Nuclear Fusion (Jan 2024)
Hydrogen removal by electron cyclotron wall conditioning with neon gas and its impact of tokamak plasma start-up on the QUEST spherical tokamak
- Masakatsu Fukumoto,
- Qilin Yue,
- Kazuaki Hanada,
- Shinichiro Kojima,
- Tomohide Nakano,
- Naoaki Yoshida,
- Ryuya Ikezoe,
- Yoshihiko Nagashima,
- Takeshi Ido,
- Takumi Onchi,
- Hiroshi Idei,
- Hiroki Iguchi,
- Takumi Komiyama,
- Taiichi Shikama,
- Akira Ejiri,
- Suguru Masuzaki,
- Mizuki Sakamoto,
- Yoshio Ueda,
- Kengoh Kuroda,
- Kaori Kono,
- Shun Shimabukuro,
- Aki Higashijima
Affiliations
- Masakatsu Fukumoto
- National Institutes for Quantum Science and Technology , Naka 801-1, Japan
- Qilin Yue
- ORCiD
- Interdisciplinary Graduate School of Engineering Sciences, Kyushu University , Kasuga 816-8580, Japan
- Kazuaki Hanada
- Research Institute for Applied Mechanics, Kyushu University , Kasuga 816-8580, Japan
- Shinichiro Kojima
- ORCiD
- National Institutes for Quantum Science and Technology , Naka 801-1, Japan
- Tomohide Nakano
- National Institutes for Quantum Science and Technology , Naka 801-1, Japan
- Naoaki Yoshida
- Research Institute for Applied Mechanics, Kyushu University , Kasuga 816-8580, Japan
- Ryuya Ikezoe
- ORCiD
- Research Institute for Applied Mechanics, Kyushu University , Kasuga 816-8580, Japan
- Yoshihiko Nagashima
- Research Institute for Applied Mechanics, Kyushu University , Kasuga 816-8580, Japan
- Takeshi Ido
- ORCiD
- Research Institute for Applied Mechanics, Kyushu University , Kasuga 816-8580, Japan
- Takumi Onchi
- ORCiD
- Research Institute for Applied Mechanics, Kyushu University , Kasuga 816-8580, Japan
- Hiroshi Idei
- ORCiD
- Research Institute for Applied Mechanics, Kyushu University , Kasuga 816-8580, Japan
- Hiroki Iguchi
- Graduate School of Engineering, Kyoto University , Kyoto 615-8540, Japan
- Takumi Komiyama
- Graduate School of Engineering, Kyoto University , Kyoto 615-8540, Japan
- Taiichi Shikama
- Graduate School of Engineering, Kyoto University , Kyoto 615-8540, Japan
- Akira Ejiri
- Graduate School of Frontier Sciences, The University of Tokyo , Kashiwa, 277-8561, Japan
- Suguru Masuzaki
- ORCiD
- National Institute for Fusion Science, National Institutes of Natural Sciences , Toki 509-5292, Japan
- Mizuki Sakamoto
- Plasma Research Center, University of Tsukuba , Tsukuba 305-8577, Japan
- Yoshio Ueda
- Graduate School of Engineering, Osaka University , Suita 565-0871, Japan
- Kengoh Kuroda
- ORCiD
- Japan Coast Guard Academy , Kure 737-8512, Japan
- Kaori Kono
- Research Institute for Applied Mechanics, Kyushu University , Kasuga 816-8580, Japan
- Shun Shimabukuro
- Research Institute for Applied Mechanics, Kyushu University , Kasuga 816-8580, Japan
- Aki Higashijima
- Research Institute for Applied Mechanics, Kyushu University , Kasuga 816-8580, Japan
- DOI
- https://doi.org/10.1088/1741-4326/ad3d6e
- Journal volume & issue
-
Vol. 64,
no. 6
p. 066022
Abstract
Electron cyclotron wall conditioning with neon gas (Ne-ECWC) has been performed on the normal conducting spherial tokamak QUEST with metal walls under a trapped particle configuration with O-mode EC waves including X-mode polarization with a frequency of 8.2 GHz and an injection power of 16 kW. The Ne-ECWC removes hydrogen from the wall with small neon retention. The Ne-ECWC decreases hydrogen recycling at the following tokamak discharges, contributing to an improvement of the following tokamak plasma start-up: the plasma current increases and the start-up timing of the plasma current shifts forward. However, defects such as voids and bubbles are formed on tungsten surface exposed to the Ne-ECWC plasma.
Keywords
