Hybrid Vlasov-MHD models: Hamiltonian vs. non-Hamiltonian
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 Alfv\'en 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.
Keywords
Cite
@article{arxiv.1403.2773,
title = {Hybrid Vlasov-MHD models: Hamiltonian vs. non-Hamiltonian},
author = {Cesare Tronci and Emanuele Tassi and Enrico Camporeale and Philip J. Morrison},
journal= {arXiv preprint arXiv:1403.2773},
year = {2014}
}
Comments
11 pages, 2 figures. To appear in Plasma Phys. Control. Fusion