Exploration of magnetic perturbation effects on advanced divertor configurations in NSTX-U

Frerichs, H.; Schmitz, O.; Waters, I.; Canal, G. P.; Evans, T. E.; Feng, Y.; Soukhanovskii, V. A.

doi:10.1063/1.4954816

Title: Exploration of magnetic perturbation effects on advanced divertor configurations in NSTX-U

Journal Article · 01 June 2016 · Physics of Plasmas

DOI: https://doi.org/10.1063/1.4954816 · OSTI ID:1399721

Frerichs, H. ^[1]; Schmitz, O. ^[1];

^[1]; Canal, G. P. ^[2];

^[2]; Feng, Y. ^[3]; Soukhanovskii, V. A. ^[4]

Univ. of Wisconsin, Madison, WI (United States)
General Atomics, San Diego, CA (United States)
Max Planck Inst. for Plasma Physics, Greifswald (Germany)
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

The control of divertor heat loads - both steady state and transient - remains a key challenge for the successful operation of ITER and FNSF. Magnetic perturbations provide a promising technique to control ELMs (transients), but understanding their detailed impact is difficult due to their symmetry breaking nature. One approach for reducing steady state heat loads are so called 'advanced divertors' which aim at optimizing the magnetic field configuration: the snowflake and the (super-)X-divertor. It is likely that both concepts - magnetic perturbations and advanced divertors - will have to work together, and we explore their inter- action based on the NSTX-U setup. An overview of different divertor con gurations under the impact of magnetic perturbations is presented, and the resulting impact on plasma edge transport is investigated with the EMC3-EIRENE code. Variations in size of the magnetic footprint of the perturbed separatrix are found, which is related to the level of flux expansion on the divertor target. Non-axisymmetric peaking of the heat flux related to the perturbed separatrix is found at the outer strike point, but only in locations where flux expansion is not too large.

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Research Organization:: Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)

Sponsoring Organization:: USDOE

Grant/Contract Number:: AC52-07NA27344; FC02-04ER54698; SC0012315

OSTI ID:: 1399721

Alternate ID(s):: OSTI ID: 1259743

Report Number(s):: LLNL-JRNL-739361; TRN: US1702971

Journal Information:: Physics of Plasmas, Vol. 23, Issue 6; ISSN 1070-664X

Publisher:: American Institute of Physics (AIP)Copyright Statement

Country of Publication:: United States

Language:: English

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Exploration of magnetic perturbation effects on advanced divertor configurations in NSTX-U Frerichs, H.; Waters, I.; Schmitz, O. Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States) https://doi.org/10.11578/1366498	dataset	January 2016
Exploration of magnetic perturbation effects on advanced divertor configurations in NSTX-U Frerichs, H.; Waters, I.; Schmitz, O. Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States) https://doi.org/10.11578/1366498	dataset	January 2016
Exploration of magnetic perturbation effects on advanced divertor configurations in NSTX-U Frerichs, H.; Waters, I.; Schmitz, O. Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States) https://doi.org/10.11578/1562062	dataset	January 2016
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Exploration of magnetic perturbation effects on advanced divertor configurations in NSTX-U Frerichs, H.; Waters, I.; Schmitz, O. Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States) https://doi.org/10.11578/1562062	dataset	January 2016

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Exploration of magnetic perturbation effects on advanced divertor configurations in NSTX-U Frerichs, H.; Waters, I.; Schmitz, O. Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States) https://doi.org/10.11578/1562062	dataset	January 2016
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Exploration of magnetic perturbation effects on advanced divertor configurations in NSTX-U Frerichs, H.; Waters, I.; Schmitz, O. Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States) https://doi.org/10.11578/1562062	dataset	January 2016