Multiregion approach to freeboundary threedimensional tokamak equilibria and resistive wall instabilities
Freeboundary 3D tokamak equilibria and resistive wall instabilities are calculated using a new resistive wall model in the twofluid M3DC1 code. In this model, the resistive wall and surround ing vacuum region are included within the computational domain. Our implementation contrasts with the method typically used in fluid codes in which the resistive wall is treated as a boundary condition on the computational domain boundary and has the advantage of maintaining purely local coupling of mesh elements. We use this new capability to simulate perturbed, freeboundary non axisymmetric equilibria; the linear evolution of resistive wall modes; and the linear and nonlinear evolution of axisymmetric vertical displacement events (VDEs). Calculated growth rates for a resistive wall mode with arbitrary wall thickness are shown to agree well with the analytic theory. Equilibrium and VDE calculations are performed in diverted tokamak geometry, at physically real istic values of dissipation, and with resistive walls of finite width. Simulations of a VDE disruption extend into the currentquench phase, in which the plasma becomes limited by the first wall, and strong currents are observed to flow in the wall, in the SOL, and from the plasma to the wall.
 Authors:

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;
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;
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^{[3]}
 General Atomics, La Jolla, CA (United States)
 Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
 Rensselaer Polytechnic Inst., Troy, NY (United States)
 Publication Date:
 Grant/Contract Number:
 FC0204ER54698; FG0295ER54309; AC0209CH11466; SC0006617
 Type:
 Accepted Manuscript
 Journal Name:
 Physics of Plasmas
 Additional Journal Information:
 Journal Volume: 23; Journal Issue: 5; Journal ID: ISSN 1070664X
 Publisher:
 American Institute of Physics (AIP)
 Research Org:
 General Atomics, San Diego, CA (United States)
 Sponsoring Org:
 USDOE
 Country of Publication:
 United States
 Language:
 English
 Subject:
 70 PLASMA PHYSICS AND FUSION TECHNOLOGY
 OSTI Identifier:
 1371710
 Alternate Identifier(s):
 OSTI ID: 1254030
Ferraro, N. M., Jardin, S. C., Lao, L. L., Shephard, M. S., and Zhang, F.. Multiregion approach to freeboundary threedimensional tokamak equilibria and resistive wall instabilities. United States: N. p.,
Web. doi:10.1063/1.4948722.
Ferraro, N. M., Jardin, S. C., Lao, L. L., Shephard, M. S., & Zhang, F.. Multiregion approach to freeboundary threedimensional tokamak equilibria and resistive wall instabilities. United States. doi:10.1063/1.4948722.
Ferraro, N. M., Jardin, S. C., Lao, L. L., Shephard, M. S., and Zhang, F.. 2016.
"Multiregion approach to freeboundary threedimensional tokamak equilibria and resistive wall instabilities". United States.
doi:10.1063/1.4948722. https://www.osti.gov/servlets/purl/1371710.
@article{osti_1371710,
title = {Multiregion approach to freeboundary threedimensional tokamak equilibria and resistive wall instabilities},
author = {Ferraro, N. M. and Jardin, S. C. and Lao, L. L. and Shephard, M. S. and Zhang, F.},
abstractNote = {Freeboundary 3D tokamak equilibria and resistive wall instabilities are calculated using a new resistive wall model in the twofluid M3DC1 code. In this model, the resistive wall and surround ing vacuum region are included within the computational domain. Our implementation contrasts with the method typically used in fluid codes in which the resistive wall is treated as a boundary condition on the computational domain boundary and has the advantage of maintaining purely local coupling of mesh elements. We use this new capability to simulate perturbed, freeboundary non axisymmetric equilibria; the linear evolution of resistive wall modes; and the linear and nonlinear evolution of axisymmetric vertical displacement events (VDEs). Calculated growth rates for a resistive wall mode with arbitrary wall thickness are shown to agree well with the analytic theory. Equilibrium and VDE calculations are performed in diverted tokamak geometry, at physically real istic values of dissipation, and with resistive walls of finite width. Simulations of a VDE disruption extend into the currentquench phase, in which the plasma becomes limited by the first wall, and strong currents are observed to flow in the wall, in the SOL, and from the plasma to the wall.},
doi = {10.1063/1.4948722},
journal = {Physics of Plasmas},
number = 5,
volume = 23,
place = {United States},
year = {2016},
month = {5}
}