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arXiv · 2012.06015

A parallel cut-cell algorithm for the free-boundary Grad-Shafranov problem

Shuang Liu·Qi Tang·Xian-Zhu Tang
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Abstract

A parallel cut-cell algorithm is described to solve the free-boundary problem of the Grad-Shafranov equation. The algorithm reformulates the free-boundary problem in an irregular bounded domain and its important aspects include a searching algorithm for the magnetic axis and separatrix, a surface integral along the irregular boundary to determine the boundary values, an approach to optimize the coil current based on a targeting plasma shape, Picard iterations with Aitken's acceleration for the resulting nonlinear problem, and a Cartesian grid embedded boundary method to handle the complex geometry. The algorithm is implemented in parallel using a standard domain-decomposition approach and a good parallel scaling is observed. Numerical results verify the accuracy and efficiency of the free-boundary Grad-Shafranov solver.

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BibTeXRIS

Shuang Liu, Qi Tang, Xian-Zhu Tang. 2020-12-10. A parallel cut-cell algorithm for the free-boundary Grad-Shafranov problem. https://arxiv.org/abs/2012.06015

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