive in DIII-D. Nucl. Fusion 44, 243.Google Scholar
Pletzer, A. & Perkins, F. W. 1999 Stabilization of neoclassical tearing modes using a continuous localized current drive. Phys. Plasmas 6, 1589.Google Scholar
Prater, R., La Haye, R. J., Lohr, J., Luce, T. C., Petty, C. C., Ferron, J. R., Humphreys, D. A., Strait, E. J., Perkins, F. W. & Harvey, R. W. 2003 Discharge improvement through control of neoclassical tearing modes by localized eccd in DIII-D. Nucl. Fusion 43, 1128.Google Scholar
Reiman, A. H. 1983 Suppression of magnetic islands by rf driven currents. Phys. Fluids 26, 1338.Google Scholar
Rutherford, P. H. 1973 Nonlinear growth of the tearing mode. Phys. Fluids 16, 1903.Google Scholar
Sauter, O. 2004 On the contribution of local current density to neoclassical tearing mode stabilization. Phys. Plasmas 11, 4808.Google Scholar
Smolyakov, A. & Lazzaro, E. 2004 On neoclassical effects in the theory of magnetic islands. Phys. Plasmas 11, 4354.Google Scholar
Smolyakov, A. I., Hirose, A., Lazzaro, E., Re, G. B. & Callen, J. D. 1995 Rotating nonlinear magnetic islands in a tokamak plasma. Phys. Plasmas 2, 1581.Google Scholar
Sun, G., Dong, C. & Duan, L. 2015 Effects of electron cyclotron current drive on the evolution of double tearing mode. Phys. Plasmas 22, 092509.CrossRefGoogle Scholar
Volpe, F. A. G., Austin, M. E., La Haye, R. J., Lohr, J., Prater, R., Strait, E. J. & Welander, A. S. 2009 Advanced techniques for neoclassical tearing mode control in DIII-D. Phys. Plasmas 16, 102502.CrossRefGoogle Scholar
Waelbroeck, F. L. 2009 Theory and observations of magnetic islands. Nucl. Fusion 49, 104025.Google Scholar
Wang, S., Ma, Z. W. & Zhang, W. 2016 Influence of driven current on resistive tearing mode in tokamaks. Phys. Plasmas 23, 052503.Google Scholar
Wilson, H. R., Alexander, M., Connor, J. W., Edwards, A. M., Gates, D., Grüber, O., Hastie, R. J., Hegna, C. C., Hender, T. C., La Haye, R. J. et al. 1996 The collisionality dependence of tokamak $\unicode[STIX]{x1D6FD}$ -limits. Plasma Phys. Control. Fusion 38, A149A163.Google Scholar
Zohm, H. et al. 1999 Nucl. Fusion 30, 577.Google Scholar