Non-linear Simulations of MHD Instabilities in Tokamaks Including Eddy Current Effects and Perspectives for the Extension to Halo Currents

Joint Varenna-Lausanne International Workshop 2014

Hoelzl, M.^1 ; Huijsmans, G.T.A.^2 ; Merkel, P.^1 ; Atanasiu, C.^3 ; Lackner, K.^1 ; Nardon, E.^4 ; Aleynikova, K.^2 ; Liu, F.^2 ; Strumberger, E.^1 ; McAdams, R.^5,6 ; Chapman, I.^6 ; Fil, A.^4

Max-Planck-Institute for Plasmaphysics, Boltzmannstr. 2, Garching

85748, Germany^1

ITER Organisation, Route de Vinon sur Verdon, St-Paul-lez-Durance, France^2

Association EURATOM-MEdC Romania, PO Box MG-36, Magurele, Bucharest, Romania^3

CEA, IRFM, CEA Cadarache, St Paul-lez-Durance

F-13108, France^4

York Plasma Institute, University of York, York

YO10 5DD, United Kingdom^5

Culham Science Centre, Abingdon

OX14 3DB, United Kingdom^6

关键词: Conducting structure;    Eddy-current effects;    Large-scale instability;    Magnetic perturbation;    Non-linear finite elements;    Nonlinear properties;    Nonlinear simulations;    Vertical displacement events;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/561/1/012011/pdf
DOI  :  10.1088/1742-6596/561/1/012011

来源: IOP

【 摘 要 】

The dynamics of large scale plasma instabilities can be strongly influenced by the mutual interaction with currents flowing in conducting vessel structures. Especially eddy currents caused by time-varying magnetic perturbations and halo currents flowing directly from the plasma into the walls are important. The relevance of a resistive wall model is directly evident for Resistive Wall Modes (RWMs) or Vertical Displacement Events (VDEs). However, also the linear and non-linear properties of most other large-scale instabilities may be influenced significantly by the interaction with currents in conducting structures near the plasma. The understanding of halo currents arising during disruptions and VDEs, which are a serious concern for ITER as they may lead to strong asymmetric forces on vessel structures, could also benefit strongly from these non-linear modeling capabilities. Modeling the plasma dynamics and its interaction with wall currents requires solving the magneto-hydrodynamic (MHD) equations in realistic toroidal X-point geometry consistently coupled with a model for the vacuum region and the resistive conducting structures. With this in mind, the non-linear finite element MHD code JOREK [1, 2] has been coupled [3] with the resistive wall code STARWALL [4], which allows us to include the effects of eddy currents in 3D conducting structures in non-linear MHD simulations. This article summarizes the capabilities of the coupled JOREK-STARWALL system and presents benchmark results as well as first applications to non-linear simulations of RWMs, VDEs, disruptions triggered by massive gas injection, and Quiescent H-Mode. As an outlook, the perspectives for extending the model to halo currents are described.