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DOE OSTI · 3017854

Extending near-axis equilibria in $\mathtt{DESC}$

Panici, Dario Giovanni [Princeton Univ., NJ (United States)] (ORCID:0000000307364360)·Rodríguez, Eduardo [Max Planck Institute for Plasma Physics, Greifswald (Germany)] (ORCID:0000000214180466)·Conlin, Rory [Univ. of Maryland, College Park, MD (United States)] (ORCID:0000000183662111)·Dudt, Daniel William [Thea Energy, Inc., Kearney, NJ (United States)] (ORCID:0000000245573529)·Kolemen, Egemen [Princeton Univ., NJ (United States); Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States)] (ORCID:0000000342123247)
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Abstract

The near-axis description of optimised stellarator fields has proven to be a powerful tool both for the design and understanding of this magnetic confinement concept. The description consists of an asymptotic model of the equilibrium in the distance from its centremost axis, and is thus only approximate. Any practical application therefore requires the eventual construction of a global equilibrium. This paper presents a novel way of constructing global equilibria using the DESC code that guarantees the correct asymptotic behaviour imposed by a given near-axis construction. The theoretical underpinnings of this construction are carefully presented, and benchmarking examples provided. This opens the door to an efficient coupling of the near-axis framework and that of global equilibria for future optimisation efforts.

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BibTeXRIS

Panici, Dario Giovanni [Princeton Univ., NJ (United States)] (ORCID:0000000307364360), Rodríguez, Eduardo [Max Planck Institute for Plasma Physics, Greifswald (Germany)] (ORCID:0000000214180466), Conlin, Rory [Univ. of Maryland, College Park, MD (United States)] (ORCID:0000000183662111), Dudt, Daniel William [Thea Energy, Inc., Kearney, NJ (United States)] (ORCID:0000000245573529), Kolemen, Egemen [Princeton Univ., NJ (United States); Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States)] (ORCID:0000000342123247). 2026-01-26. Extending near-axis equilibria in $\mathtt{DESC}$. https://doi.org/10.1017/s0022377825100901

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