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Miyato, Naoaki; Scott, B. D.*; Yagi, Masatoshi
Proceedings of Plasma Conference 2011 (PLASMA 2011) (CD-ROM), 2 Pages, 2011/11
Seki, Yohji; Hirose, Takanori; Tanigawa, Hisashi; Enoeda, Mikio
Proceedings of Plasma Conference 2011 (PLASMA 2011) (CD-ROM), 2 Pages, 2011/11
Development of test blanket module (TBM) with a water cooled solid breeder is being performed as the primary candidate of ITER-TBM of Japan. Prior to the installation of each TBM, it is necessary to develop the capability of the prediction analyses of all essential functions of the blanket to validate the analyses tools by the TBM. Especially the prediction tool of tritium concentration in the blanket system is one of the most important issues to control tritium recovery. From this view point, this paper discusses the flow phenomena and the tritium transport of the helium purge gas in the pebble bed. By prediction of purge gas flow using a numerical simulation, the result indicates tritium concentration depended on the position of the breeder layer. Namely, the large concentration still remains near the wall with approaching to an outlet.
Kondo, Hiroo; Furukawa, Tomohiro; Hirakawa, Yasushi; Iuchi, Hiroshi; Kanemura, Takuji; Ida, Mizuho; Watanabe, Kazuyoshi; Horiike, Hiroshi*; Yamaoka, Nobuo*; Matsushita, Izuru*; et al.
Proceedings of Plasma Conference 2011 (PLASMA 2011) (CD-ROM), 2 Pages, 2011/11
The EVEDA Li test loop (ELTL) successfully completed its construction and commissioning in the frame work of the IFMIF/EVEDA as one of the ITER-BA. The construction was started on Nov. 2009 in the O-arai site of the Japan Atomic Energy Agency and completed on the middle of Nov. 2010. In the commissioning conducted subsequently, the following tests were performed: (1) Li ingots installation into the ELTL, (2) Li charging and draining operation, (3) Li circulation tests. In a final phase of the circulation test, stable liquid Li flow at a velocity of 5 m/s was successfully achieved.
Tsujimoto, Kazufumi
Proceedings of Plasma Conference 2011 (PLASMA 2011) (CD-ROM), 2 Pages, 2011/11
Neutron beam is used for a wide variety of scientific and engineering research, such as materials and life science, and industrial applications. There are three kinds of neutron sources: (1) isotopic neutron source, (2) reactor sources, and (3) accelerator-based neutron sources. Recently, high intensity spallation neutron sources with high energy proton accelerator became to offer similar capabilities to research reactors, as well as a few extra features. In Japan, the JSNS (Japan Spallation Neutron Source) was constructed and operated at J-PARC (Japan Proton Accelerator Research Complex). Moreover, as future utilization of spallation neutron, research and development for accelerator-driven subcritical system have been performed.
Shibama, Yusuke; Masaki, Kei; Nakamura, Shigetoshi; Kaminaga, Atsushi; Miyo, Yasuhiko; Sakurai, Shinji; Shibanuma, Kiyoshi; Sakasai, Akira
no journal, ,
JT-60SA is a fully superconducting coil tokamak upgraded from the JT-60U. This paper focuses on the vacuum vessel (VV, 150 tons) and cryostat (610 tons), whose structural concepts are developed from the ASME BPVC Section VIII Division 2. The VV is a stainless steel torus double-walled, which achieves high electrical resistivity in the toroidal and high stiffness in the light structure. The cryostat is large size vacuum thermal insulation vessel. The present status of both vessels is reported.
Nishitani, Takeo; Tobita, Kenji; Ishikawa, Masao; Shinohara, Koji
no journal, ,
no abstracts in English
Yamaguchi, Toshikazu*; Takeichi, Tensei*; Komatsu, Reiji*; Fukunari, Masafumi*; Komurasaki, Kimiya*; Oda, Yasuhisa; Kajiwara, Ken; Takahashi, Koji; Sakamoto, Keishi
no journal, ,
no abstracts in English
Ejiri, Mitsuru*; Kitamura, Kazunori*; Araki, Takao*; Omori, Junji*; Asano, Shiro*; Hayakawa, Atsuro*; Shibama, Yusuke; Masaki, Kei; Sakasai, Akira
no journal, ,
In the operation of tokamak, such loads as electromagnetic and seismic are assumed to be imposed on the vacuum vessel (VV), and not a little thermal expansion takes place when VV is baked. The gravity support leg (GS) has to support the loads described above in addition to the dead weight of VV including in-vessel components and compensate deformation. The GS is equipped with plate spring (PS) to have both stiffness and flexibility. In this study, the buckling strength of the PSs was evaluated. The effect of the initial imperfection of the PSs which is assumed to result from machining or welding process on the buckling strength was also studied. It is concluded that GS has sufficient buckling strength against assumed initial imperfections.
Tanimoto, Tsuyoshi; Nishiuchi, Mamiko; Mishima, Yosuke*; Kikuyama, Kenshiro*; Morioka, Tomoya*; Morita, Kiyoshi*; Kanasaki, Masato; Pirozhkov, A. S.; Yogo, Akifumi; Ogura, Koichi; et al.
no journal, ,
Yanagi, Yutaka*; Shibui, Masanao*; Kanahara, Toshio*; Mochida, Tsutomu*; Ejiri, Mitsuru*; Asano, Shiro*; Shibama, Yusuke; Masaki, Kei; Sakasai, Akira
no journal, ,
JT-60SA Vacuum Vessel (VV) has D-shaped cross section and double-walled structure. It consists of the inner and outer wall reinforced by poloidal ribs and is made of SUS316L (Co
0.05wt%). The welding outer wall on rib (so called continuous plug) is performed from the outside of double-wall. Since it is difficult to confirm the penetration bead from the inside of double-wall, an incomplete penetration is assumed to be included in this welded joint. In this study, the fatigue test of continuous plug welded joint with an artificial incomplete penetration was performed to investigate the effect of the incomplete penetration on fatigue behavior and fatigue strength.
Kawashima, Hisato; Shimizu, Katsuhiro; Hoshino, Kazuo; Takizuka, Tomonori*; Sakurai, Shinji
no journal, ,
For SONIC simulation on JT-60SA divertor, the heat flux limiter is introduced in the ion parallel heat transport besides electron one. Changing the limit factor from 
= 0.5 to 10, density decrement and temperature increment in the edge-plasma are remarkable at = 0.5 in comparison with a case without limiter. Sensitivity on the radial particle or thermal diffusivity is surveyed with range of D = 0.1
1 m
/s and 
= 0.12 m/s. Divertor heat flux increases from 7.5 to 10.5 MW/m with decrease of D. This sensitivity is stronger than that for .
Kubo, Hirotaka; Arai, Takashi; Hasegawa, Koichi; Hoshi, Ryo*; Kawashima, Hisato; Maesaki, Yoshitaka; Masaki, Kei; Sawai, Hiroaki; Shibanuma, Kiyoshi; Tabe, Masato; et al.
no journal, ,
The JT-60SA tokamak, which is a large superconducting tokamak, needs to be assembled consistently with high precision; assembly of the JT-60SA tokamak has been studied. The absolute coordinate system for the assembly is defined on the basis of the coordinate system of the JT-60 torus hall. The origin ((x, y, z) = (0, 0, 0)) of the absolute coordinate system is defined to be the center of the VV in the plasma operation. A consistent global scenario of the assembly is studied. Assembly procedures and tools for major components such as the TFCs are studies.
Shinto, Katsuhiro; Wada, Motoi*; Nishida, Tomoaki*; Kisaki, Masashi*; Tsumori, Katsuyoshi*; Nishiura, Masaki*; Kaneko, Osamu*; Sasao, Mamiko*
no journal, ,
We have proposed a negative ion beam probe system as a new scheme to diagnose beam profiles of high power positive ion beams. We show the present status of the proof-of-principle experiment for the negative ion beam probe system performed at NIFS NBI test stand. A negative hydrogen ion source which produces a rectangular shape beam was installed at the diagnostic chamber in the NBI test stand and the total current of H
beam extracted from the ion source was measured. We obtained the total H beam current of 10 
A with the beam energy of 3 kV.
Kojima, Atsushi; Hanada, Masaya; JT-60NBI Group
no journal, ,
30-34 MW neutral deuterium beams are injected to JT-60SA plasmas by using neutral beam injectors with 24 positive ion sources for 12 units and 2 negative ion sources for 1 unit. As for the positive NBI, 2MW, 30s injections has already achieved with temperature increase of cooling water saturated. A beam duct for Re-ionization loss is required to be cooled additionally. The existing power supplies are applicable by enhancing the heat tolerance. Long pulse injections with higher stray magnetic field than JT-60U could be carried out by masking partial apertures whose beamlets missed the beam damp. As for the negative NBI, productions of 500keV, 3A, 0.8s and 350keV, 3MW, 30s beams has been achieved so far. Recently the database for vacuum insulation has been obtained to achieve stable acceleration of 500keV beams. Long pulse production of the negative ions are planned by constructing the new test stand of the negative ion source with temperature-controlled plasma grid.
Atsumi, Kohei*; Sugawara, Shuhei*; Yamaguchi, Tomoki*; Saigusa, Mikio*; Oda, Yasuhisa; Takahashi, Koji; Kajiwara, Ken; Sakamoto, Keishi
no journal, ,
no abstracts in English
Nakamura, Tatsufumi; Esirkepov, T. Z.; Koga, J. K.; Pirozhkov, A. S.; Bulanov, S. V.; Kando, Masaki
no journal, ,
The concept of flying mirror is proposed to increase the laser irradiance, and generating the tunable compact X-ray source. The amplification factor is expressed by using Lorentz factor corresponding to the phase velocity of plasma wave 
, as 
. Although the phase velocity of plasma wave is approximated as the laser group velocity in the one-dimensional model, it becomes lower at near the wave-breaking. In this study, we elucidate the plasma phase velocity including multi-dimensional effect and its nonlinear evolution towards wave-breaking by using two-dimensional PIC simulations. Its dependence on laser intensity, spot size, pulse duration, and plasma density is explored.
Honda, Mitsuru; Kikuchi, Mitsuru; Azumi, Masafumi*
no journal, ,
Fujita, Takaaki; JT-60SA Team
no journal, ,
Kamiya, Kensaku; Honda, Mitsuru; Urano, Hajime; Yoshida, Maiko; Sakamoto, Yoshiteru; Matsunaga, Go; Oyama, Naoyuki; Koide, Yoshihiko; Kamada, Yutaka
no journal, ,
Depending on the direction of the external tangential momentum input, substantial changes in not only toroidal but also poloidal flows for the carbon impurity ions are observed at around the Er-well region. The shear in the edge Er becomes wider in the co-NBI case, while the edge Er-well becomes deeper in the counter-NBI case.
Koizumi, Norikiyo; Matsui, Kunihiro; Hemmi, Tsutomu; Chida, Yutaka; Iguchi, Masahide
no journal, ,
no abstracts in English