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arXiv · 2305.01487

The muphyII Code: Multiphysics Plasma Simulation on Large HPC Systems

Florian Allmann-Rahn·Simon Lautenbach·Magnus Deisenhofer·Rainer Grauer
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Abstract

Collsionless astrophysical and space plasmas cover regions that typically display a separation of scales that exceeds any code's capabilities. To help address this problem, the muphyII code utilizes a hierarchy of models with different inherent scales, unified in an adaptive framework that allows stand-alone use of models as well as a model-based dynamic and adaptive domain decomposition. This requires ensuring excellent conservation properties, careful treatment of inner-domain model boundaries for model coupling, and robust time stepping algorithms, especially with the use of electron subcycling. This multi-physics approach is implemented in the muphyII code, tested on different scenarios of space plasma reconnection and evaluated against space probe data and higher-fidelity simulation results from literature. Adaptive model refinement is highlighted in particular, and a hybrid model with kinetic ions, pressure-tensor fluid electrons, and Maxwell fields is appraised.

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Florian Allmann-Rahn, Simon Lautenbach, Magnus Deisenhofer, Rainer Grauer. 2023-05-02. The muphyII Code: Multiphysics Plasma Simulation on Large HPC Systems. https://doi.org/10.1016/j.cpc.2023.109064

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