Three-dimensional structure and dynamic response of streamers in plasma turbulence

2022 Fiscal Year Final Research Report

• Project/Area Number: 17K06994
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Nuclear fusion studies
• Research Institution: Kyushu University
• Principal Investigator: Yamada Takuma 九州大学, 基幹教育院, 教授 (90437773)
• Project Period (FY): 2017-04-01 – 2023-03-31
• Keywords: 乱流計測 / 非線形結合 / ストリーマー

Outline of Final Research Achievements

In plasma turbulence research, it is important to understand the nature of streamer, which is one of the meso-scale structures. On linear plasma device, PANTA, of Kyushu University, streamer, its mediator, which has an important role for streamer formation, and its carrier waves, which form the streamer structure, have been observed three dimensionally and their axial structures were clarified. In addition, by using new analyzing methods, nonlinear coupling in the azimuthal direction was confirmed, and local information of the azimuthal wave number was partially obtained.

Free Research Field

プラズマ物理学

Academic Significance and Societal Importance of the Research Achievements

核融合発電の実現にはプラズマ乱流の理解し制御することが求められる。中でもメゾスケール構造は乱流輸送に大きな影響を与え、例えばメゾスケール構造の一種であるストリーマー構造はプラズマ内の輸送を増大させ、閉じ込めを劣化させてしまう。本研究では直線プラズマに発生するストリーマー構造を数多くの計測点や様々な解析手法によって3次元的に観測し、その詳細を明らかにした。特にこれまでのスペクトル解析・バイスペクトル解析を発展させた新しい解析手法はストリーマーの構造を明らかにするだけでなく、プラズマ乱流の精密計測実験の先駆けとなり大いに波及効果を生み出す。