Iwamoto, Osamu; Iwamoto, Nobuyuki; Kunieda, Satoshi; Minato, Futoshi; Nakayama, Shinsuke; Abe, Yutaka*; Tsubakihara, Kosuke*; Okumura, Shin*; Ishizuka, Chikako*; Yoshida, Tadashi*; et al.
Journal of Nuclear Science and Technology, 60(1), p.1 - 60, 2023/01
Aoki, Takeshi; Isaka, Kazuyoshi; Sato, Hiroyuki; Ohashi, Hirofumi
Proceedings of 2020 International Conference on Nuclear Engineering (ICONE 2020) (Internet), 7 Pages, 2020/08
The flow distribution analysis performed in the HTGR design has to take into account the interaction thermal and radiation deformations of the graphite structure, and the gaps between the graphite structures forming unintended flow. In the present study, a user-friendly flow network calculation code (FNCC) has been developed on the basis of experiences of High Temperature engineering Test Reactor (HTTR) design for HTGR design with enhanced compatibility with other HTGR design codes and with considering graphite block deformation in iteration process without manual control. The validation of FNCC was performed for the one-column flow distribution test. The analytical results using FNCC showed good agreement with the experimental results. It is concluded that FNCC was validate for the analysis of distributions of flowrate and pressure for the flow network model including the unintended flow paths in prismatic-type HTGRs.
Samarakoon, A. M.*; Takahashi, Mitsuru*; Zhang, D.*; Yang, J.*; Katayama, Naoyuki*; Sinclair, R.*; Zhou, H. D.*; Diallo, S. O.*; Ehlers, G.*; Tennant, D. A.*; et al.
Scientific Reports (Internet), 7(1), p.12053_1 - 12053_8, 2017/09
Kondo, Yasuhiro; Asano, Hiroyuki*; Chishiro, Etsuji; Hirano, Koichiro; Ishiyama, Tatsuya; Ito, Takashi; Kawane, Yusuke; Kikuzawa, Nobuhiro; Meigo, Shinichiro; Miura, Akihiko; et al.
Proceedings of 28th International Linear Accelerator Conference (LINAC 2016) (Internet), p.298 - 300, 2017/05
We have constructed a linac for development of various accelerator components at J-PARC. The ion source is same as the J-PARC linac's, and the RFQ is a used one in the J-PARC linac. The beam energy is 3 MeV and nominal beam current is 30 mA. The accelerator has been already commissioned, and the first development program, laser-charge-exchange experiment for the transmutation experimental facility, has been started. In this paper, present status of this 3-MeV linac is presented.
Saito, Hiroshi; Sato, Yasushi*; Sakamoto, Atsushi*; Torikai, Kazuyoshi; Fukushima, Shigeru; Sakao, Ryota; Taki, Tomihiro
JAEA-Technology 2015-063, 119 Pages, 2016/03
Ningyo-toge Environmental Engineering Center has been conducting environmental remediation of the Ningyo-toge Uranium Mine, after decades of mine-related activities were terminated. Its purposes are to take measures to ensure safety and radiation protection from the exposure pathways to humans in future, and to prevent the occurrence of mining pollution. As part of the remediation, upstream part of the Yotsugi Mill Tailings Pond, the highest prioritized facility, has been remediated to fiscal year 2012. Multi-layered capping has been constructed using natural material, after specifications and whole procedure being examined in terms of long-term stability, radiation protection, economics, etc. Monitoring has been carried out to confirm the effectiveness of the capping, in terms of settlement, dose and radon exhalation rates, etc. Monitoring of drainage volume of penetrated rainwater is planned. Accumulated data will be examined and used for remediation of downstream part of the Pond.
Sato, Kentaro*; Matsuura, Masato*; Fujita, Masaki*; Kajimoto, Ryoichi; Ji, S.*; Ikeuchi, Kazuhiko*; Nakamura, Mitsutaka; Inamura, Yasuhiro; Arai, Masatoshi; Enoki, Masanori*; et al.
JPS Conference Proceedings (Internet), 3, p.017010_1 - 017010_6, 2014/06
Yamamoto, Tsuyoshi; Hashimoto, Yasunori*; Serizawa, Yasunori*; Inamoto, Shuji*; Sato, Kazuyoshi; Sugie, Tatsuo; Takeuchi, Masaki; Kawano, Yasunori
Fusion Engineering and Design, 89(5), p.532 - 535, 2014/05
The diagnostic systems are essential for the plasma control and physics understandings. JAEA has proposed the new concept of supervisory system which manages operation sequences, current state and configuration parameters for the measurement based on our experiences in operating plasma diagnostic systems. We designed the supervisory system satisfying the requirements from both CODAC system and diagnostic systems. In our design, the tool which converts operational steps described as flowcharts into EPICS Records templates is introduced. This tool will ensure reduction of the system designers' efforts. We also designed the sequencing simulator that can submit transition commands internally instead of CODAC system for the calibration and commissioning. The mechanism which changes the limit values and consistency check algorithms in accordance with the conditions of the diagnostics system is also proposed.
Ishii, Kenji; Fujita, Masaki*; Sasaki, Takanori*; Minola, M.*; Dellea, G.*; Mazzoli, C.*; Kummer, K.*; Ghiringhelli, G.*; Braicovich, L.*; Toyama, Takami*; et al.
Nature Communications (Internet), 5, p.3714_1 - 3714_8, 2014/04
Ohashi, Hirofumi; Sato, Hiroyuki; Tazawa, Yujiro; Aihara, Jun; Nomoto, Yasunobu; Imai, Yoshiyuki; Goto, Minoru; Isaka, Kazuyoshi; Tachibana, Yukio; Kunitomi, Kazuhiko
JAEA-Technology 2013-017, 71 Pages, 2014/02
Japan Atomic Energy Agency (JAEA) has started a conceptual design of a 50 MWt small-sized high temperature gas cooled reactor (HTGR) for steam supply and electricity generation (HTR50S). Though the safety design of HTR50S was determined based on that of the High Temperature Engineering Test Reactor (HTTR) for the early deployment of HTR50S, the shutdown cooling system, which is the forced cooling heat removal system, was categorized as non-safety class to optimize the protection to provide the highest level of safety that can reasonably be achieved, and the vessel cooling system, which is categorized as the safety class system, was designed as a passive safety features. The preliminary safety analysis of HTR50S for the rupture of co-axial hot gas duct in primary cooling system and the tube rupture of steam generator was conducted to confirm the adequacy of the safety design. It was confirmed that the analysis results satisfied the acceptance criteria.
Fukushima, Shigeru; Taki, Tomihiro; Saito, Hiroshi; Torikai, Kazuyoshi; Sato, Yasushi*
Nihon Chikasui Gakkai 2013-Nen Shuki Koenkai Koen Yoshi, p.258 - 263, 2013/10
no abstracts in English
Pitcher, C. S.*; Barnsley, R.*; Bertalot, L.*; Encheva, A.*; Feder, R.*; Friconneau, J. P.*; Hu, Q.*; Levesy, B.*; Loesser, G. D.*; Lyublin, B.*; et al.
Fusion Science and Technology, 64(2), p.118 - 125, 2013/08
The port-based plasma diagnostic infrastructure on ITER is described, including the port plugs, the interspace support structure and port cell structure. These systems are modular in nature with standardized dimensions. The design of the equatorial and upper port plugs and their modules is discussed, as well as the dominant loading mechanisms. The port infrastructure design has now matured to the point that port plugs are now being populated with multiple diagnostics supplied by a number of ITER partners - two port plug examples are given.
Pitcher, C. S.*; Barnsley, R.*; Feder, R.*; Hu, Q.*; Loesser, G. D.*; Lyublin, B.*; Padasalagi, S.*; Pak, S.*; Reichle, R.*; Sato, Kazuyoshi; et al.
Fusion Engineering and Design, 87(5-6), p.667 - 674, 2012/08
Nishimura, Masahiro; Sato, Hiroyuki; Kamide, Hideki; Ohshima, Hiroyuki; Nagasawa, Kazuyoshi*; Imai, Yasutomo*
Proceedings of 20th International Conference on Nuclear Engineering and the ASME 2012 Power Conference (ICONE-20 & POWER 2012) (DVD-ROM), 10 Pages, 2012/07
Feature of stream regime in the subchannel existing wrapping wire was visualized in vertical and horizontal plane by the PIV method. And the time averaged velocity field in the horizontal plane was reconstructed from the two vertical plane data in different directions. A detailed simulation code based on FEM was applied to the experimental analysis. The calculated velocity distributions were consistent with the experimental data.
Sato, Kazuyoshi; Yaguchi, Eiji; Pitcher, C. S.*; Walker, C.*; Encheva, A.*; Kawano, Yasunori; Kusama, Yoshinori
Fusion Engineering and Design, 86(6-8), p.1264 - 1267, 2011/10
no abstracts in English
Adare, A.*; Afanasiev, S.*; Aidala, C.*; Ajitanand, N. N.*; Akiba, Yasuyuki*; Al-Bataineh, H.*; Alexander, J.*; Aoki, Kazuya*; Aphecetche, L.*; Armendariz, R.*; et al.
Physical Review C, 83(6), p.064903_1 - 064903_29, 2011/06
Transverse momentum distributions and yields for , and in collisions at = 200 and 62.4 GeV at midrapidity are measured by the PHENIX experiment at the RHIC. We present the inverse slope parameter, mean transverse momentum, and yield per unit rapidity at each energy, and compare them to other measurements at different collisions. We also present the scaling properties such as and scaling and discuss the mechanism of the particle production in collisions. The measured spectra are compared to next-to-leading order perturbative QCD calculations.
Adare, A.*; Afanasiev, S.*; Aidala, C.*; Ajitanand, N. N.*; Akiba, Yasuyuki*; Al-Bataineh, H.*; Alexander, J.*; Aoki, Kazuya*; Aphecetche, L.*; Aramaki, Y.*; et al.
Physical Review C, 83(4), p.044912_1 - 044912_16, 2011/04
Measurements of electrons from the decay of open-heavy-flavor mesons have shown that the yields are suppressed in Au+Au collisions compared to expectations from binary-scaled collisions. Here we extend these studies to two particle correlations where one particle is an electron from the decay of a heavy flavor meson and the other is a charged hadron from either the decay of the heavy meson or from jet fragmentation. These measurements provide more detailed information about the interaction between heavy quarks and the quark-gluon matter. We find the away-side-jet shape and yield to be modified in Au+Au collisions compared to collisions.
Kajimoto, Ryoichi; Nakamura, Mitsutaka; Inamura, Yasuhiro; Mizuno, Fumio; Nakajima, Kenji; Kawamura, Seiko; Yokoo, Tetsuya*; Nakatani, Takeshi; Maruyama, Ryuji; Soyama, Kazuhiko; et al.
Journal of the Physical Society of Japan, 80(Suppl.B), p.SB025_1 - SB025_6, 2011/01
Nakasone, Yuji*; Sato, Kazuyoshi; Takahashi, Yukio*
Proceedings of 2010 ASME Pressure Vessels and Piping Conference (PVP 2010) (CD-ROM), 5 Pages, 2010/07
no abstracts in English
Sato, Kazuyoshi; Omori, Junji; Kondoh, Takashi; Hatae, Takaki; Kajita, Shin*; Ishikawa, Masao; Neyatani, Yuzuru; Ebisawa, Katsuyuki*; Kusama, Yoshinori
Fusion Engineering and Design, 84(7-11), p.1713 - 1715, 2009/06
Engineering analyses have been performed for the representative diagnostic upper port plug of ITER. Maintenance and integration design have been also carried out for the diagnostic components to be installed in the upper port plug. From the electromagnetic and structural analyses, it has come up an important problem to suppress the displacement of the upper port plug rather than to reduce the produced stress. Reducing the EM force will help to decrease the severity of potential displacement. Maximum displacement of the port plug decreases with increasing in the number of slits in a manner that the displacement would seem to be less than the design tolerance. A proposed low body roller and inner frame may enhance maintenance and integration. These studies and designs have established the design basis for the diagnostic upper port plug.
Tanabe, Tetsuo*; Sugiyama, Kazuyoshi*; Shibahara, Takahiro*; Hirohata, Yuko*; Yoshida, Masafumi; Masaki, Kei; Sato, Masayasu
Journal of Nuclear Materials, 390-391, p.705 - 708, 2009/06
no abstracts in English