Title: 3D two-temperature magnetohydrodynamic modeling of fast thermal quenches due to injected impurities in tokamaks

Journal Article · · Nuclear Fusion
 [1];  [2];  [3];  [2];  [1]
  1. Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
  2. General Atomics, San Diego, CA (United States)
  3. SLs2 Consulting, San Diego, CA (United States)
+ Show Author Affiliations

Here, an integrated model for the ionization, radiation, and advection of impurities in the extended-magnetohydrodynamic code M3D-C1 is described. This implementation makes use of the KPRAD model, which calculates bremsstrahlung radiation and impurity ionization, recombination, and radiation rates using a model in which the density of each charge state is advanced separately. The integrated model presented here allows the independent evolution of electron and ion temperatures, which is necessary to accurately model cases where the electron temperature drops more quickly than the electron-ion thermal equilibration time. This model is used to simulate the disruption of a model NSTX discharge caused by the introduction of argon impurities, using physically realistic resistivity. Despite well-mixed impurities, contraction of the current channel is found to lead to magnetohydrodynamic instabilities that result in stochastization of the magnetic field, a fast thermal quench, and localized parallel electric fields that can exceed the axisymmetric values by a factor of five for brief periods.

Research Organization:
Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States)
Sponsoring Organization:
USDOE
Grant/Contract Number:
AC02-05CH11231; AC02-09CH11466; FG02-95ER54309
OSTI ID:
1480324
Journal Information:
Nuclear Fusion, Journal Name: Nuclear Fusion Journal Issue: 1 Vol. 59; ISSN 0029-5515
Publisher:
IOP ScienceCopyright Statement
Country of Publication:
United States
Language:
English

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Cited By (3)

Shattered pellet injection simulations with NIMROD journal April 2019
Axisymmetric simulations of vertical displacement events in tokamaks: A benchmark of M3D-C 1 , NIMROD, and JOREK journal February 2020
Axisymmetric benchmarks of impurity dynamics in extended-magnetohydrodynamic simulations journal April 2019

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70 PLASMA PHYSICS AND FUSION TECHNOLOGY
disruption mitigation
disruptions
tokamaks