Simulation study of the energy channel and the particle radial transport due to the energetic particle driven geodesic acoustic mode

2021 Fiscal Year Final Research Report

• Project/Area Number: 18K13529
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 14020:Nuclear fusion-related
• Research Institution: National Institute for Fusion Science
• Principal Investigator: Wang Hao 核融合科学研究所, ヘリカル研究部, 助教 (30724760)
• Project Period (FY): 2018-04-01 – 2022-03-31
• Keywords: EGAMチャネリング / 測地線音響モード / バルクイオン加熱

Outline of Final Research Achievements

The energetic particle driven geodesic acoustic mode (EGAM) strongly affects the plasma heating efficiency by transferring energy from energetic particles to bulk plasma. The principal investigator investigated this phenomenon and obtained good achievements in the following 3 aspects. (1) For the first time, the anomalous bulk ion heating during EGAM activity is reproduced in simulation, and the mechanism is clarified with solid evidence. It is found that sideband resonance is dominant during the energy transfer from EGAM to the bulk ions, and the transit frequencies of resonant bulk ions are one-half of the EGAM frequency. (2) For the first time, the bulk ion heating efficiency of EGAM channeling is systematically investigated. These investigations are helpful for improving heating efficiency in the experiment. (3) The principal investigator extended his research field and investigated energetic particle driven instabilities in a quasi-axisymmetric stellarator named CFQS.

Free Research Field

プラズマ閉じ込め

Academic Significance and Societal Importance of the Research Achievements

本研究の学術的意義は、EGAMのエネルギーチャネルの物理機構を初めて解明したことにあります。これは、EGAMの理解を深めるだけでなく、磁場閉じ込め核融合の閉じ込めレベルのさらなる向上に貢献するものです。さらに、本研究の成果は、従来のステラレータだけでなく、トカマクや先進的なステラレータなど、他のタイプの磁気閉じ込め核融合装置にも適用可能であることがわかった。磁場閉じ込め核融合は、人類の将来のエネルギー問題を解決する鍵であるため、この研究の社会的意義は、人類の将来のエネルギー問題を解決するための新しいアイデアを提供することであると言えます。