Kikuchi, Mitsuru; Azumi, Masafumi*
Frontiers in Fusion Research, 2; Introduction to Modern Tokamak Physics, 402 Pages, 2015/09
This book is a textbook on modern tokamak plasma physics for graduate students and researchers based on our Reviews of Modern Physics (2012).
Kikuchi, Mitsuru; Medvedev, S.*; Takizuka, Tomonori*; Fasoli, A.*; Wu, Y.*; Diamond, P. H.*; Duan, X.*; Kishimoto, Yasuaki*; Hanada, Kazuaki*; 41 of others*
Europhysics Conference Abstracts (Internet), 39E, p.P4.179_1 - P4.179_4, 2015/06
Power and particle control in fusion reactor is quite a challenge and we have studied the negative triangularity tokamak (NTT) as an innovative concept to reduce the transient ELM heat load and the quasi steady-state heat load. A double-null NTT is stable to ideal MHD modes for a reactor relevant bN 3 while it is a magnetic hill configuration. In this paper, we report the configuration study of single-null NTT and its ideal MHD stability.
Kikuchi, Mitsuru; Fasoli, A.*; Takizuka, Tomonori*; Diamond, P. H.*; Medvedev, S.*; Wu, Y.*; Duan, X.*; Kishimoto, Yasuaki*; Hanada, Kazuaki*; Pueschel, M. J.*; et al.
Proceedings of 8th IAEA Technical Meeting on Steady State Operation of Magnetic Fusion Devices (CD-ROM), 20 Pages, 2015/05
The standard D shaped H-mode operation showed excellent plasma confinement ut has important issues of transient and steady state heat flux. To solbe this issues, we proposed new scenario using plasma shaping as one of possible scenario of future tokamak reactor.
AIP Conference Proceedings 1588, p.39 - 54, 2014/03
According to the invitation if 4th International Meeting on Frontiers of Physics (IMFP 2013), I will give a plenary talk among 8 speakers on plasma physics. The plasma physics made a significant progress to realize fusion relevant plasma. Hence, plasma physics becomes a fundamental discipline to be applied to various fields such as fusion, astrophysics (cosmology, solar, space, earth dynamo), laser plasma including plasma acceleration, and plasma processing. For example, first principle gyrokinetic simulation developed in fusion research is now applied to astrophyiscs. In this talk, topics in various application of plasma physics and basic physics of plasma are introduced.
Kikuchi, Mitsuru; Takizuka, Tomonori*; Furukawa, Masaru*
JPS Conference Proceedings (Internet), 1, p.015014_1 - 015014_4, 2014/03
Recent scaling of SOL e-folding length by Goldston shows pessimistic prediction to ITER and DEMO. This seems caused by the SOL acceleration mechanism found by Takizuka. In the negative D shaped plasma, this SOL acceleration may be significantly reduced. Negative D also has TEM eigen mode structure tilted poloidally and confinement in L mode is two times of L-mode. Based on these facts, we discuss possibility of negative D as a possible operation candidate of tokamak.
Urano, Hajime; Takizuka, Tomonori*; Aiba, Nobuyuki; Kikuchi, Mitsuru; Nakano, Tomohide; Fujita, Takaaki; Oyama, Naoyuki; Kamada, Yutaka; Hayashi, Nobuhiko; JT-60 Team
Nuclear Fusion, 53(8), p.083003_1 - 083003_8, 2013/08
Dependence of heat transport, edge pedestal and confinement on isotopic composition was investigated in conventional H-mode plasmas. Identical profiles for the electron density, electron temperature, and ion temperature were obtained for hydrogen and deuterium plasmas, whereas the required power clearly increased for hydrogen, which resulted in reduction of heat diffusivity for deuterium. The inverse of the ion-temperature-gradient (ITG) scale length which is required for a given ion heat diffusivity increased by a factor of approximately 1.2 for deuterium compared with that for hydrogen.
Nuclear Fusion, 53(2), P. 020402_1, 2013/03
On behalf of the Nuclear Fusion Board of Editors, I would like to introduce the 2011 and 2012 Nuclear Fusion prizes. Past winners are Dr T. Luce (2006), C. Angioni (2007), T. Evans (2008), S. Sabbagh (2009) and J. Rice (2010). The 2011 Nuclear Fusion prize is given to H. Urano et al, whose outstanding work studied dependences of the edge pedestal width. He is a first winner from Asia. The 2011 Nuclear Fusion prize is given to P. Diamond et al, for their seminal paper which synthesizes the original ideas of the authors and the way in which to confirm the central idea on the physics of intrinsic rotation in tokamaks.
Physics and Fusion, 168 Pages, 2013/03
"Physics and Fusion" has been published from Kyoto University Press in 2009. Its English edition is published from Springer Verlag London in 2011. Now Science Publisher of Chinese Academy of Science wants to publish Chinese Edition.
Urano, Hajime; Takizuka, Tomonori*; Kikuchi, Mitsuru; Nakano, Tomohide; Fujita, Takaaki; Oyama, Naoyuki; Kamada, Yutaka; Hayashi, Nobuhiko; JT-60 Team
Proceedings of 24th IAEA Fusion Energy Conference (FEC 2012) (CD-ROM), 8 Pages, 2013/01
Dependence of heat transport on isotopic composition is investigated in conventional H-mode plasmas for the application to ITER. The identical profiles of , and are obtained for hydrogen and deuterium plasmas while the required power becomes clearly larger for hydrogen, resulting in the reduction of the heat diffusivity for deuterium. The result of the identical temperature profiles in spite of different heating power suggests that the characteristics of heat conduction differs essentially between hydrogen and deuterium even at the same scale length of temperature gradient. On the other hand, the edge stability is improved by increased total regardless of the difference of the isotropic composition.
Kikuchi, Mitsuru; Azumi, Masafumi*
Reviews of Modern Physics, 84(4), p.1807 - 1854, 2012/12
Tokamak uses transformer action for plasma confinement. So, it is proposed to use non-inductive current drive including bootstrap current to achieve steady state operation. This paper reviews the progress of steady state tokamak research focused on theoretical aspect for 20 years since my proposal in 1990.
Urano, Hajime; Takizuka, Tomonori*; Kikuchi, Mitsuru; Nakano, Tomohide; Hayashi, Nobuhiko; Oyama, Naoyuki; Kamada, Yutaka
Physical Review Letters, 109(12), p.125001_1 - 125001_5, 2012/09
The dependence of the ion temperature gradient scale length on the hydrogen isotope mass was examined in conventional -mode plasmas in JT-60U tokamak. While identical profiles for density and temperature were obtained for hydrogen and deuterium plasmas, the ion conductive heat flux necessary for hydrogen to sustain the same thermal stored energy was two times that required for deuterium, resulting in a clearly higher ion heat diffusivity for hydrogen at the same ion temperature gradient scale length. The ion temperature gradient scale length for deuterium is less than that for hydrogen at a given ion heat diffusivity.
Honda, Mitsuru; Kikuchi, Mitsuru; Azumi, Masafumi*
Nuclear Fusion, 52(2), p.023021_1 - 023021_12, 2012/02
Ida, Katsumi*; Dong, J. Q.*; Kikuchi, Mitsuru; Kwon, J. M.*; Diamond, P. H.*
Nuclear Fusion, 52(2), p.027001_1 - 027001_10, 2012/02
This conference report summarizes the contributions to, and discussions at, the 1st Asia-Pacific Transport Working Group Meeting held in Toki, Japan, on 14-17 June 2011. The topics of the meeting were organized under four main headings: momentum transport, non-locality in transport, edge turbulence and L to H transition and 3D effects on transport physics. The events which initiated this meeting are also described in this report.
Urano, Hajime; Takizuka, Tomonori*; Kikuchi, Mitsuru; Nakano, Tomohide; Fujita, Takaaki; Hayashi, Nobuhiko; Oyama, Naoyuki; Kamada, Yutaka; JT-60 Team
Europhysics Conference Abstracts (Internet), 36F, p.P1.016_1 - P1.016_4, 2012/00
Energy confinement properties for hydrogen and deuterium H-mode plasmas were examined in JT-60U. The energy confinement time became larger by a factor of 1.2-1.3 for deuterium than for hydrogen at a given . When the plasma energy was fixed, the profiles of density and temperature became identical for both cases while higher heating power was required for hydrogen. The ion conductive heat flux for hydrogen became approximately two times that for deuterium. Hence, the ion heat diffusivity for hydrogen was higher than for deuterium. It was found that the ion-temperature-gradient scale length became smaller by a factor of 1.2 for deuterium than for hydrogen.
Kikuchi, Mitsuru; Lackner, K.*; Tran, M. Q.*
Fusion Physics, 1129 Pages, 2012/00
This bokk is 50 years anniversary textbook with 1200 pages on fusion physics published by IAEA. Representative phycisists all over the world contributed to this book. Chapter 1 : Prof. Kaw, Chapter 2: Prof. Goldston, Chapter 3: Prof. Lackner, Chapter 4: Dr. Zaveryaev, Chapter 5: Kikuchi, Okumura, Chapter 6: Prof. Porkolab, Chapter 7: Prof. Li, Chapter 8: Prof. Wagner, Chapter 9: Prof. Prager, Chapter 10: Prof. Mima
Asano, Shiro*; Okuyama, Toshihisa*; Onawa, Toshio*; Yanagi, Yutaka*; Ejiri, Mitsuru*; Kanahara, Toshio*; Ichihashi, Koji*; Kikuchi, Atsushi*; Mizumaki, Shoichi*; Masaki, Kei; et al.
Fusion Engineering and Design, 86(9-11), p.1816 - 1820, 2011/10
The real vacuum vessel (VV) manufacturing of JT-60SA has started since Nov. 2009 at Toshiba. Prior to starting manufacturing, fundamental welding R&Ds had been performed by three stages. In the first stage, primary tests for screening welding method were performed. In the second stage, the trial welding for 1m-long straight and curved double shell samples were conducted. The dependences of welding quality and distortion on the welding conditions, such as arc voltage and current, setting accuracy, welding sequence, the shape of grooves, etc. were measured. In addition, welding condition with low heat input was explored. In the last stage, fabrication sequence was confirmed and established by the trial manufacturing of the 20 upper half mock-up. This poster presents the R&D results obtained in the first and second stages.
Kikuchi, Mitsuru; Campbell, D. J.*
Fusion Science and Technology, 59(3), p.440 - 468, 2011/04
The ITER is an important step towards fusion energy utilization for human being. Fundamental understanding of physics is quite important as well as understanding of tokamak system and plasma control. In this lecture, I will give an introduction of tokamak research on fusion energy and ITER in light of the main theme of this school plasma control and give some flavors to understand importance of physics by showing some physics elements underlying research towards steady-state operation of reactor relevant tokamak plasmas.
Frontiers in Fusion Research; Physics and Fusion, 270 Pages, 2011/03
This book is intended to describe a systematic overview of the latest physical principles of fusion and plasma confinement. Students who learned the basics of quantum and analytical mechanics in university are introduced to the subject and may be interested in it as a future job option. Researchers in other fields may find commonalities and differences in the structure of the scientific principle of magnetic plasma confinement, which has been systematized through the 50 years of fusion research since its inception in 1958.
Proceedings of 6th IAEA Technical Meeting on Steady State Operations of Magnetic Fusion Devices (CD-ROM), 12 Pages, 2010/12
The steady state operation has been one of important research subjects in tokamak for more than 20 years. The major feature of efficient steady state operation of tokamak is the maximum utilization of the bootstrap current. Since bootstrap current fraction is proportional to poloidal beta, the reactor should operate in high toroidal beta regime. Scenarios needs wall stabilization with finite resistivity of the wall. The physics of toroidal rotation attracts more attention since even small toroidal rotation is important for stabilization of RWM. In this paper, structure of 1st order flow on the flux surface is revisited and the role of thermal flow qdT/dr on toroidal rotation is surveyed with respect to difference between bulk ion and impurity, and offset toroidal rotation due to non-axisymmetric field.
Energies (Internet), 3(11), p.1741 - 1789, 2010/11
As a memory of 50 years of fusion research, a review of fusion fundamentals, concept and research towards steady state tokamak reactor is reviewed. Since the development of SSTR concept in 1990, tokamak research made significant progresses as advanced tokamak research. Current formation and MHD stability in tokamak is reviewed.