Magnetic field topology modeling under resonant magnetic perturbations on EAST

In order to understand the mechanism by which the resonant magnetic perturbation (RMP) mitigates or suppresses the edge-localized mode (ELM), the topological study of the edge magnetic field in ELM mitigation or suppression phase is a critical issue. To model the three-dimensional magnetic field topology superposed RMP on Experimental Advanced Superconducting Tokamak, a numerical model using the field line tracing method for both vacuum and ideal plasma response approximations is proposed. Using the numerical model, the topological change and the penetration depth of the stochastic field lines in the edge magnetic field are studied in an RMP experiment. Comparing profiles of minimum ρ on edge stochastic field lines and the particle flux pattern, the ideal plasma response changes the field line penetration depth while remaining similar profile relative to vacuum approximation. To mitigate and suppress ELM strongly, the deep penetration of RMP fields and topological changes of the edge magnetic field is a key from our modeling.

[1]  X. Ji,et al.  Nonlinear Transition from Mitigation to Suppression of the Edge Localized Mode with Resonant Magnetic Perturbations in the EAST Tokamak. , 2016, Physical review letters.

[2]  Sudip K. Seal,et al.  PARVMEC: An Efficient, Scalable Implementation of the Variational Moments Equilibrium Code , 2016, 2016 45th International Conference on Parallel Processing (ICPP).

[3]  T. Evans,et al.  Connection between plasma response and resonant magnetic perturbation (RMP) edge localized mode (ELM) suppression in DIII-D , 2015 .

[4]  R. Fitzpatrick.  Linear and nonlinear response of a rotating tokamak plasma to a resonant error-field , 2014 .

[5]  G. Dif-Pradalier,et al.  Non-linear magnetohydrodynamic modeling of plasma response to resonant magnetic perturbations , 2013 .

[6]  P T Lang,et al.  First observation of edge localized modes mitigation with resonant and nonresonant magnetic perturbations in ASDEX Upgrade. , 2011, Physical review letters.

[7]  E. Nardon,et al.  Model for screening of resonant magnetic perturbations by plasma in a realistic tokamak geometry and its impact on divertor strike points , 2010, 1012.4015.

[8]  K. Spatschek,et al.  Numerical modeling of edge-localized-mode filaments on divertor plates based on thermoelectric currents. , 2010, Physical review letters.

[9]  M. Becoulet,et al.  Resonant magnetic perturbation experiments on MAST using external and internal coils for ELM control , 2010 .

[10]  D. Reiser,et al.  Free energy minimization approach to penetration of resonant magnetic perturbations in tokamaks , 2009 .

[11]  K. Spatschek,et al.  Footprint structures due to resonant magnetic perturbations in DIII-D , 2009 .

[12]  J. M. Bialek,et al.  Study of in-vessel nonaxisymmetric ELM suppression coil concepts for ITER , 2008 .

[13]  A. Polevoi,et al.  Numerical study of the resonant magnetic perturbations for Type I edge localized modes control in ITER , 2008 .

[14]  N Hawkes,et al.  Active control of type-I edge-localized modes with n=1 perturbation fields in the JET tokamak. , 2007, Physical review letters.

[15]  A. Boozer,et al.  Computation of three-dimensional tokamak and spherical torus equilibria , 2007 .

[16]  Keith H. Burrell,et al.  Edge stability and transport control with resonant magnetic perturbations in collisionless tokamak plasmas , 2006 .

[17]  M E Fenstermacher,et al.  Suppression of large edge-localized modes in high-confinement DIII-D plasmas with a stochastic magnetic boundary. , 2004, Physical review letters.

[18]  M. Sugihara,et al.  Characteristics of type I ELM energy and particle losses in existing devices and their extrapolation to ITER , 2003 .

[19]  P. Snyder,et al.  Ideal magnetohydrodynamic constraints on the pedestal temperature in tokamaks , 2003 .

[20]  P. Ghendrih,et al.  REVIEW ARTICLE: Theoretical and experimental investigations of stochastic boundaries in tokamaks , 1996 .

[21]  H. Zohm.  Edge localized modes (ELMs) , 1996 .

[22]  A. Bazzani,et al.  Poincaré map and anomalous transport in a magnetically confined plasma , 1989 .

[23]  L. Lao,et al.  Reconstruction of current profile parameters and plasma shapes in tokamaks , 1985 .

[24]  F. Wagner,et al.  Regime of Improved Confinement and High Beta in Neutral-Beam-Heated Divertor Discharges of the ASDEX Tokamak , 1982 .

[25]  J. Manickam,et al.  Ideal MHD stability calculations in axisymmetric toroidal coordinate systems , 1982 .

[26]  B. Chirikov.  A universal instability of many-dimensional oscillator systems , 1979 .