R&D status on water cooled ceramic breeder blanket technology

Enoeda, Mikio; Tanigawa, Hisashi; Hirose, Takanori; Nakajima, Motoki; Sato, Satoshi; Ochiai, Kentaro; Konno, Chikara; Kawamura, Yoshinori; Hayashi, Takumi; Yamanishi, Toshihiko; et al.

Fusion Engineering and Design, 89(7-8), p.1131 - 1136, 2014/10

https://doi.org/10.1016/j.fusengdes.2014.01.035

The development of a Water Cooled Ceramic Breeder (WCCB) Test Blanket Module (TBM) is being performed as one of the most important steps toward DEMO blanket in Japan. Regarding the fabrication technology development using F82H, the fabrication of a real scale mockup of the back wall of TBM was completed. Also the assembling of the complete box structure of the TBM mockup and planning of the pressurization testing was studied. The development of advanced breeder and multiplier pebbles for higher chemical stability was performed for future DEMO blanket application. From the view point of TBM test result evaluation and DEMO blanket performance design, the development of the blanket tritium simulation technology, investigation of the TBM neutronics measurement technology and the evaluation of tritium production and recovery test using D-T neutron in the Fusion Neutronics Source (FNS) facility has been performed.

Precise measurement of superconducting cavity movement in cryomodule by the position monitor using white light interferometer

Sakai, Hiroshi*; Aoto, Tomohiro*; Enami, Kazuhiro*; Furuya, Takaaki*; Sato, Masato*; Shinoe, Kenji*; Umemori, Kensei*; Sawamura, Masaru; Cenni, E.*; Hayashi, Kyohei*; et al.

Proceedings of 16th International Conference on RF Superconductivity (SRF 2013) (Internet), p.291 - 296, 2014/02

http://accelconf.web.cern.ch/AccelConf/SRF2013/papers/mop069.pdf

Alignment of superconducting cavities is one of the important issues for linear collider and/or future light source like ERL and X-FEL. To measure the cavity displacement under cooling to liquid He temperature more precisely, we newly developed the position monitor by using white light interferometer. This monitor is based on the measurement of the interference of light between the measurement target and the reference point. It can measure the position from the outside of the cryomodule. We applied this monitor to the main linac cryomodule of Compact ERL (cERL) and successfully measured the displacement during 2 K cooling with the resolution of 10 m.

Effect of sweep gas species on tritium release behavior from lithium titanate packed bed during 14MeV neutron irradiation

Kawamura, Yoshinori; Ochiai, Kentaro; Hoshino, Tsuyoshi; Kondo, Keitaro*; Iwai, Yasunori; Kobayashi, Kazuhiro; Nakamichi, Masaru; Konno, Chikara; Yamanishi, Toshihiko; Hayashi, Takumi; et al.

Fusion Engineering and Design, 87(7-8), p.1253 - 1257, 2012/08

https://doi.org/10.1016/j.fusengdes.2012.02.125

Tritium generation and recovery study on lithium ceramic packed bed was started by use of FNS in JAEA. Lithium titanate was selected as tritium breeding material. In this work, the effect of sweep gas species on tritium release behavior was investigated. In case of sweep by helium with 1% of hydrogen, tritium in water form was released sensitively corresponding to the irradiation. This is due to existence of the water vapor in the sweep gas. On the other hand, in case of sweep by dry helium, tritium in gaseous form was released first, and release of tritium in water form was delayed and was gradually increased.

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.

International Fusion Energy Research Centre

Araki, Masanori; Hayashi, Kimio; Tobita, Kenji; Nishitani, Takeo; Tanigawa, Hiroyasu; Nozawa, Takashi; Yamanishi, Toshihiko; Nakamichi, Masaru; Hoshino, Tsuyoshi; Ozeki, Takahisa; et al.

Purazuma, Kaku Yugo Gakkai-Shi, 86(4), p.231 - 239, 2010/04

http://ci.nii.ac.jp/naid/110007610367

The Broader Approach Activities, which support the ITER Project and implement activities to aim early realization of fusion energy, is an EU-Japan collaborative project to carry out various kinds of researches and developments during the period of the ITER construction phase. In this special topic, achievements and prospects of the projects on the International Fusion Energy Research Centre (IFERC) is described.

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).

Impact of ceramic coating deposition on the tritium permeation in the Japanese ITER-TBM

Nakamichi, Masaru; Nakamura, Hirofumi; Hayashi, Kimio; Takagi, Ikuji*

Journal of Nuclear Materials, 386-388, p.692 - 695, 2009/04

https://doi.org/10.1016/j.jnucmat.2008.12.282

no abstracts in English

Deuterium diffusion in a chemical densified coating observed by NRA

Takagi, Ikuji*; Kobayashi, Takashi*; Ueyama, Yutaka*; Moriyama, Hirotake*; Nakamichi, Masaru; Nakamura, Hirofumi; Hayashi, Kimio

Journal of Nuclear Materials, 386-388, p.682 - 684, 2009/04

https://doi.org/10.1016/j.jnucmat.2008.12.275

no abstracts in English

Study of waste acceptance criteria for low-level radioactive waste from medical, industrial, and research facilities (Contract research)

Koibuchi, Hiroto; Dohi, Terumi; Ishiguro, Hideharu*; Hayashi, Masaru*; Senda, Masaki*

JAEA-Review 2008-034, 59 Pages, 2008/12

JAEA-Review-2008-034.pdf:10.61MB

Japan Atomic Energy Agency (JAEA) is supposed to draw up the plan for the disposal program of the very low-level radioactive waste and low-level radioactive waste generated from medical, industrial and research facilities. For instance, there are these facilities in JAEA, universities, private companies, and so on. JAEA has to get to know about the waste and its acceptance of other institutions described above because it is important for us to hold the licenses for the disposal program regarding safety assessment. This report presents the basic data concerning radioactive waste of research institutes etc. except RI waste, domestic and foreign information related to acceptance criteria for disposal of the low-level radioactive waste, the current status of foreign medical waste management, waste acceptance, and such. In this report, Japan's acceptance criteria were summarized on the basis of present regulation. And, the criteria of foreign countries, United States, France, United Kingdom and Spain, were investigated by survey of each reference. In addition, it was reported that the amount of waste from laboratories etc. for near-surface disposal and their characterization in our country. The Subjects of future work, the treatment of hazardous waste, the problem of the double-regulation (the Nuclear Reactor Regulation Law and the Law Concerning Prevention from Radiation Hazards due to Radioisotopes and Others) and the possession of waste were discussed here.

Novel anisotropic superconductivity in nano-structured superconductors

Kato, Masaru*; Koyama, Tomio*; Machida, Masahiko; Hayashi, Masahiko*; Ebisawa, Hiromichi*; Ishida, Takekazu*

Physica B; Condensed Matter, 403(5-9), p.996 - 998, 2008/04

https://doi.org/10.1016/j.physb.2007.10.275

Using the Bogoliubov-de Gennes equation of a tight-binding electron model with attractive on-site and nearest-neighbor sites interactions, we investigate the superconducting structure of nano-structured anisotropic superconductors. Numerical results show that nano-scaled /4-rotated square d-wave superconductors show various type of uperconductivities depending on the size. Especially, + superconductivity, appears when size of superconductors is 10 times of coherence length.