Plan of ITER Remote Experimentation Center

Ozeki, Takahisa; Clement, L. S.*; Nakajima, Noriyoshi*

Fusion Engineering and Design, 89(5), p.529 - 531, 2014/05

https://doi.org/10.1016/j.fusengdes.2014.04.075

no abstracts in English

Integrated simulation of ELM triggered by a pellet through energy absorption and transport enhancement

Hayashi, Nobuhiko; Parail, V.*; Koechl, F.*; Aiba, Nobuyuki; Takizuka, Tomonori; Wiesen, S.*; Lang, P. T.*; Oyama, Naoyuki; Ozeki, Takahisa

Nuclear Fusion, 51(10), p.103030_1 - 103030_8, 2011/10

https://doi.org/10.1088/0029-5515/51/10/103030

Effect of core pressure gradient just inside the top of the pedestal on the energy loss due to the edge localized mode in JT-60U

Hayashi, Nobuhiko; Oyama, Naoyuki; Takizuka, Tomonori; Aiba, Nobuyuki; Ozeki, Takahisa

Nuclear Fusion, 51(7), p.073015_1 - 073015_7, 2011/07

https://doi.org/10.1088/0029-5515/51/7/073015

Alpha particle-driven toroidal rotation in burning plasmas

Honda, Mitsuru; Takizuka, Tomonori; Tobita, Kenji; Matsunaga, Go; Fukuyama, Atsushi*; Ozeki, Takahisa

Proceedings of 23rd IAEA Fusion Energy Conference (FEC 2010) (CD-ROM), 8 Pages, 2011/03

http://www-naweb.iaea.org/napc/physics/FEC/FEC2010/html/node328.htm#68899

Conceptual design of the SlimCS fusion DEMO reactor

Tobita, Kenji; Nishio, Satoshi*; Enoeda, Mikio; Nakamura, Hirofumi; Hayashi, Takumi; Asakura, Nobuyuki; Uto, Hiroyasu; Tanigawa, Hiroyasu; Nishitani, Takeo; Isono, Takaaki; et al.

JAEA-Research 2010-019, 194 Pages, 2010/08

JAEA-Research-2010-019-01.pdf:48.47MB
JAEA-Research-2010-019-02.pdf:19.4MB

This report describes the results of the conceptual design study of the SlimCS fusion DEMO reactor aiming at demonstrating fusion power production in a plant scale and allowing to assess the economic prospects of a fusion power plant. The design study has focused on a compact and low aspect ratio tokamak reactor concept with a reduced-sized central solenoid, which is novel compared with previous tokamak reactor concept such as SSTR (Steady State Tokamak Reactor). The reactor has the main parameters of a major radius of 5.5 m, aspect ratio of 2.6, elongation of 2.0, normalized beta of 4.3, fusion out put of 2.95 GW and average neutron wall load of 3 MW/m. This report covers various aspects of design study including systemic design, physics design, torus configuration, blanket, superconducting magnet, maintenance and building, which were carried out increase the engineering feasibility of the concept.

Rotational stabilization of resistive wall mode on JT-60U

Matsunaga, Go; Takechi, Manabu; Aiba, Nobuyuki; Kurita, Genichi; Sakamoto, Yoshiteru; Koide, Yoshihiko; Isayama, Akihiko; Suzuki, Takahiro; Fujita, Takaaki; Oyama, Naoyuki; et al.

Plasma and Fusion Research (Internet), 4, p.051_1 - 051_7, 2009/11

https://doi.org/10.1585/pfr.4.051

no abstracts in English

Integrated modeling for control of advanced tokamak plasma

Ozeki, Takahisa; Hayashi, Nobuhiko; Honda, Mitsuru; Aiba, Nobuyuki; Hamamatsu, Kiyotaka; Shimizu, Katsuhiro; Kawashima, Hisato; Hoshino, Kazuo; Takizuka, Tomonori; Tokuda, Shinji

Journal of Plasma and Fusion Research SERIES, Vol.8, p.1138 - 1142, 2009/09

Compact DEMO, SlimCS; Design progress and issues

Tobita, Kenji; Nishio, Satoshi; Enoeda, Mikio; Kawashima, Hisato; Kurita, Genichi; Tanigawa, Hiroyasu; Nakamura, Hirofumi; Honda, Mitsuru; Saito, Ai*; Sato, Satoshi; et al.

Nuclear Fusion, 49(7), p.075029_1 - 075029_10, 2009/07

https://doi.org/10.1088/0029-5515/49/7/075029

Recent design study on SlimCS focused mainly on the torus configuration including blanket, divertor, materials and maintenance scheme. For vertical stability of elongated plasma and high beta access, a sector-wide conducting shell is arranged in between replaceable and permanent blanket. The reactor adopts pressurized-water-cooled solid breeding blanket. Compared with the previous advanced concept with supercritical water, the design options satisfying tritium self-sufficiency are relatively scarce. Considered divertor technology and materials, an allowable heat load to the divertor plate should be 8 MW/m or lower, which can be a critical constraint for determining a handling power of DEMO (a combination of alpha heating power and external input power for current drive).

Effects of a sheared toroidal rotation on the stability boundary of the MHD modes in the tokamak edge pedestal

Aiba, Nobuyuki; Tokuda, Shinji; Furukawa, Masaru*; Oyama, Naoyuki; Ozeki, Takahisa

Nuclear Fusion, 49(6), p.065015_1 - 065015_9, 2009/06

https://doi.org/10.1088/0029-5515/49/6/065015

Effects of a toroidal rotation are investigated numerically on the stability of the MHD modes in the tokamak edge pedestal, which relate to the type-I edge-localized mode (ELM). A linear MHD stability code MINERVA is newly developed for solving the Frieman-Rotenberg equation that is the linear ideal MHD equation with flow. Numerical stability analyses with this code reveal that the sheared toroidal rotation destabilizes edge localized MHD modes, and this rotation effect becomes stronger as the toroidal mode number of the unstable MHD mode increases in case that the toroidal mode number is smaller than 40. Since the toroidal mode number of the unstable MHD mode strongly depends on the safety factor profile, the destabilizing effect of the toroidal rotation is affected by the safety factor profile. The sheared toroidal rotation also has an impact on the mode structure of the edge localized MHD mode, and the mode structure can become narrower as the toroidal rotation increases.

Self-consistent simulation of torque generation by radial current due to fast particles

Honda, Mitsuru; Takizuka, Tomonori; Fukuyama, Atsushi*; Yoshida, Maiko; Ozeki, Takahisa

Nuclear Fusion, 49(3), p.035009_1 - 035009_10, 2009/03

https://doi.org/10.1088/0029-5515/49/3/035009

The generation of the toroidal rotation due to the radial current torque induced by the charge separation is studied by using one-dimensional multi-fluid transport code TASK/TX. Owing to the effect of the drift motion, the charge separation occurs as long as trapped ions are generated, typically by near-perpendicular NBI. Coupling the TASK/TX code with the OFMC code, we have reproduced that the toroidal rotation is driven due to the generation of the radial current by the near-perpendicular NBI. The simulations has clarified that the NB on the equatorial plane drives the toroidal rotation most efficiently from the aspects of the collisional and torques. The torque becomes a major driver of the rotation in a high density plasma. In a steady state, the toroidal rotation is determined by the balance among the torque, the viscosity, the friction with neutrals and the loss of momentum due to charge exchange.