Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Shiba, Kiyoyuki; Tanigawa, Hiroyasu; Hirose, Takanori; Sakasegawa, Hideo; Jitsukawa, Shiro
Fusion Engineering and Design, 86(12), p.2895 - 2899, 2011/12
Times Cited Count：45 Percentile：94.12(Nuclear Science & Technology)Aging properties of reduced activation ferritic/martensitic steel F82H was researched at temperature ranging from 400
C to 650C up to 100,000 hr. Microstructure, tensile, and Charpy properties were carried out. Laves was found at temperatures between 550 and 650C and M
C carbides were found at the temperatures between 500 and 600C over 10,000 hr. These precipitates caused degradation in toughness, especially at temperatures ranging from 550C to 650C. Tensile properties do not have serious aging effect, except for 650C, which caused large softening even after 10.000 hr. Increase of precipitates also causes some degradation in ductility, but it is not critical. Large increase in DBTT caused by the large Laves phase precipitation at grain boundary was observed in the 650C aging. Laves precipitates at grain boundary also degrades the USE of the aged materials. These aging test results provide F82H can be used up to 30,000 hr at 550C.
Kogawara, Takafumi; Wakai, Eiichi; Kikuchi, Takayuki; Yamamoto, Michiyoshi; Molla, J.*
Fusion Engineering and Design, 86(12), p.2904 - 2907, 2011/12
Times Cited Count：3 Percentile：24.79(Nuclear Science & Technology)no abstracts in English
Chida, Yutaka; Iguchi, Masahide; Takano, Katsutoshi; Nakajima, Hideo; Osemochi, Koichi*; Niimi, Kenichiro*; Tokai, Daisuke*; Gallix, R.*
Fusion Engineering and Design, 86(12), p.2900 - 2903, 2011/12
Times Cited Count：10 Percentile：58.64(Nuclear Science & Technology)TF coil structures, which support large electromagnetic force generated in TF coils under the cryogenic temperature (about 4K), are the mega welding structures composed of coil case and support structures made of high strength and high toughness stainless steel. JAEA started the study on welding trials for heavy thickness materials since 2008 and is planning of full scale mock-up model fabrication for main sub-components (1 set of inboard side and 1set of outboard side) in 2010 in order to investigate the technical issues for manufacturing of TF coil structures. This paper introduces the results on welding trials and status of full scale mock-up model fabrication to confirm the validity of welding technology and manufacturing design before fabricating actual products.
Nishitani, Takeo; Yamanishi, Toshihiko; Tanigawa, Hiroyasu; Nozawa, Takashi; Nakamichi, Masaru; Hoshino, Tsuyoshi; Koyama, Akira*; Kimura, Akihiko*; Hinoki, Tatsuya*; Shikama, Tatsuo*
Fusion Engineering and Design, 86(12), p.2924 - 2927, 2011/12
Times Cited Count：7 Percentile：46.79(Nuclear Science & Technology)Several technical R&D activities related to the blanket materials are newly launched as a part of the Broader Approach (BA) activities, which was initiated by the EU and Japan. According to the common interests of these parties for DEMO, R&Ds on reduced activation ferritic/martensitic (RAFM) steels as structural material, SiCf/SiC composites as a flow channel insert material and/or alternative structural material, advanced tritium breeders and neutron multipliers, and tritium technology are carried out through the BA DEMO R&D program, in order to establish the technical bases on the blanket materials and the tritium technology required for DEMO design. This paper describes overall schedule of those R&D activities and recent progress in Japan carried out by JAEA as the domestic implementing agency on BA, collaborating with Japanese universities and other research institutes.
Someya, Yoji; Takase, Haruhiko; Uto, Hiroyasu; Tobita, Kenji; Liu, C.; Asakura, Nobuyuki
Fusion Engineering and Design, 86(9-11), p.2269 - 2272, 2011/11
Times Cited Count：37 Percentile：91.94(Nuclear Science & Technology)Conceptual design of a tritium-breeding blanket for SlimCS has been studied. The blanket structure with neutron multiplier Be-plate was designed to be as thin as possible with keeping high Tritium Breeding Ratio (TBR). However, a structure of the blanket is complexity and the manufacture of the blanket is difficult from the viewpoint of engineering. Therefore, simplification of blanket structure is necessary for SlimCS. In this paper, we propose a simple blanket structure without decreasing the net TBR below 1.05. The proposed blanket structure is mixed Li
SiO pebbles or Li
O pebbles for the tritium breeding and Be
Ti pebbles for the neutron multiplication and these pebbles are filled in the blanket. ANIHEAT code with the nuclear data library FENDL-2.0 was used for the calculations of the neutronics and thermal analyses. As a result, it is shown that LiO pebbles blanket mixed with BeTi pebbles is the most effective and the TBR is greater than 1.05.
Coletti, A.*; Baulaigue, O.*; Cara, P.*; Coletti, R.*; Ferro, A.*; Gaio, E.*; Matsukawa, Makoto; Novello, L.*; Santinelli, M.*; Shimada, Katsuhiro; et al.
Fusion Engineering and Design, 86(6-8), p.1373 - 1376, 2011/10
Times Cited Count：24 Percentile：84.20(Nuclear Science & Technology)Kizu, Kaname; Kashiwa, Yoshitoshi; Murakami, Haruyuki; Obana, Tetsuhiro*; Takahata, Kazuya*; Tsuchiya, Katsuhiko; Yoshida, Kiyoshi; Hamaguchi, Shinji*; Matsui, Kunihiro; Nakamura, Kazuya*; et al.
Fusion Engineering and Design, 86(6-8), p.1432 - 1435, 2011/10
Times Cited Count：8 Percentile：51.42(Nuclear Science & Technology)In JT-60SA, central solenoid (CS) and plasma equilibrium field (EF) coils are procured by Japan. EF coil conductors are NbTi cable-in-conduit (CIC) conductor. Delivered superconducting cables and jackets are fabricated into CIC conductors at the jacketing facility with the length of 680 m constructed in the Naka site of JAEA. The production of superconductors with 444 m in length for actual EF coils was started from March 2010. The measurements of superconducting performance like current sharing temperature (Tcs) were conducted prior to the mass production. The measured Tcs was agreed with the expectation values from strand values indicating that no degradation was happened by production process.
Hamada, Kazuya; Takahashi, Yoshikazu; Isono, Takaaki; Nunoya, Yoshihiko; Matsui, Kunihiro; Kawano, Katsumi; Oshikiri, Masayuki; Tsutsumi, Fumiaki; Koizumi, Norikiyo; Nakajima, Hideo; et al.
Fusion Engineering and Design, 86(6-8), p.1506 - 1510, 2011/10
Times Cited Count：12 Percentile：64.74(Nuclear Science & Technology)Japan Atomic Energy Agency has a responsibility for procurement of the ITER toroidal field coil conductors as Japanese Domestic Agency (JADA) of the ITER project. The TF conductor is a circular shaped cable-in-conduit conductor, which is composed of cable and stainless steel conduit (jacket). The outer diameter and wall thickness of jacket are 43.7mm and 2mm, respectively. The cable consists of 900 Nb
Sn superconducting strands and 522 Cu strands. The length of TF conductor is 780m in maximum. Preparation of conductor fabrication was completed in December 2009. And then, to demonstrate a conductor manufacturing procedure, JADA fabricated 780m-long Cu dummy conductor as a process qualification. Finally, the 780m-long Cu dummy conductor has been successfully completed, ahead of other domestic agencies that are in charge of TF conductor procurement. Since all of manufacturing processes have been qualified, JADA started to fabricate superconducting conductors for TF coils.
Kwak, J. G.*; Wang, S. J.*; Bae, Y. D.*; Kim, S. H.*; Hwang, C. K.*; Moriyama, Shinichi
Fusion Engineering and Design, 86(6-8), p.938 - 941, 2011/10
Times Cited Count：1 Percentile：10.30(Nuclear Science & Technology)KAERI have been developing the transmitters for ICRF heating for KSTAR and the cyclotron accelerator since 1996. The toroidal magnetic field of KSTAR is nominally 3 T so that 25-60 MHz transmitter is required to cover ICRF heating scenarios of the KSTAR. The first transmitter is operating up to 60 MHz and it succeeded in achieving 2 MW for 300 s in 2008. Up to 300 kW RF power was successfully injected to KSTAR plasmas. The second one is 70 kW/CW transmitter used for the cyclotron accelerator and their frequency range is from 25 to 50 MHz. Its engineering design was finished. The third one is 1 MW/VHF transmitter which was loaned from JAEA. As the operating ICRF frequency of KSTAR is lower, its cavity structure will be modified from 110 MHz to 60 MHz. The test results of 60 MHz and lessons from the high power test of 2 MW transmitter will be introduced and the circuit analysis and engineering design work for the second and third amplifiers will be shown.
Kobayashi, Takayuki; Isayama, Akihiko; Hasegawa, Koichi; Suzuki, Sadaaki; Hiranai, Shinichi; Sato, Fumiaki; Wada, Kenji; Yokokura, Kenji; Shimono, Mitsugu; Sawahata, Masayuki; et al.
Fusion Engineering and Design, 86(6-8), p.763 - 767, 2011/10
Times Cited Count：6 Percentile：42.38(Nuclear Science & Technology)Progress of antenna development of the Electron Cyclotron Range of Frequency system for JT-60 SA is presented. Capability of pulse length of 100 s, which requires active cooling for mirrors, and flexibility of beam injection angles in both poloidal and toroidal directions are required for the antenna with high reliability. Mechanical and structural design works of the launcher (antenna and its support with steering structure) based on a linear motion antenna concept are in progress. The key component is a long-stroke bellows which enables to alter poloidal injection angle and a bellows which enables to alter toroidal injection angle. Using a newly fabricated mock-up of the steering structure, it was confirmed that the antenna was mechanically realized for poloidal and toroidal injection angle ranges of -10 to +45 and -15 to +15, respectively. Those angles are consistent with angles required in JT-60SA. The results of thermal and structural analyses are also presented.
Watanabe, Kazuyoshi; Ida, Mizuho; Kondo, Hiroo; Nakamura, Kazuyuki; Wakai, Eiichi
Fusion Engineering and Design, 86(9-11), p.2482 - 2486, 2011/10
Times Cited Count：2 Percentile：17.59(Nuclear Science & Technology)The Engineering Validation and Engineering Design Activities (EVEDA) of the International Fusion Materials Irradiation Facility (IFMIF) are in progress under the Broader Approach (BA) Agreement. As a part of this engineering design, we carried out thermo-structural analysis of the back plate in the IFMIF target. In this analysis, the target assembly of the integrated back plate option was modeled with the nuclear heating to simulate the IFMIF usual operation. The calculation parameters were thermal boundary conditions of a mechanical joint between the target assembly and the beam duct. The calculation results showed the influence of parameters on thermal stress was small. The maximum von Mises stresses occurred at the back plate center and those values, 204 - 218 MPa were lower than half of the yield strength of F82H (455 MPa). The maximum thermal deformations occurred at the same place and those values, about 0.3 mm will be important input parameter for the Li flow stability analysis.
Nakamichi, Masaru; Yonehara, Kazuo; Wakai, Daisuke
Fusion Engineering and Design, 86(9-11), p.2262 - 2264, 2011/10
Times Cited Count：27 Percentile：86.65(Nuclear Science & Technology)Nakamura, Kazuyuki; Furukawa, Tomohiro; Hirakawa, Yasushi; Kanemura, Takuji; Kondo, Hiroo; Ida, Mizuho; Niitsuma, Shigeto; Otaka, Masahiko; Watanabe, Kazuyoshi; Horiike, Hiroshi*; et al.
Fusion Engineering and Design, 86(9-11), p.2491 - 2494, 2011/10
Times Cited Count：10 Percentile：58.64(Nuclear Science & Technology)In IFMIF/EVEDA, tasks for lithium target system are shared to 5 validation tasks (LF1-5) and a design task (LF6). The purpose of LF1 task is to construct and operate the EVEDA lithium test loop, and JAEA has a main responsibility to the performance of the Li test loop. LF2 is a task for the diagnostics of the Li test loop and IFMIF design. Basic research for the diagnostics equipment has been completed, and the construction for the Li test loop will be finished before March in 2011. LF4 is a task for the purification systems with nitrogen and hydrogen. Basic research for the purification equipment has been completed, and the construction of the nitrogen system for the Li test loop will be finished before March in 2011. LF5 is a task for the remote handling system with the target assembly. JAEA has an idea to use the laser beam for cutting and welding of the lip part of the flanges. LF6 is a task for the design of the IFMIF based on the validation experiments of LF1-5.
Shimada, Katsuhiro; Baulaigue, O.*; Cara, P.*; Coletti, A.*; Coletti, R.*; Matsukawa, Makoto; Terakado, Tsunehisa; Yamauchi, Kunihito
Fusion Engineering and Design, 86(6-8), p.1427 - 1431, 2011/10
Times Cited Count：11 Percentile：61.73(Nuclear Science & Technology)Hirose, Takanori; Tanigawa, Hisashi; Yoshikawa, Akira; Seki, Yohji; Tsuru, Daigo; Yokoyama, Kenji; Ezato, Koichiro; Suzuki, Satoshi; Enoeda, Mikio; Akiba, Masato
Fusion Engineering and Design, 86(9-11), p.2265 - 2268, 2011/10
Times Cited Count：5 Percentile：36.88(Nuclear Science & Technology)As one of the most important fabrication technologies of the WCCB TBM, Hot Isostatic Pressing (HIP) joining technology was selected to fabricate the first wall with built-in cooling channel structure made of reduced activation martensitic/ferritic steel, F82H. By using developed HIP technology, a real scale TBM first wall mockup was successfully fabricated. High heat flux test of the fabricated mockup showed the feasibility to with the equivalent conditions of the WCCB TBM operation. The breeder pebble box was successfully fabricated with thin wall cooling pipes and thin plate sleds by Laser welding. With respect to the side walls with built in cooling channels were also fabricated using drilling technology. Assembling of the first wall and side walls is one of the critical fabrication processes of the fabrication of the TBM structure. By using a F82H first wall mockup and side wall mockups, assembling process was demonstrated successfully by Electron Beam welding.
Matsui, Kunihiro; Koizumi, Norikiyo; Hemmi, Tsutomu; Takano, Katsutoshi; Nakajima, Hideo; Osemochi, Koichi*; Savary, F.*
Fusion Engineering and Design, 86(6-8), p.1531 - 1536, 2011/10
Times Cited Count：2 Percentile：17.59(Nuclear Science & Technology)The magnet system for ITER comprises 18 Toroidal Field (TF) Coils using NbSn cable-in-conduit superconductor, which operate at 4.5 K in supercritical helium. Japan Atomic Energy Agency (JAEA) is responsible for the procurement of 9 TF coils as Japanese Domestic Agency (JADA). Before launching the procurement of these coils, reduced and full-scale trials will be performed to determine and optimize the manufacturing process of a TF coil. During the manufacture of the TF coil, heat-treated superconducting cable-in-conduit conductor, whose length may vary during heat treatment, shall be inserted in the grooves of the radial plate (RP), which is part of the mechanical structure supporting the large electromagnetic forces that are of the order of 800 kN/m. The RP also enhance reliability of the electrical insulation that will be tested up to 19 kV DC and 2.5 kV AC for the winding pack to ground. Very accurate tolerances, of the order of 0.01% on the length of the RP grooves and of the wound conductor, are required to enable the insertion of the conductor. Therefore, the development of suitable manufacturing techniques for the RP and for the winding operation is essential to achieve this requirement. JAEA has contracted companies for fabrication trials of a full-scale RP and winding trials of a one-third scale double pancake to verify feasibility of the required tolerances from an industrial view point. Prior to these trials, JAEA developed a preliminary manufacturing plan and then, industry will carry out small-scale trials to demonstrate applicability of the preliminary manufacturing plan before making the reduced and full-scale trials. The small scale trials will include the cover plate welding with the laser welding, the impregnation using the acryl and metal models, and, the mechanical test and the trail bending of the TF conductor. The results of the small-scale trials and progress on the reduced and full-scale trials are presented in this paper.
Takahashi, Koji; Kajiwara, Ken; Okazaki, Yukio*; Oda, Yasuhisa; Sakamoto, Keishi; Omori, Toshimichi*; Henderson, M.*
Fusion Engineering and Design, 86(6-8), p.982 - 986, 2011/10
Times Cited Count：7 Percentile：46.79(Nuclear Science & Technology)In order to optimize the physics performance of ITER, the millimeter (mm) wave design of the equatorial electron cyclotron launcher is modified so that one-third of the total mm-wave injection power can be flipped to drive plasma current in the counter direction. The design change to perform the poloidal beam tilting of 5 at top and bottom beam row is conducted so that more efficient central power deposition is achievable. The opening shape in the blanket shield module (BSM) structure is also optimized to minimize the degradation of the mm-wave transmission efficiency. The degradation is only 0.3%. The modularization design of the steering mirror components and the internal shield, the application of a rail structure to perform the alignment of the steering mirror installation and the space allocation behind the BSM structure are implemented to increase the reliability, the manufacturability and the maintenability of the launcher design.
Hanada, Masaya; Kojima, Atsushi; Tanaka, Yutaka; Inoue, Takashi; Watanabe, Kazuhiro; Taniguchi, Masaki; Kashiwagi, Mieko; Tobari, Hiroyuki; Umeda, Naotaka; Akino, Noboru; et al.
Fusion Engineering and Design, 86(6-8), p.835 - 838, 2011/10
Times Cited Count：17 Percentile：73.93(Nuclear Science & Technology)Neutral beam (NB) injectors for JT-60 Super Advanced (JT-60SA) have been designed and developed. Twelve positive-ion-based and one negative-ion-based NB injectors are allocated to inject 30 MW D
beams in total for 100 s. Each of the positive-ion-based NB injector is designed to inject 1.7 MW for 100s at 85 keV. A part of the power supplies and magnetic shield utilized on JT-60U are upgraded and reused on JT-60SA. To realize the negative-ion-based NB injector for JT-60SA where the injection of 500 keV, 10 MW D beams for 100s is required, R&Ds of the negative ion source have been carried out. High-energy negative ion beams of 490-500 keV have been successfully produced at a beam current of 1-2.8 A through 20% of the total ion extraction area, by improving voltage holding capability of the ion source. This is the first demonstration of a high-current negative ion acceleration of 
1 A to 500 keV. The design of the power supplies and the beamline is also in progress. The procurement of the acceleration power supply starts in 2010.
Hoshino, Tsuyoshi; Terai, Takayuki*
Fusion Engineering and Design, 86(9-11), p.2168 - 2171, 2011/10
Times Cited Count：62 Percentile：96.76(Nuclear Science & Technology)The tritium needed as a fuel for fusion reactors is produced by the neutron capture reaction of lithium-6 (
Li) in tritium breeding materials. However, natural Li contains only about 7.6 at.% Li. In Japan, new lithium isotope separation technique using ionic-liquid impregnated organic membranes have been developed. The improvement in the durability of the ionic-liquid impregnated organic membrane is one of the main issues for stable, long-term operation of electrodialysis cells while maintaining good performance. Therefore, we developed highly-durable ionic-liquid impregnated organic membrane. Both ends of the ionic-liquid impregnated organic membrane were covered by a nafion 324 overcoat to prevent the outflow of the ionic liquid. The transmission of Lithium aqueous solution after 10 hours under the highly-durable ionic-liquid impregnated organic membrane is almost 13%. So this highly-durable ionic-liquid impregnated organic membrane for long operating of electrodialysis cells has been developed through successful prevention of ion liquid dissolution.
Sakasegawa, Hideo; Tanigawa, Hiroyasu; Kano, Sho; Enomoto, Masato*
Fusion Engineering and Design, 86(9-11), p.2541 - 2544, 2011/10
Times Cited Count：16 Percentile：73.93(Nuclear Science & Technology)Reduced Activation Ferritic/Martensitic steels (RAFMs) are leading candidates for the structural material of DEMO blanket module. Through the Broader Approach (BA) activity in Japan, the fabrication techniques for the DEMO blanket module has been studied and developed. In the techniques, the development of joining technique is especially important for fabricating the complicated structure of blanket module. In particular, Hot Isostatic Pressing (HIP) has been applied to joining cooling channels with a rectangular cross section. During and after HIP, the structural material are exposed to various heat treatments such as holding at the HIP temperature, following furnace cooling, 2nd normalizing to refine austenite grains, and 2nd tempering. Microstructural evolutions during these various heat treatments should be focused, because they determine the performance of the blanket module. Especially, fine precipitates such as tantalum and vanadium carbides precipitated at high temperatures greatly affect the creep property, the material toughness, and irradiation resistances of RAF as the structural material. In this work, we have studied the stability of fine precipitates in the F82H-BA07 heat (8Cr-2W-V, Ta) during simulated heat treatments of the blanket fabrication.
