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arXiv · 1403.2773

Hybrid Vlasov-MHD models: Hamiltonian vs. non-Hamiltonian

Cesare Tronci·Emanuele Tassi·Enrico Camporeale·Philip J. Morrison
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Abstract

This paper investigates hybrid kinetic-MHD models, where a hot plasma (governed by a kinetic theory) interacts with a fluid bulk (governed by MHD). Different nonlinear coupling schemes are reviewed, including the pressure-coupling scheme (PCS) used in modern hybrid simulations. This latter scheme suffers from being non-Hamiltonian and to not exactly conserve total energy. Upon adopting the Vlasov description for the hot component, the non-Hamiltonian PCS and a Hamiltonian variant are compared. Special emphasis is given to the linear stability of Alfvén waves, for which it is shown that a spurious instability appears at high frequency in the non-Hamiltonian version. This instability is removed in the Hamiltonian version.

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Cesare Tronci, Emanuele Tassi, Enrico Camporeale, Philip J. Morrison. 2014-06-12. Hybrid Vlasov-MHD models: Hamiltonian vs. non-Hamiltonian. https://doi.org/10.1088/0741-3335%2F56%2F9%2F095008

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