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

作者：Tronci Cesare^*; Tassi Emanuele; Camporeale Enrico; Morrison Philip J

来源：Plasma Physics and Controlled Fusion, 2014, 56(9): 095008.

DOI：10.1088/0741-3335/56/9/095008

• magnetohydrodynamics
• Vlasov equation
• hybrid kinetic-MHD

This paper investigates hybrid kinetic-magnetohydrodynamic (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 is unable to 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 Alfven 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.

• 出版日期2014-9