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Furuya, Kazuyuki; Wakai, Eiichi; Miyamoto, Kenji*; Akiba, Masato; Sugimoto, Masayoshi
Journal of Nuclear Materials, 367-370(1), p.494 - 499, 2007/08
Times Cited Count：0 Percentile：0.00(Materials Science, Multidisciplinary)A partial mock-up of a breeding blanket structure made of F82H steel has been successfully fabricated. In this study, microstructural observation and EDX analysis of the HIP interfaces were performed, and effects of irradiation on mechanical properties of the HIP-bonded region were also examined. Neutron irradiation was performed up to about 2 dpa at about 523 K. After the irradiation, tensile test was performed at temperatures of 295 and 523 K. The HIP interfaces possessed many precipitates, and enriched peak spectrum of chromium was detected from the precipitates. In addition, aspect of the spectrum was qualitatively equivalent to that of M
C
in grain boundaries of F82H steel. In result, the HIP boundary has many MC which were generally seen in grain boundaries of F82H steel. Rupture did not occur in the HIP interface. In result, it can be mentioned that bondability is maintained under the irradiation and testing conditions. The strength and elongation of the HIP-bonded region decreased somewhat in comparison with the results of an IEA standard steel.
Yamada, Hirokazu*; Kawamura, Hiroshi; Nagao, Yoshiharu; Takada, Fumiki; Kono, Wataru*
Journal of Nuclear Materials, 355(1-3), p.119 - 123, 2006/09
Times Cited Count：5 Percentile：35.34(Materials Science, Multidisciplinary)In this study, the bending properties of welding joint of irradiated material and un-irradiated material (irradiated/un-irradiated joints) were investigated using SS316LN-IG, which is the candidate material for the cooling pipe of ITER. The results of this study showed that the bending position of joints using un-irradiated material was un-irradiated part and that the bending position of irradiated/irradiated joints was fusion area or HAZ (heat affected zone). Although the bending position of joints was different bor the combination pattern between irradiated and un-irradiated materials, the bending strength of joint was almost same. Additionally, it is confirmed that bending strength did not depend on the combination pattern between the irradiated and un-irradiated materials, nor on the relationship between the heat input direction and the bending load direction.
Takahashi, Koji; Illy, S.*; Heidinger, R.*; Kasugai, Atsushi; Minami, Ryutaro; Sakamoto, Keishi; Thumm, M.*; Imai, Tsuyoshi
Fusion Engineering and Design, 74(1-4), p.305 - 310, 2005/11
Times Cited Count：14 Percentile：66.47(Nuclear Science & Technology)A new diamond window with the copper-coated edge for an EC launcher is developed. The diamond window is designed to cool its disk edge. Since Cu is coated at the entire edge, ingress of cooling water into a transmission line in case of failure on the edge is negligible. In addition, corrosion of Al blaze between the edge and the Inconel cuffs can be avoided. A 170GHz, RF transmission experiment equivalent to a MW-level transmission was carried out to investigate the capability of the edge cooling. The transmission power and pulse are 55kW and 3sec, respectively. Temperature increase was 45
C and alomost became constant. Thermal calculation with tan
of 4.4
10
and thermal conductivity of 1.9kW/m/K agrees with the experiment. Since tan of the diamond is much higher than the actual one (tan=210
), the temperature increase corresponds to that of 1MW transmission. It concludes that the Cu coating dose not degrade the edge cooling capability and improves the reliability of the diamond window.
TiO
pebbles from Li-Ti complex solutionTsuchiya, Kunihiko; Kawamura, Hiroshi; Casadio, S.*; Alvani, C.*
Fusion Engineering and Design, 75-79, p.877 - 880, 2005/11
Times Cited Count：27 Percentile：84.12(Nuclear Science & Technology)no abstracts in English
TiO under varied surface conditionOlivares, R.*; Oda, Takuji*; Oya, Yasuhisa*; Tanaka, Satoru*; Tsuchiya, Kunihiko
Fusion Engineering and Design, 75-79, p.765 - 768, 2005/11
Times Cited Count：9 Percentile：51.72(Nuclear Science & Technology)no abstracts in English
Seki, Masami; Moriyama, Shinichi; Shinozaki, Shinichi; Hasegawa, Koichi; Hiranai, Shinichi; Yokokura, Kenji; Shimono, Mitsugu; Terakado, Masayuki; Fujii, Tsuneyuki
Fusion Engineering and Design, 74(1-4), p.273 - 277, 2005/11
Times Cited Count：3 Percentile：23.49(Nuclear Science & Technology)no abstracts in English
Kondo, Hiroo*; Fujisato, Atsushi*; Yamaoka, Nobuo*; Inoue, Shoji*; Miyamoto, Seiji*; Iida, Toshiyuki*; Nakamura, Hiroo; Ida, Mizuho*; Matsushita, Izuru*; Muroga, Takeo*; et al.
Fusion Engineering and Design, 75-79, p.865 - 869, 2005/11
Times Cited Count：22 Percentile：79.24(Nuclear Science & Technology)no abstracts in English
Maebara, Sunao; Moriyama, Shinichi; Saigusa, Mikio*; Sugimoto, Masayoshi; Imai, Tsuyoshi; Takeuchi, Hiroshi
Fusion Engineering and Design, 75-79, p.823 - 827, 2005/11
Times Cited Count：2 Percentile：17.10(Nuclear Science & Technology)An RF-Input coupler with a multi-loop antenna using co-axial waveguides has been developed for the RFQ linac on IFMIF. In case of using a loop antenna, the loop antenna structure will affected phase difference and power balance in each cavity. A mock-up loop antenna using the pipe diameter of 10mm was fabricated, phase differences and power balances were measured by a low power test. It is found that it is necessary to shorten the installed depth up to 3 cm to make the phase differences and power balance small. But, from a withstanding voltage, it is difficult to couple multi-MW with the single coupler. The coupling with multi-loop antennas using two or four loops is better than one loop antenna from the point views of both withstanding voltage and power balance. The phase difference and power balance were also measured in both cases. A good average phase-difference of 179. and a good RF power balance within 8% error for each cavity were obtained. These results showed one of feasibility for an RF-Input coupler with a multi-loop antenna in the IFMIF 175 MHz RFQ.
Nakamura, Hiroo; Takemura, Morio*; Yamauchi, Michinori*; Fischer, U.*; Ida, Mizuho*; Mori, Seiji*; Nishitani, Takeo; Simakov, S.*; Sugimoto, Masayoshi
Fusion Engineering and Design, 75-79, p.1169 - 1172, 2005/11
Times Cited Count：6 Percentile：39.52(Nuclear Science & Technology)In the IFMIF, activated erosion/corrosion materials of Li target back wall deposits on a surface of the Li loop. Therefore, accessibility during maintenance of the Li loop pipings will depend on the activation level of the deposition materials. This paper evaluates effect of target activation on the accessibility of the Li loop pipings. Activation level is calculated by the ACT-4 code. High energy cross section above 15 MeV is introduced using IEAF-2001 data. In this calculation, target material is stainless steel 316. Area of the erosion/corrosion in the back wall is 100 cm
. The erosion/corrosion rate is 1 micron/y. Dose rate around the Li loop after one year IFMIF operation is evaluated assuming 1% deposition of the erosion/corrosion materials and uniform deposition on surface area of 33 m. Permissible level for hands-on maintenance is 10 microSv/hr. As the results, after 1 week from shutdown, close maintenance work 8 cm to the Li loop is possible. Also, after 1 month, hands-on maintenance becomes possible.
Ioki, Kimihiro*; Elio, F.*; Maruyama, So; Morimoto, Masaaki*; Rozov, V.*; Tivey, R.*; Utin, Y.*
Fusion Engineering and Design, 74(1-4), p.185 - 190, 2005/11
Times Cited Count：5 Percentile：34.88(Nuclear Science & Technology)The ITER project has started preparation of Procurement Specification Documents for the vacuum vessel (VV). The design of the VV and FW/Blanket has progressed in many aspects, such as an double curvature pressing instead of facet shape welding for inner and outer shells in the upper and lower inboard regions to improve the fabrication and NDT process. The plasma facing surface of the FW has been defined to avoid protruding the leading edges, especially in the inboard area. Separate FW panels are supported with a central beam, and selection of a race-track shape cross-section for the central beam provides a more robust structure against halo current EM loads and also leads to a new cooling configuration in the shield block, where the pressure drop is significantly reduced to 
0.05 MPa. A UT R&D program is also going on to achieve acceptable S/N ratio for small-angle launching waves (20-30 deg.) to a weld. Hydraulic testing has been performed to demonstrate natural convection cooling in the transient condition.
test results of a D-shaped NbAl CICC coil fabricated with a react-and-wind process for the National Centralized TokamakAndo, Toshinari*; Kizu, Kaname; Miura, Yushi*; Tsuchiya, Katsuhiko; Matsukawa, Makoto; Tamai, Hiroshi; Ishida, Shinichi; Koizumi, Norikiyo; Okuno, Kiyoshi
Fusion Engineering and Design, 75-79, p.99 - 103, 2005/11
Times Cited Count：1 Percentile：10.17(Nuclear Science & Technology)no abstracts in English
Yoshida, Kiyoshi; Takahashi, Yoshikazu; Isono, Takaaki; Mitchell, N.*
Fusion Engineering and Design, 75-79, p.241 - 247, 2005/11
Times Cited Count：10 Percentile：55.51(Nuclear Science & Technology)The ITER superconducting magnet system stores energy of 50 GJ during plasma operation, and generates an average heat load of 23 kW at 4 K to cryoplant. The helium is distributed to the coil through 30 separate feeder lines. The feeders also contain the electrical supplies to the coil and are integrated into the current lead transition to room temperature. The interface components between the coils and the service facilities (power supply and cryogenic plant) consist of the in-cryostat feeders, the cryostat feedthroughs, and the coil terminal boxes (CTBs). The cryostat feedthroughs with S-bend boxes allow thermal contraction of the magnet system. The layout of the in-cryostat feeders takes into consideration routing restrictions in the cryostat and initial assembly with other Tokamak components. The forced-flow-cooled current leads with a conventional copper heat exchanger in the CTBs are adapted to fit in the limited space in the building. This paper presents the latest design concept and parameters of the feeder components.
TiO under hydrogen atmosphere conditionHoshino, Tsuyoshi; Tsuchiya, Kunihiko; Hayashi, Kimio; Terai, Takayuki*; Tanaka, Satoru*; Takahashi, Yoichi*
Fusion Engineering and Design, 75-79, p.939 - 943, 2005/11
Times Cited Count：13 Percentile：64.19(Nuclear Science & Technology)no abstracts in English
Shimomura, Yasuo
Fusion Engineering and Design, 74(1-4), p.9 - 16, 2005/11
Times Cited Count：22 Percentile：79.24(Nuclear Science & Technology)no abstracts in English
Kurihara, Kenichi; Kawamata, Yoichi; Sueoka, Michiharu; Hosoyama, Hiroki*; Yonekawa, Izuru; Suzuki, Takahiro; Oikawa, Toshihiro; Ide, Shunsuke; JT-60 Team
Fusion Engineering and Design, 74(1-4), p.527 - 536, 2005/11
Times Cited Count：15 Percentile：66.47(Nuclear Science & Technology)Since tokamak magnetic fusion research has just made a step forward to an international collaborative project ITER, the existing tokamaks including JT-60 are expected to explore more advanced operation scenarios. To test those scenarios in the JT-60 experiment, the basic methods for understanding of plasma equilibrium have been developed. Some of them have been accomplished, and the other are being conducted as follows: (1) A complete plasma shape is precisely reproduced in real time. (2) Eddy current effects are considered for shape reproduction. (3) A plasma current profile in the poloidal cross-section is reproduced in real. (4) For long-pulse DT operation, a method is developed to correct the drifted signal of the integrator for a pick-up coil by employing distant sensor signals. In the symposium, those methods will be explained in detail with the experimental results at JT-60. On the basis of such discussion, we would like to envisage a future of plasma equilibrium control toward ITER and a fusion power plant.
Ochiai, Kentaro; Kondo, Keitaro; Murata, Isao*; Miyamaru, Hiroyuki*; Kubota, Naoyoshi; Takahashi, Akito*; Nishitani, Takeo
Fusion Engineering and Design, 75-79, p.859 - 863, 2005/11
Times Cited Count：0 Percentile：0.00(Nuclear Science & Technology)The Fusion Neutronics Source (FNS) of JAERI currently carries out the measurements of energetic charged particles emitted from fusion materials irradiated with a well-collimated 14 MeV neutron beam. At the beginning, the double differential cross section beryllium was measured. We have measured proton, triton and a particle emitted from a beryllium sample of 100 
m in thickness.The a particle and triton were produced by 
Be(n,
)
He, Be(n,2n)2 and Be(n,t)
Li reactions respectively. Measured total reaction rates from the counts of a particles and tritons were 2.710
and 610
/atom/neutron, respectively, which were consistent with the calculated values from the nuclear data JENDL-3.2.
Ezato, Koichiro; Suzuki, Satoshi; Dairaku, Masayuki; Akiba, Masato
Fusion Engineering and Design, 75-79, p.313 - 318, 2005/11
Times Cited Count：10 Percentile：55.51(Nuclear Science & Technology)no abstracts in English
Umeda, Naotaka; Yamamoto, Takumi; Hanada, Masaya; Grisham, L. R.*; Kawai, Mikito; Oga, Tokumichi; Akino, Noboru; Inoue, Takashi; Kazawa, Minoru; Kikuchi, Katsumi*; et al.
Fusion Engineering and Design, 74(1-4), p.385 - 390, 2005/11
Times Cited Count：9 Percentile：51.72(Nuclear Science & Technology)In negative ion based neutral beam injector (N-NBI) for JT-60U, some modifications for extent pulse duration from 10 second, which is design value, to 30 second was conducted. Main limit to prevent pulse extension was heat loads onto grounded grid in an ion source and onto beam limiter placed at 22 m from the ion source. To reduce these heat loads, beam extraction area was optimized and the limiter was changed to one which had about twice thermal capacity. As a result of these modifications, the temperature rise of the water which was cooling grounded grid could be suppressed under 40 degree, which can operate in steady state condition. The temperature rise of the limiter could be restricted to 60%. Untill now the beam pulse extended to 17 second of 1.6MW power at 366keV energy, and injection of 30 seconds will be achieved in next experiment.
Oya, Yasuhisa*; Hirohata, Yuko*; Tanabe, Tetsuo*; Shibahara, Takahiro*; Kimura, Hiromi*; Oyaizu, Makoto*; Arai, Takashi; Masaki, Kei; Goto, Yoshitaka*; Okuno, Kenji*; et al.
Fusion Engineering and Design, 75-79, p.945 - 949, 2005/11
Times Cited Count：9 Percentile：51.72(Nuclear Science & Technology)no abstracts in English
Iida, Hiromasa; Petrizzi, L.*; Khripunov, V.*; Federici, G.*; Polunovskiy, E.*
Fusion Engineering and Design, 75(1-4), p.133 - 139, 2005/11
The design of the ITER machine was presented in 2001. A nuclear analysis has been performed on ITER by means of the most detailed models and the best assessed nuclear data and codes. As the construction phase of ITER is approaching, the design of the main components has been optimized/finalized and several minor design changes/optimizations have been made, which required refined calculations to confirm that nuclear design requirements are met. Some of the proposed design changes have been made to mitigate critical radiation shielding problems. This paper reviews some of the most recent neutronic work with emphasis on critical nuclear responses in the TF coil inboard legs and vacuum vessel related to design modifications made to the blanket modules and vacuum vessel.
