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arXiv · 2412.14962

ThinCurr: An open-source 3D thin-wall eddy current modeling code for the analysis of large-scale systems of conducting structures

Christopher Hansen·Alexander Battey·Anson Braun·Sander Miller·Michael Lagieski·Ian Stewart·Ryan Sweeney·Carlos Paz-Soldan
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Abstract

In this paper we present a new thin-wall eddy current modeling code, ThinCurr, for studying inductively-coupled currents in 3D conducting structures -- with primary application focused on the interaction between currents flowing in coils, plasma, and conducting structures of magnetically-confined plasma devices. The code utilizes a boundary finite element method on an unstructured, triangular grid to accurately capture device structures. The new code, part of the broader Open FUSION Toolkit, is open-source and designed for ease of use without sacrificing capability and speed through a combination of Python, Fortran, and C/C++ components. Scalability to large models is enabled through use of hierarchical off-diagonal low-rank compression of the inductance matrix, which is otherwise dense. Ease of handling large models of complicated geometry is further supported by automatic determination of supplemental elements through a greedy homology approach. A detailed description of the numerical methods of the code and verification of the implementation of those methods using cross-code comparisons against the VALEN code and Ansys commercial analysis software is shown.

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Christopher Hansen, Alexander Battey, Anson Braun, Sander Miller, Michael Lagieski, Ian Stewart, Ryan Sweeney, Carlos Paz-Soldan. 2024-12-19. ThinCurr: An open-source 3D thin-wall eddy current modeling code for the analysis of large-scale systems of conducting structures. https://doi.org/10.1016/j.cpc.2025.109713

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