Session KP01 - Poster Session III.
POSTER session, Tuesday afternoon, March 23
Exhibit Hall, GWCC
The study multiscale coupling phenomena in which particle kinetic physics involving small spatial and fast temporal scales can strongly affect the plasma global structure and long-time behavior is a major challenge especially at high-\beta. The difficulty of modeling such multiscale coupling processes stems from the disparate scales which are traditionally analyzed separately: the macroscale phenomena are generally studied using the fluid MHD framework, while microscale phenomena are best described by kinetic theories. To study multiscale coupling phenomena effectively, we have developed a new nonlinear kinetic-fluid model for high-\beta plasmas with multiple ion species. The model embeds important kinetic effects due to finite ion Larmor radii (FLR), wave-particle resonances, magnetic particle trapping, etc., in the framework of simple fluid descriptions. For ømega << ømega_ci, the kinetic-fluid model takes a simpler form in which the fluid equations of multiple ion species collapse into one-fluid, density and momentum, equations and a low-frequency generalized Ohm's law. The particle kinetic effects are introduced via plasma pressure tensors which are computed from particle distribution functions that are governed by kinetic equations. Ion FLR effects provide a parallel electric field, a perpendicular velocity that modifies the E \times B drift, and a gyroviscosity tensor, all of which are neglected in the usual MHD description. Applications of the kinetic-fluid model to laboratory and space plasmas will be demonstrated.