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Abe, Kanako*; Nakajima, Hideo; Hamada, Kazuya; Okuno, Kiyoshi; Kakui, Hideo*; Yamaoka, Hiroto*; Maruyama, Naoyuki*
IEEE Transactions on Applied Superconductivity, 16(2), p.807 - 810, 2006/06
Times Cited Count：12 Percentile：53.00(Engineering, Electrical & Electronic)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.
Takahashi, Yoshikazu; Yoshida, Kiyoshi; Mitchell, N.*; Bessette, D.*; Nunoya, Yoshihiko; Matsui, Kunihiro; Koizumi, Norikiyo; Isono, Takaaki; Okuno, Kiyoshi
IEEE Transactions on Applied Superconductivity, 14(2), p.1410 - 1413, 2004/06
Times Cited Count：10 Percentile：47.71(Engineering, Electrical & Electronic)Cable-in-conduit conductors that consist of about 1,000 Nb
Sn strands with an outer diameter of about 0.8mm, have been designed for the TF and CS coils of the ITER. The rated current of these coils is 40 -68kA. Two joint types (Butt and Lap) were developed during the CS Model Coil project. The performance of these joints was evaluated during the operating tests and the satisfied results were obtained. The joints of the TF coils are located outside of the winding in a region where the magnetic field is about 2.1T, a very low value as compared to the maximum field of 11.8T at the winding. The CS joints are located at the coil outer diameter and embedded within the winding pack due to the lack of the space. The maximum fields at the CS joint and winding are 3.5 and 13T, respectively. For the TF coils and the CS, the joints are cooled in series with the conductor at the outlet. The maximum temperature increase due to the joule heating in the joints is set at 0.15K to limit the heat load on the refrigerator. It is shown that both joint types are applicable to the ITER coils.
Takeda, Nobukazu; Nakahira, Masataka; Tada, Eisuke; Fujita, Satoshi*; Fujita, Takafumi*
Nihon Jishin Kogakkai Rombunshu (Internet), 4(3), p.298 - 304, 2004/04
ITER is a Tokamak-type international fusion experimental device composed of superconducting magnets, a vacuum vessel, and so on. These are operated at a quie wide temperature ranging from 4K to 200 degree C. For this, multiple plates have been chosen as the machine support so as to peovide flexibility in the radial direction while keeping high rigidity vertically. This results in a low natural frequency of around 4Hz in the horizontal direction. Since those structures are designed in accordance with the IAEA seismic acceleration of 0.2g as a reference, a seismic isolation is required if earthquake-proof larger than 0.2g is necessary. Considering these conditions, analytical and experimental studies have been conducted to characterize the ITER dynamic response in Japan. This paper outlines the latest status on seismic design for ITER in Japan and evaluation on tokamak dynamic response and verification tests using scaled tokamak model.
Al cable-in-conduit conductorKoizumi, Norikiyo; Nunoya, Yoshihiko; Matsui, Kunihiro; Nakajima, Hideo; Ando, Toshinari*; Okuno, Kiyoshi
Superconductor Science and Technology, 16(9), p.1092 - 1096, 2003/09
Times Cited Count：9 Percentile：45.21(Physics, Applied)A 13T-46kA NbAl insert (ALI) has been developed in the ITER-EDA to demonstrate the applicability of react-and-wind technique to TF coil fabrication. Since it is estimated that a conductor is subjected to 0.4% bending strain after heat treatment when the react-and-wind method is applied, 0.4% bending strain was artificially applied to the ALI conductor. Thus, the conductor is subjected to the thermal and bending strains. The strains due to thermal stress and conductor bending are estimated from the critical current test results of the ALI to be 0.4% and 0%, respectively. The thermal strain showed good agreement with the prediction but the axial strain was not applied to the strand by the 0.4% bending. In addition, the evaluated strain of the NbAl conductor is compared with those of NbSn conductors. There was an unexpected strain in the NbSn conductors but the one was not observed in the NbAl conductor. One of the explanations is higher rigidity of the NbAl strand. This shows that an NbAl conductor is suitable to the application to large magnets.
Nunoya, Yoshihiko; Sugimoto, Makoto; Isono, Takaaki; Hamada, Kazuya; Matsui, Kunihiro; Okuno, Kiyoshi; CS Model Coil Test Group
Teion Kogaku, 37(10), p.523 - 530, 2002/10
Vurrent sharing temperature (Tcs) measurement of ITER toroidal field insert was performed. The coil is Nb
Sn superconducting coil and was installed inside of the ITER CS model coil as a backup field coil. Relation between the voltage of individual strand composing TF insert conductor and the measured voltage using the taps on the jacket is investigated and the evaluation method for Tcs measurement was established. The obtained results shows that there was discrepancy between the expected value from the strand data and the measured value which is lower by about 1.2K. Some discrepancy was already observed just after cool down of the insert before energizing.
Hamada, Kazuya; Kawano, Katsumi; Matsui, Kunihiro; Kato, Takashi; Sugimoto, Makoto; Hara, Eiji*; Okuno, Kiyoshi; Egorov, S. A.*; Rodin, I.*; Sytnikov, V. E.*; et al.
Teion Kogaku, 37(10), p.531 - 538, 2002/10
In the Engineering Design Activities of the International Thermonuclear Experimental Reactor (ITER), Toroidal Field (TF) Insert have been developed and tested successfully. In the experiment, pressure drop performance of TF insert was investigated. There were two purposes for the investigation. One is to verify the pressure drop prediction using correlations proposed by various researchers. Second is to observe a behavior of pressure drop under the electromagnetic force. The pressure drops of TF insert decreased by around 12% during current-carrying operation of 46kA at 13T. After several current-carrying operation, the friction factor of TF insert has finally reached a value which is around 12% lower than that of virgin state and was not recovered even if there were zero current. It is considered that a deformation of cable cross section inside the conductor jacket appears due to electromagnetic force and a new flow path in the jacket is generated.
Al multifilamentary strand fabricated by a jelly-roll methodTakahashi, Yoshikazu; Koizumi, Norikiyo; Nunoya, Yoshihiko; Takaya, Yoshiyuki*; Tsuji, Hiroshi
IEEE Transactions on Applied Superconductivity, 12(2), p.1799 - 1803, 2002/06
Times Cited Count：5 Percentile：34.72(Engineering, Electrical & Electronic)JAERI has been developing jelly-roll processed multifilamentary NbAl/Cu strands for the Toroidal Field (TF) coils of fusion tokamak machines since 1986, in cooperation with industries. One ton of mass-produced strands were successfully manufactured for the 13T-46kA NbAl insert which will be tested using the ITER Central Solenoid model coil. The critical current of the Nb3Al strand developed for the ITER project was measured in temperatures from 4.2 K to 15 K and in applied magnetic fields up to 16 T. An empirical equation for the critical current density was devised using these data and the pinning force scaling method. Good agreement between this equation and the measured data is obtained in the operating condition of the ITER machine. The equation is useful in evaluating the performance of the full-size conductor that consists of 1,152 strands and in establishing the optimum design criteria for the conductor in fusion machines.
Sugimoto, Makoto; Isono, Takaaki; Matsui, Kunihiro; Nunoya, Yoshihiko; Tsutsumi, Fumiaki*; Tamiya, Tadatoshi*; Oshikiri, Masayuki*; Wakabayashi, Hiroshi*; Okuno, Kiyoshi; Tsuji, Hiroshi
JAERI-Tech 2001-085, 104 Pages, 2001/12
JAERI-Tech-2001-085.pdf:4.64MB
no abstracts in English
; Nakajima, Hideo; Nunoya, Yoshihiko; Miura, Yushi; Kawasaki, T.*; Tsuji, Hiroshi
Advances in Cryogenic Engineering Materials, 44, p.73 - 80, 1998/00
no abstracts in English
Koizumi, Koichi; Hasegawa, Mitsuru*; Yoshida, Kiyoshi
JAERI-M 91-121, 200 Pages, 1991/08
no abstracts in English
Sakurai, Takeru; Iguchi, Masahide; Saito, Toru; Nakahira, Masataka
no journal, ,
no abstracts in English
Hemmi, Tsutomu; Kajitani, Hideki; Matsui, Kunihiro; Mizutani, Takumi; Yamane, Minoru; Sakaguchi, Kaori; Ando, Shinji; Takano, Katsutoshi; Koizumi, Norikiyo
no journal, ,
JAEA has responsibility of procurement of 9 ITER Toroidal Field (TF) coils in ITER. Prior to TF coil fabrication, JAEA started to fabricate three dummy double pancakes (DPs) in order to confirm the commissioning of the facilities for DP fabrication and establish the manufacturing process of the DP. Fabrication of the dummy DP as full-scale trials has been started from October, 2013. In this full-scale trial, the control of conductor length with 
0.01%, flatness of radial plate (RP) with 2 mm and flatness of DP after CP welding with 2 mm were achieved and conductor elongation due to heat treatment was evaluated. Based on these results, TF coil winding has been started. The conductor winding has been already completed for 11 DPs of the TF coil and 10 DPs were heat treated. The conductor elongation is within expected value of 0.02%.
