Abstract Details
Abstracts
Author: Nathaniel M Ferraro
Requested Type: Poster
Submitted: 2023-03-31 13:39:04
Co-authors: S.C. Jardin, A. Kleiner, M.L. Reinke, R. Sweeney, B.C. Lyons, C. Zhao
Contact Info:
Princeton Plasma Physics Laboratory
100 Stellarator Rd
Princeton, NJ 08543
United States
Abstract Text:
Reactor-scale tokamaks must be designed to mitigate and withstand the large forces, thermal loads, and runaway electron beams associated with disruptions. Recent and planned developments in the M3D-C1 code aim to allow tightly coupled models of the interaction between the plasma dynamics, runaway electron beams, surrounding conducting structures, and impurity injection via pellets and gas injection to provide a high-fidelity, whole-facility disruption modeling capability that can be used for design validation of reactor-scale tokamaks. These developments include the implementation of a fluid model for runaway electrons, a capability to mesh complex conducting structures such as coils, vessels, and blanket modules using non-axisymmetric, anisotropic conductivity. Some of these capabilities have been applied to disruption modeling in a number of tokamaks, including DIII-D, JET, ITER, and KSTAR. Here we present fully three-dimensional magnetohydrodynamic (MHD) simulations of mitigated and unmitigated disruptions in NSTX, NSTX-U, and SPARC model discharges. Ionization, recombination, and radiation from injected gas is calculated self-consistently with the MHD evolution using a coronal non-equilibrium model. NSTX(-U) simulations, in which impurities are present in the core ab initio, show the rapid onset of MHD instabilities due to a contracting current profile, which leads to a thermal quench with significant conducted losses and a rapid vertical displacement of the plasma. SPARC simulations, in which poloidally and toroidally localized gas injection sources are included, instead show efficient radiation from the edge and a slow rate of vertical displacement, which minimizes conducted losses to the divertor at the cost of high radiative loads on the first wall.
Work supported by the Center for Tokamak Transients Simulations SciDAC, Commonwealth Fusion Systems, and by the US Department of Energy under contract DE-AC0204CH11466 and the INFUSE program.
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