Experimental investigation of vapor shielding effects on plasma-facing materials using the double plasma gun device

2013 Fiscal Year Final Research Report

• Project/Area Number: 23760809
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Nuclear fusion studies
• Research Institution: University of Hyogo
• Principal Investigator: KIKUCHI Yusuke 兵庫県立大学, 工学(系)研究科(研究院), 准教授 (00433326)
• Project Period (FY): 2011 – 2013
• Keywords: 磁化プラズマガン / ELM / プラズマ対向壁 / 蒸気遮蔽効果 / パルス熱負荷

Research Abstract

We have studied simulation experiments of ELM-like pulsed plasma loads using a magnetized coaxial plasma gun (MCPG) at Univ. of Hyogo. The performance of the MCPG device has been improved to simulate transient heat and particle loads such as edge localized modes (ELMs). Surface modifications of tungsten (W) materials for plasma-facing components in fusion reactors due to repetitive pulsed plasma irradiation have been investigated. In particular, effects of pre-plasma exposure on W cracking due to ELM-like pulsed plasma bombardment have been evaluated for the first time. It has been found that He-induced W Fuzz exhibited a better resistance to surface cracking. On the other hand, a unique experiment using two MCPG devices of so-called double plasma gun to understand vapor shielding effects on the material erosion has been constructed. The first experiment to clarify vapor shielding effects quantitatively has been started.

Research Products

• [Journal Article] Characterization of Gun Plasma Penetrated into a Steady State Plasma Device (2013)
  • Author(s): S. Kajita, T. Akiyama, T. Nihashi, M. Osaka, N. Ohno, Y. Kikuchi, I. Sakuma, M. Nagata
  • Journal Title: IEEE Transactions on Plasma Science Volume: Vol. 41 Pages: 3122-3128
  • Peer Reviewed
• [Journal Article] Surface cracking and melting of different tungsten grades under transient heat and particle loads in a magnetized coaxial plasma gun (2013)
  • Author(s): Y. Kikuchi, I. Sakuma, D. Iwamoto, Y. Kitagawa, N. Fukumoto, M. Nagata, Y. Ueda
  • Journal Title: Journal of Nuclear Materials Volume: Vol. 438 Pages: S715-718
  • Peer Reviewed
• [Journal Article] Development of Steady/Transient Dual Plasma Irradiation Device Using a Plasma Gun (2013)
  • Author(s): S. Kajita, N. Ohno, T. Akiyama, T. Nihashi, T. Uchiyama, M. Osaka, Y. Kikuchi and M. Nagata
  • Journal Title: Journal of Nuclear Materials Volume: Vol. 438 Pages: S707-710
  • Peer Reviewed
• [Journal Article] Response of fuzzy tungsten surfaces to pulsed plasma bombardment (2013)
  • Author(s): D. Nishijima, R. P. Doerner, D. Iwamoto, Y. Kikuchi, M. Miyamoto, M. Nagata, I. Sakuma, K. Shoda and Y. Ueda
  • Journal Title: Journal of Nuclear Materials Volume: Vol. 434 Pages: 230-234
  • Peer Reviewed
• [Journal Article] Influences of ELM-like Pulsed Plasma Bombardment on Deuterium Retention in Tungsten (2011)
  • Author(s): D. Nishijima, Y. Kikuchi, M. Nakatsuka, M.J. Baldwin, R.P. Doerner, M. Nagata, Y. Ueda
  • Journal Title: Physica Scripta Volume: Vol. T145 Pages: 014053 (4pp)
  • Peer Reviewed
• [Journal Article] Surface damage characteristics of CFC and tungsten with repetitive ELM-like pulsed plasma irradiation (2011)
  • Author(s): Y. Kikuchi, D. Nishijima, M. Nakatsuka, K. Ando, T. Higashi, Y. Ueno, M. Ishihara, K. Shoda, M. Nagata, T. Kawai, Y. Ueda, N. Fukumoto, R.P. Doerner
  • Journal Title: Journal of Nuclear Materials Volume: Vol. 415 Pages: S55-S58
  • Peer Reviewed
• [Journal Article] Effects of Pre-Plasma Exposure on Tungsten Surface Cracking Due to ELM-like Pulsed Plasma Bombardment (2011)
  • Author(s): D. Nishijima, Y. Kikuchi, M. Nakatsuka, R.P. Doerner, M. Nagata, Y. Ueda
  • Journal Title: Fusion Science and Technology Volume: Vol. 60 Pages: 1447-1450
  • Peer Reviewed
• [Presentation] Experimental investigation of vapor shielding effects induced by ELM-like pulsed plasma loads using the double plasma gun device (2014)
  • Author(s): I. Sakuma, Y. Kikuchi, Y. Kitagawa, Y. Asai, K. Onishi, N. Fukumoto, M. Nagata
  • Organizer: 21st International Conference on Plasma Surface Interactions in Controlled Fusion Devices
  • Place of Presentation: Kanazawa, Japan
  • Year and Date: 20140526-30
• [Presentation] Surface modifications on toughened, fine-grained, recrystallized tungsten with repetitive ELM-like pulsed plasma irradiation (2014)
  • Author(s): Y. Kikuchi, I. Sakuma, Y. Kitagawa, Y. Asai, K. Onishi, N. Fukumoto, M. Nagata, Y. Ueda, H. Kurishita
  • Organizer: 21st International Conference on Plasma Surface Interactions in Controlled Fusion Devices
  • Place of Presentation: Kanazawa, Japan
  • Year and Date: 20140526-30
• [Presentation] Measurement of Transient Heat and Particle loads in NAGDIS-PG (2014)
  • Author(s): D. Sato, N. Ohno, M. Osaka, S. Kajitaa, Y. Kikuchi
  • Organizer: 21st International Conference on Plasma Surface Interactions in Controlled Fusion Devices
  • Place of Presentation: Kanazawa, Japan
  • Year and Date: 20140526-30
• [Presentation] Recent results of ELM simulation experiments on a magnetized coaxial plasma gun (2014)
  • Author(s): Y. Kikuchi, I. Sakuma, Y. Kitagawa,Y. Asai, K. Onishi, N. Fukumoto, M. Nagata, Y. Ueda
  • Organizer: Japan-US Workshop on "Heat Removal and Plasma Material Interactions for Fusion"
  • Place of Presentation: Livermore, USA
  • Year and Date: 20140107-08
• [Presentation] Characterization of CT injector developed for simulation of ELM-like pulse heat loads on divertor materials (2013)
  • Author(s): I. Sakuma, Y. Kitagawa, Y. Asai, K. Onishi, Y. Kikuchi, N. Fukumoto and T. Kanki
  • Organizer: US-Japan Workshop on "Advanced Control and Confinement Improvement of Innovative Compact Toroidal Configurations"
  • Place of Presentation: Kobe, Japan
  • Year and Date: 20130924-26
• [Presentation] Simulation Experiments of ELM-like Transient Heat and Particle Loads using a Magnetized Coaxial Plasma Gun (2012)
  • Author(s): Y. Kikuchi, I. Sakuma, D. Iwamoto, Y. Kitagawa, K. Shoda, N. Fukumoto, M. Nagata, Y. Ueda, S. Suzuki
  • Organizer: Abs. of 24th IAEA Fusion Energy Conference (FEC)
  • Place of Presentation: San Diego, USA
  • Year and Date: 20121008-13
• [Remarks]
  • URL: http://www.eng.u-hyogo.ac.jp/eecs/ykikuchi/kikuchi.html