Plasma and Fusion Research

Volume 19, 1403019 (2024)

Regular Articles

Implication of Parallel Velocity Gradient-Driven Instability with Hydrodynamic Electrons to SOL Width
Itsuki OYAMA and Yusuke KOSUGA1)
Interdisciplinary Graduate School of Engineering Science, Kyushu University, Kasuga, Fukuoka 816-8580, Japan
1)
Research Institute for Applied Mechanics, Kyushu University, Kasuga, Fukuoka 816-8580, Japan
(Received 29 September 2023 / Accepted 29 February 2024 / Published 2 May 2024)

Abstract

Herein, a new aspect of the parallel velocity gradient (PVG)- driven instability is explored. We present its linear stability analysis and investigate the transport properties of the instability, focusing on a specific electron motion called hydrodynamic. In the realm of hydrodynamic electrons, electron motions across the magnetic field are much faster than those along the magnetic field. This electron motion plays an important role in fluctuation transport. This analysis reveals that the PVG convective cell is newly excited, and its feature of particle transport is favorable, since the particle pinch by PVG with adiabatic electrons disappears.

Keywords

PVG instability, transport, hydrodynamic electron, scrape-off layer

DOI: 10.1585/pfr.19.1403019

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