Damage threshold and dumping of liquid metal mirror for laser fusion power plant based on fast ignition

• Project/Area Number: 25420887
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Nuclear fusion studies
• Research Institution: Osaka University
• Principal Investigator: Norimatsu Takayoshi 大阪大学, レーザーエネルギー学研究センタ, 教授 (50135753)
• Co-Investigator(Kenkyū-buntansha): JITSUNO Takahisa 大阪大学, レーザーエネルギー額研究センター, 教授 (30162811) ; KUNUGI Tomoaki 京都大学, 原子核工学専攻, 教授 (40301832) ; SHIMADA Yoshinori 財団法人レーザー技術総合研究所, 研究員 (80250091) ; MOTOJKOSH Shinji 財団法人レーザー技術総合研究所, 研究員 (20270580) ; FURUKAWA Hiroyuki 財団法人レーザー技術総合研究所, 研究員 (70222271)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Project Status: Completed (Fiscal Year 2015)
• Budget Amount: ¥5,070,000 (Direct Cost: ¥3,900,000、Indirect Cost: ¥1,170,000); Fiscal Year 2015: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000); Fiscal Year 2014: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000); Fiscal Year 2013: ¥1,950,000 (Direct Cost: ¥1,500,000、Indirect Cost: ¥450,000)
• Keywords: 液体金属ミラー / レーザー核融合 / 最終光学系 / 表面張力波 / 高速点火 / 慣性核融合 / レーザー / 炉工学 / 液体金属 / ミラー / 炉工

Outline of Final Research Achievements

In a future laser fusion reactor, the final optics made with multi-coated mirror will be used. To avoid degradation by neutrons, the final optics will be replaced during short halt of laser operation. Since bundled beam will be used for the ignition beam, it is hard to exchange mirrors in a short time. Use of liquid mirror allows automatic recovery of damaged surface and stabilizes deformation of base materials.
We experimentally simulate vibration of surface during laser irradiation using Hg. Results indicated that the surface vibration dumps in 100ms after laser irradiation with the fluence of 2/3 of the damage limit. This result shows the liquid metal mirror can be used in future laser fusion power plants.

Research Products

• [Journal Article] RELAXATION OF SURFACE TENSION WAVES ON A LIQUID METAL MIRROR FOR A FAST-IGNITION LASER FUSION PLANT (2016)
  • Author(s): Takayoshi Norimatsu1, Oleg Kotyaev, Yoshinori Shimada, Shinri Kurahashi, Shinji Motikoshi, Katsuhiro Mikami, Kei Sasaki, Takahisa Jitsuno, Kohei Yamanoi, Hiroyuki Furukawa and Tomoaki Kunugi
  • Journal Title: Fusion Science and Technology Volume: 65
  • Peer Reviewed
• [Presentation] レーザー核融合炉に於ける高速点火ビーム用液体金属ミラーの適用範囲 (2015)
  • Author(s): 乗松孝好
  • Organizer: 第35回レーザー学会年次大会
  • Place of Presentation: 東海大学（東京都品川区）
  • Year and Date: 2015-01-11 – 2015-01-12
• [Presentation] Shallow liquid metal mirror for ignition beam of laser fusion power plant (2014)
  • Author(s): Takayoshi Norimatsu
  • Organizer: American Nuclear Society
  • Place of Presentation: Anaheim CA, USA
  • Year and Date: 2014-11-09 – 2014-11-13
• [Presentation] Fundamental study of wave propagation on liquid surface related to IFE mirror (2014)
  • Author(s): Yuji Moriyama
  • Organizer: American Nuclear Society
  • Place of Presentation: Anaheim CA, USA
  • Year and Date: 2014-11-09 – 2014-11-13
• [Presentation] レーザー核融合実験炉概念設計の現状 (2013)
  • Author(s): 乗松孝好、神前康次、白神宏之、藤田尚徳、岡野邦彦、炉設計委員会委員
  • Organizer: プラズマ・核融合学会
  • Place of Presentation: 東京工業大学
  • Invited