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Interplay between magnetic shear and triangularity in ion temperature gradient and trapped electron mode dominated plasmas

Published online by Cambridge University Press:  18 January 2023

Gabriele Merlo Open the ORCID record for Gabriele Merlo [Opens in a new window]  and
Frank Jenko
Gabriele Merlo*
Affiliation:
Oden Institute for Computational Engineering and Sciences, The University of Texas at Austin, Austin, TX 78712, USA
Frank Jenko
Affiliation:
Oden Institute for Computational Engineering and Sciences, The University of Texas at Austin, Austin, TX 78712, USA Max-Planck-Institut für Plasmaphysik, Boltzmannstr. 2, D-85748 Garching, Germany
*
†Email address for correspondence: gmerlo@oden.utexas.edu
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Abstract

Local gyrokinetic simulations, performed with the GENE code, are used to investigate the interaction between (negative) triangularity $\delta$ and magnetic shear $s$, in both ion temperature gradient and trapped electron mode dominated plasmas. Magnetic shear turns out to influence in a non-trivial way the effect of negative triangularity. Also, $\delta <0$ is found to lead to a reduction of fluxes when $s>1$ but not anymore when shear is reduced. In certain parameter regimes, this effect can be inverted, up to obtaining higher fluxes when $\delta <0$ with respect to its $\delta >0$ counterpart.

Keywords

fusion plasmaplasma simulation
Type
Research Article
Information
Journal of Plasma Physics , Volume 89 , Issue 1 , February 2023 , 905890104
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Copyright
Copyright © The Author(s), 2023. Published by Cambridge University Press

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