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DOE OSTI · 1708848

Rapidly-convergent flux-surface shape parameterization

Arbon, Ryan·Candy, Jeff·Belli, Emily A.
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Abstract

We propose a novel flux-surface parameterization suitable for local MHD equilibrium calculations with strongly-shaped flux surfaces. The method is based on a systematic expansion in a small number of intuitive shape parameters, and reduces to the well-known Miller D-shaped parameterization in the limit where some of the coefficients are set to zero. Here, the new parameterization is valid for up-down asymmetric plasmas and provides an improvement to the Miller form. Simultaneously, the method is rapidly convergent and requires only about half the number of shape parameters as a general Fourier representation in the pedestal.

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Arbon, Ryan, Candy, Jeff, Belli, Emily A.. 2020-10-20. Rapidly-convergent flux-surface shape parameterization. https://doi.org/10.1088/1361-6587%2Fabc63b

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