Improvements in a Tracer-Encapsulated Solid Pellet and Its Injector for More Advanced Plasma Diagnostics

10th Asia Plasma and Fusion Association Conference

Tamura, Naoki^1 ; Sudo, Shigeru^2 ; Suzuki, Chihiro^1 ; Funaba, Hisamichi^1 ; Takagi, Masaru^3 ; Satoh, Nakahiro^3 ; Hayashi, Hiromi^1 ; Maeno, Hiroya^1 ; Yokota, Mitsuhiro^1 ; Ogawa, Hideki^1

National Institute for Fusion Science, 322-6 Oroshi-cho, Toki-shi, Gifu

509-5292, Japan^1

Chubu University, 1200 Matsumoto-cho, Kasugai-shi, Aichi

487-8501, Japan^2

Hamamatsu Photonics Inc., 1820 Kurematsu-cho, Hamamatsu-shi, Shizuoka

431-1202, Japan^3

关键词: Double layered;    High-temperature plasmas;    Impurity sources;    Impurity transport;    Large Helical Device;    Unique features;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/823/1/012003/pdf
DOI  :  10.1088/1742-6596/823/1/012003

来源: IOP

【 摘 要 】

A Tracer-Encapsulated Solid Pellet (TESPEL) has been developed for promoting a precise study of the impurity transport in a magnetically-confined high-temperature plasma. This paper gives a brief report of the recent improvements in the TESPEL and its injector for more advanced plasma diagnostics. The TESPEL can be considered as a double-layered impurity pellet. This structure enables us to produce a both poloidally and toroidally localized "tracer" impurity source in the plasma, and to specify the total amount of the tracer impurity deposited in the plasma precisely. Recent experiments on the Large Helical Device by using the TESPEL suggest that the importance of the impurity source location in the impurity transport study. Thus we have developed new-type TESPELs, which are greatly improved in regard to the above-mentioned unique features. In addition, we also developed a new TESPEL injector, which enables us to inject the TESPEL obliquely into the plasma. This injector can also contribute to a further shallower penetration of the TESPEL into the plasma.