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arXiv · 1810.09500

Full-$f$ gyrokinetic simulation of turbulence in a helical open-field-line plasma

Eric L. Shi·Gregory W. Hammett·Timothy Stoltzfus-Dueck·Ammar Hakim
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Abstract

Curvature-driven turbulence in a helical open-field-line plasma is investigated using electrostatic five-dimensional gyrokinetic continuum simulations in an all-bad-curvature helical-slab geometry. Parameters for a National Spherical Torus Experiment scrape-off-layer plasma are used in the model. The formation and convective radial transport of plasma blobs is observed, and it is shown that the radial particle-transport levels are several times higher than diffusive Bohm-transport estimates. By reducing the strength of the poloidal magnetic field, the profile of the heat flux to the divertor plate is observed to broaden.

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Eric L. Shi, Gregory W. Hammett, Timothy Stoltzfus-Dueck, Ammar Hakim. 2018-10-22. Full-$f$ gyrokinetic simulation of turbulence in a helical open-field-line plasma. https://doi.org/10.1063/1.5074179

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