Model of filament structure in a turbulent plasma edge

摘要

Edge turbulence called 'filaments' is one of the most interesting things to study in the field of plasma science. In this paper, it is demonstrated that a plasma model based on filaments could be made using a single-fluid MHD approach including ions and electrons. According to this model, non-uniform heating with, for example, neutral beam injection or cooling with local recycling makes a 'blob', and the blob extent is mainly along the magnetic field. Due to large thermal conduction parallel to the magnetic field the blob should have a shape called a 'filament'. During the extension process by which a blob becomes a filament it moves and/or rotates across the magnetic field due to an unbalanced jxB force. Using this model, the energy confinement time will be proportional to the total plasma current, if the filament generation rate is independent of the magnetic field.