Experimental verification of the physics of isotope effects mediated by turbulence nonlinearity

• Project/Area Number: 20K03901
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 14020:Nuclear fusion-related
• Research Institution: Kyoto University
• Principal Investigator: OHSHIMA Shinsuke 京都大学, エネルギー理工学研究所, 助教 (00469610)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Project Status: Completed (Fiscal Year 2022)
• Budget Amount: ¥4,290,000 (Direct Cost: ¥3,300,000、Indirect Cost: ¥990,000); Fiscal Year 2022: ¥520,000 (Direct Cost: ¥400,000、Indirect Cost: ¥120,000); Fiscal Year 2021: ¥520,000 (Direct Cost: ¥400,000、Indirect Cost: ¥120,000); Fiscal Year 2020: ¥3,250,000 (Direct Cost: ¥2,500,000、Indirect Cost: ¥750,000)
• Keywords: 水素同位体効果 / プラズマ / 乱流 / 帯状流 / 核融合 / 非線形 / プラズマ乱流 / 同位体効果 / 磁場閉じ込め / 計測

Outline of Research at the Start

近年注目されている、乱流の非線形性を介在し同位体効果が生じるという仮説の実験による実証を目指し、
A.　乱流の非線形特性の実験的観測による同位体効果発現機構の解明
B.　磁場配位制御による、非線形乱流を介在した、同位体効果への影響の検証
を目指す。軽/重水素同位体比を制御し、広いパラメータ領域で乱流と帯状流の非線形結合・競合過程の特性の応答を明らかにする。乱流、そして帯状流を直接観測し、多様な揺動解析手法を駆使し、乱流の素過程およびその非線形特性を評価する。さらに、乱流と帯状流の非線形結合・競合過程の制御ノブとして、磁場の幾何形状（磁場配位）を制御し、同位体効果に影響を与えうるか、解明を目指す。

Outline of Final Research Achievements

This study elucidates the hydrogen isotope effect on confinement characteristics in magnetic confinement fusion. The research focuses on two main objectives: experimentally observing the nonlinear characteristics of turbulence and verifying the influence of nonlinear turbulence on the isotope effect by controlling the magnetic field configuration. The study manipulates the isotope ratio of hydrogen and deuterium and examines the response of the nonlinear coupling and competition between turbulence and a zonal flow. A combined measurement system is used to directly observe turbulence and a zonal flow, utilizing various fluctuation analysis techniques to evaluate their fundemental and nonlinear characteristics. The study also investigates the impact of the isotope effect by controlling the geometric shape of the magnetic field configuration.

Academic Significance and Societal Importance of the Research Achievements

閉じ込め特性に対する“水素同位体効果”は、ITERおよび将来の核融合炉の設計・性能予測の基盤となる知見でありながら、その物理機構は未解明である．本研究は同位体効果は乱流の非線形性を介在して発現しているのか？という疑問に対して取り組む．これは、イオン質量の違いという単純な差異が、なぜ輸送の基礎的理解に反して輸送改善を生み出しうるのか？なぜ磁場配位に応じてその改善度が異なるのか？という，プラズマ・乱流物理を深化させる取り組みであり，この点に学術的意義を有する．同時に、エネルギー問題を決着する可能性のある核融合炉の設計・性能予測に不可欠な基盤的知見に資することから，重要な社会的意義がある．

Research Products

• [Journal Article] Three-dimensional dynamics of fluctuations appearing during pellet ablation process around a pellet in a fusion plasma experiment (2022)
  • Author(s): Ohshima S.、Suzuki T.、Matoike R.、Motojima G.、Kado S.、Mori A.、Miyashita A.、Kobayashi S.、Minami T.、Iwata A.、Qiu D.、Wang C.、Luo M.、Zhang P.、Kondo Y.、Nishino N.、Mizuuchi T.、Okada H.、Konoshima S.、Inagaki S.、Nagasaki K.
  • Journal Title: Scientific Reports Volume: 12 Issue: 1 Pages: 14204-14204
  • DOI: 10.1038/s41598-022-18239-z
  • Peer Reviewed / Open Access
• [Journal Article] Development and initial results of 320?GHz interferometer system in Heliotron J (2022)
  • Author(s): Zhang P.、Ohshima S.、Zhao H.、Deng C.、Kobayashi S.、Kado S.、Minami T.、Matoike R.、Miyashita A.、Iwata A.、Kondo Y.、Qiu D.、Wang C.、Luo M.、Konoshima S.、Inagaki S.、Okada H.、Mizuuchi T.、Nagasaki K.
  • Journal Title: Review of Scientific Instruments Volume: 93 Issue: 11 Pages: 113519-113519
  • DOI: 10.1063/5.0101808
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Development of dual X-mode Doppler reflectometry system in Heliotron J (2022)
  • Author(s): Kondo Y.、Ohshima S.、Kuwahara D.、Inoshita K.、Fukuda T.、Minami T.、Kado S.、Kobayashi S.、Konoshima S.、Mizuuchi T.、Okada H.、Tomita T.、Nagasaki K.
  • Journal Title: Journal of Instrumentation Volume: 17 Issue: 05 Pages: C05023-C05023
  • DOI: 10.1088/1748-0221/17/05/c05023
  • Peer Reviewed / Open Access
• [Journal Article] Development of dual X-mode Doppler reflectometry Q2 Q3 system in Heliotron J (2022)
  • Author(s): Y. Kondo, S. Ohshima, D. Kuwahara, K. Inoshita, T. Fukuda, T. Minami, S. Kado, S. Kobayashi, S. Konoshima, T. Mizuuchi, H. Okada, T. Tomita and K. Nagasaki
  • Journal Title: Journal of Instrumentation Volume: 18
  • Peer Reviewed
• [Journal Article] First Application of an InfraRed Imaging Video Bolometer to Heliotron J Plasma (2021)
  • Author(s): MIYASHITA Akira、MUKAI Kiyofumi、OHSHIMA Shinsuke、MATOIKE Ryota、PETERSON Byron J.、KOBAYASHI Shinji、OKADA Hiroyuki、KADO Shinichiro、MINAMI Takashi、MIZUUCHI Tohru、KONOSHIMA Shigeru、NAGASAKI Kazunobu
  • Journal Title: Plasma and Fusion Research Volume: 16 Issue: 0 Pages: 1202079-1202079
  • DOI: 10.1585/pfr.16.1202079
  • NAID: 130008053039
  • ISSN: 1880-6821
  • Year and Date: 2021-06-07
  • Peer Reviewed
• [Journal Article] Numerical analysis of heat load distribution in Heliotron J with magnetic field tracing and plasma transport modeling (2021)
  • Author(s): R Matoike, G. Kawamura, S. Ohshima, Y. Suzuki, M. Kobayashi, S. Masuzaki, S. Kobayashi, S. Kado, T. Minami, H. Okada, T. Mizuuchi, S. Konoshima, Y. Feng, H. Frerichs, K. Nagasaki
  • Journal Title: Plasma Phys. Control. Fusion Volume: 63 Issue: 11 Pages: 115002-115002
  • DOI: 10.1088/1361-6587/ac2069
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Numerical investigation into the peripheral energetic-particle-driven MHD modes in Heliotron J with free boundary hybrid simulation (2021)
  • Author(s): P. Adulsiriswad, Y. Todo, S. Kado, S. Yamamoto, S. Kobayashi, S. Ohshima, H. Okada, T. Minami, Y. Nakamura, A. Ishizawa, S. Konoshima, T. Mizuuchi and K. Nagasaki
  • Journal Title: Nucl. Fusion Volume: 61 Issue: 11 Pages: 116065-116065
  • DOI: 10.1088/1741-4326/ac2779
  • Peer Reviewed / Open Access
• [Journal Article] Role of pre-ionization in NBI plasma start-up of Heliotron J using non-resonant microwave heating (2021)
  • Author(s): S. Kobayashi, K. Nagasaki, K. Hada, T. Stange, H. Okada, T. Minami, S. Kado, S. Ohshima, K. Tokuhara, Y. Nakamura
  • Journal Title: Nucl. Fusion Volume: 61 Issue: 11 Pages: 116009-116009
  • DOI: 10.1088/1741-4326/ac2105
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Isotope effect on zonal flow and its configuration dependence in low-density electron-cyclotron-resonance heated plasmas in Heliotron J (2021)
  • Author(s): S. Ohshima, H. Okada, L. Zang, S. Kobayashi, T. Minami, S. Kado, P. Adulsiriswad, D. Qiu, R. Matoike, M. Luo, P. Zhang
  • Journal Title: Plasma Phys. Control. Fusion Volume: 63 Issue: 10 Pages: 104002-104002
  • DOI: 10.1088/1361-6587/ac1837
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Development of beam emission spectroscopy in the helically symmetric experiment stellarator (2021)
  • Author(s): Kobayashi S.、Kumar S. T. A.、Anderson F. S. B.、Deng C. B.、Likin K. M.、Talmadge J. N.、Ohshima S.、Anderson D. T.
  • Journal Title: Review of Scientific Instruments Volume: 92 Issue: 6 Pages: 063503-063503
  • DOI: 10.1063/5.0043596
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Sensitivity improvement of infrared imaging video bolometer for divertor plasma measurement (2021)
  • Author(s): Mukai K.、Peterson B. J.、Ezumi N.、Shigematsu N.、Ohshima S.、Miyashita A.、Matoike R.
  • Journal Title: Review of Scientific Instruments Volume: 92 Issue: 6 Pages: 063521-063521
  • DOI: 10.1063/5.0043664
  • NAID: 120007166309
  • Peer Reviewed
• [Journal Article] Development of a multi-channel 320 GHz interferometer for high density plasma measurement in Heliotron J (2021)
  • Author(s): Ohshima S.、Zhang P.、Kume H.、Deng C.、Miyashita A.、Kobayashi S.、Okada H.、Minami T.、Kado S.、Adulsiriswad P.、Qiu D.、Luo M.、Matoike R.、Suzuki T.、Konoshima S.、Mizuuchi T.、Nagasaki K.
  • Journal Title: Review of Scientific Instruments Volume: 92 Issue: 5 Pages: 053519-053519
  • DOI: 10.1063/5.0043581
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Spatial characterization of edge zonal flows in the TJ-II stellarator: the roles of plasma heating and isotope mass (2021)
  • Author(s): Losada U、Kobayashi T、Ohshima S、Cappa A、Van Milligen B、Liniers M、L?pez-Miranda B、Liu B、Pastor I、Silva C、Hidalgo C
  • Journal Title: Plasma Physics and Controlled Fusion Volume: 63 Issue: 4 Pages: 044002-044002
  • DOI: 10.1088/1361-6587/abe24b
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Phase tracking with Hilbert transform and nonlinear wave-wave coupling analysis on the HL-2A tokamak (2021)
  • Author(s): Zang L.G.、Ohshima S.、Qu Y.F.、Shi P.W.、Zhong W.L.、Hou Y.M.、Yan L.W.、Ji X.Q.、Li J.Q.、Yu D.L.、Shi Z.B.、Liu Yi、Yang Q.W.、Xu M.
  • Journal Title: Nuclear Fusion Volume: 61 Issue: 2 Pages: 026024-026024
  • DOI: 10.1088/1741-4326/abcfce
  • Int'l Joint Research
• [Journal Article] Development of a Multi-Channel 320 GHz Interferometer for High Density Plasma Measurement in Heliotron J (2021)
  • Author(s): S. Ohshima1,a), P. Zhang2, H. Kume2, C. Deng3,4, A. Miyashita2, S. Kobayashi1, H. Okada2, T. Minami2, S. Kado2, P. Adulsiriswad2, D. Qiu2, M. Luo2, R. Matoike2, T.Suzuki2, S. Konoshima1, T. Mizuuchi1, and K. Nagasaki1
  • Journal Title: Review of Scientific Instruments Volume: -
  • Int'l Joint Research
• [Journal Article] Magnetohydrodynamic hybrid simulation of Alfv?n eigenmodes in Heliotron J, a low shear helical axis stellarator/heliotron (2020)
  • Author(s): Adulsiriswad P.、Todo Y.、Yamamoto S.、Kado S.、Kobayashi S.、Ohshima S.、Okada H.、Minami T.、Nakamura Y.、Ishizawa A.、Konoshima S.、Mizuuchi T.、Nagasaki K.
  • Journal Title: Nuclear Fusion Volume: 60 Issue: 9 Pages: 096005-096005
  • DOI: 10.1088/1741-4326/ab9c4b
  • Peer Reviewed
• [Presentation] Characterisation of Turbulence. Zonal Flow, and Turbulent Transport Against Hydrogen Isotope Ratio in a Turus Plasma Experiment (2022)
  • Author(s): S.Ohshima
  • Organizer: 48th EPS conference on plasma physics
  • Int'l Joint Research / Invited
• [Presentation] ヘリオトロンJ配位制御実験の拡張 (2021)
  • Author(s): 大島慎介, 小林進二,山中雄太1, 的池遼太1, 宮下 顕1, 近藤恭斗2,井下圭1, 三好正博1,南貴司, 門信一郎, 岡田浩之, 水内亨, 木島滋, 長﨑百伸
  • Organizer: 先進ヘリカル研究会
• [Presentation] Isotope Effects on Nonlinear Turbulence System in a Torus Plasma (2020)
  • Author(s): S. Ohshima et al
  • Organizer: 4th Asia-Pacific Conference on Plasma Physics
  • Int'l Joint Research / Invited
• [Presentation] Development of multi-channel spectroscopic system for turbulence measurement (2020)
  • Author(s): A.Fujisawa, S.Ohshima
  • Organizer: The 11th International Symposium of Advanced Energy Science, 2020