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  • Letter
  • Open Access

Critical gradient turbulence optimization toward a compact stellarator reactor concept

G. T. Roberg-Clark*, G. G. Plunk, P. Xanthopoulos, C. Nührenberg, S. A. Henneberg, and H. M. Smith

  • Max-Planck-Institut für Plasmaphysik, D-17491 Greifswald, Germany

  • *gar@ipp.mpg.de
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Phys. Rev. Research 5, L032030 – Published 5 September, 2023

DOI: https://doi.org/10.1103/PhysRevResearch.5.L032030

Abstract

Integrating turbulence into stellarator optimization is achieved by targeting the onset for the ion-temperature-gradient mode, highlighting effects of field line curvature, parallel connection length, local magnetic shear, and flux surface expansion. The result is two compact quasihelically symmetric stellarator configurations, one of which admits a set of modular coils, with significantly reduced turbulent heat fluxes compared to a known stellarator. This new configuration combines low values of neoclassical transport, good alpha particle confinement, and Mercier stability at a plasma beta of almost 2%.

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Outline

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Phys. Rev. Research 5, L032030– Published 5 September, 2023
  • Received 31 January 2023
  • Revised 23 June 2023
  • Accepted 16 August 2023
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI. Open access publication funded by the Max Planck Society.

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