Nitrogen divertor plasma actively applying non-equilibrium characteristics of atomic and moelcular processes

2015 Fiscal Year Final Research Report

• Project/Area Number: 26610190
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Plasma science
• Research Institution: Tokyo Institute of Technology
• Principal Investigator: Akatsuka Hiroshi 東京工業大学, 原子炉工学研究所, 准教授 (50231808)
• Project Period (FY): 2014-04-01 – 2016-03-31
• Keywords: 再結合プラズマ / ダイバータプラズマ / 窒素プラズマ / 原子分子過程 / 非平衡性 / 核融合炉周辺領域

Outline of Final Research Achievements

We generate recombining nitrogen plasma plume by expansion of nitrogen arc into lower pressure vessel with a weak longitudinal magnetic field in a steady state. Spectroscopic observation reveals that the plasma has almost no component of molecular band spectra. Meanwhile, atomic nitrogen lines are observed with considerable intensity. The reason for this spectroscopic peculiarity is discussed in terms of chemical thermodynamics of the nitrogen thermal arc plasma and of non-equilibrium characteristics.
We also examined the dynamic characteristics of the nitrogen plasma. We experimentally examined its acceleration phenomena and potential drop along the open magnetic field line flowing supersonically. We found that admixture of nitrogen into helium increases the flowing velocity and moderates the potential drop.

Free Research Field

プラズマ理工学