PPPL-5081

Zakharov, Leonic E.; Li, Xujing

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DOE OSTI · 1182720

PPPL-5081

Zakharov, Leonic E.·Li, Xujing

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Abstract

This paper formulates the Tokamak Magneto-Hydrodynamics (TMHD), initially outlined by X. Li and L.E. Zakharov [Plasma Science and Technology, accepted, ID:2013-257 (2013)] for proper simulations of macroscopic plasma dynamics. The simplest set of magneto-hydrodynamics equations, sufficient for disruption modeling and extendable to more refined physics, is explained in detail. First, the TMHD introduces to 3-D simulations the Reference Magnetic Coordinates (RMC), which are aligned with the magnetic field in the best possible way. The numerical implementation of RMC is adaptive grids. Being consistent with the high anisotropy of the tokamak plasma, RMC allow simulations at realistic, very high plasma electric conductivity. Second, the TMHD splits the equation of motion into an equilibrium equation and the plasma advancing equation. This resolves the 4 decade old problem of Courant limitations of the time step in existing, plasma inertia driven numerical codes. The splitting allows disruption simulations on a relatively slow time scale in comparison with the fast time of ideal MHD instabilities. A new, efficient numerical scheme is proposed for TMHD.

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70 PLASMA PHYSICS AND FUSION TECHNOLOGY Disruptions Equilibrium, MHD Equilibrium, MHD - Toroidal Finite Element Method Kink Instability Magnetohydrodynamics (MHD)MHD Instability Tokamaks

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BibTeX RIS

Zakharov, Leonic E., Li, Xujing. 2014-10-17. PPPL-5081. https://www.osti.gov/biblio/1182720

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