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Kunieda, Satoshi; Iwamoto, Osamu; Iwamoto, Nobuyuki; Minato, Futoshi; Okamoto, Tsutomu; Sato, Tatsuhiko; Nakashima, Hiroshi; Iwamoto, Yosuke; Iwamoto, Hiroki; Kitatani, Fumito; et al.
JAEA-Conf 2016-004, p.41 - 46, 2016/09
Neutron- and proton-induced cross-section data are required in a wide energy range beyond 20 MeV, for the design of accelerator applications. New evaluations are performed with recent knowledge in the optical and pre-equilibrium model calculations. We also evaluated cross-sections for p+
Li and p+
Be which have been highly requested from a medical field. The present high-energy nuclear data library, JENDL-4.0/HE, includes evaluated cross-sections for incident neutrons and protons up to 200 MeV (for about 130 nuclei). We overview substantial features of the library, i.e., (1) systematic evaluation with CCONE code, (2) challenges for evaluations of light nuclei and (3) inheritance of JENDL-4.0 and JENDL/HE-2007. In this talk, we also focus on the results of benchmark calculation for neutronics to show performance of the present library.
Okamoto, Tsutomu; Minato, Futoshi; Koura, Hiroyuki; Iwamoto, Osamu
JAEA-Data/Code 2015-029, 30 Pages, 2016/03
JAEA-Data-Code-2015-029.pdf:1.81MB
The booklet "chart of the nuclides" is issued every 4 years since 1976 from Nuclear Data Center, JAEA. The chart of the nuclides for WWW (World Wide Web) was developed in 1999 in order to be available from internet browser. Internet connection speeds, browser functions and JavaScript libraries has, however, progressed at present compared with the internet technology in those days. In connection with the release of the 2014 edition of the chart of the nuclides, the interface of the WWW chart of the nuclides has been improved by introducing new internet technologies aiming at enhancing convenience on accessibilities via browsers. We introduced a scrolling screen that would make capabilities of easy screen movement on a map with the addition of the drag scrolling function. Considering smart phone access, the light-weight edition which introduced automatic switch was prepared. The new system results in reduction in access time and usefulness in mobile environment. The method of making figures of the chart was reconsidered due to addition of new decay schemes to the 2014 edition. SVG (Scalable Vector Graphics) was adopted so as to make figures easily. It is concluded that the accessibilities of WWW chart of the nuclides are substantially improved from the previous version by introducing the new technologies.
Tsuji, Nobumasa*; Nakano, Masaaki*; Takada, Eiji*; Tokuhara, Kazumi*; Ohashi, Kazutaka*; Okamoto, Futoshi*; Tazawa, Yujiro; Inaba, Yoshitomo; Tachibana, Yukio
Proceedings of 6th International Topical Meeting on High Temperature Reactor Technology (HTR 2012) (USB Flash Drive), 9 Pages, 2012/10
Passive heat removal performance of the reactor vessel cavity cooling system (RCCS) is of primary concern for enhanced inherent safety of HTGR. In a loss of forced cooling accident, decay heat must be removed by radiation and natural convection of RCCS. Thus thermal hydraulic analysis of reactor internals and RCCS is powerful means for evaluation of the heat removal performance of RCCS. The thermal hydraulic analyses using CFD computation tools are conducted for normal operation of the High Temperature Engineering Test Reactor (HTTR) and are compared to the temperature distribution of measured data. The calculated temperatures on outer faces of the permanent side reflector (PSR) blocks are in fair agreement with measured data. The transient analysis for decay heat removal mode in HTTR is also conducted.
C high temperature gas-cooled reactorNakano, Masaaki*; Takada, Eiji*; Tsuji, Nobumasa*; Tokuhara, Kazumi*; Ohashi, Kazutaka*; Okamoto, Futoshi*; Tazawa, Yujiro; Tachibana, Yukio
Proceedings of 6th International Topical Meeting on High Temperature Reactor Technology (HTR 2012) (USB Flash Drive), 6 Pages, 2012/10
The conceptual core design study of High Temperature Gas-cooled Reactor (HTGR) is performed. The major specifications are 600 MW thermal output, 950C outlet coolant temperature, prismatic core type, enriched uranium fuel. The decay heat in the core can be removed with only passive measures, for example, natural convection reactor cavity cooling system (RCCS), even if any electricity is not supplied (station blackout). The transient thermal analysis of the depressurization accident in the case the primary coolant decreases to the atmosphere pressure shows that the fuels and the reactor pressure vessel temperatures are kept under their safety limit criteria. The fission product release, 
Ag and 
Cs from the fuels under the normal operation is small as to make maintenance of devices in the primary cooling system, such as a gas turbine, without remote maintenance. The HTGRs can achieve the advanced safety features based on their inherent passive safety characteristics.
Ohashi, Kazutaka; Nishihara, Tetsuo; Kunitomi, Kazuhiko; Nakano, Masaaki*; Tazawa, Yujiro*; Okamoto, Futoshi*
Nihon Genshiryoku Gakkai Wabun Rombunshi, 7(1), p.32 - 43, 2008/03
Interests on the development of the Very High-Temperature Gas-Cooled Reactor (VHTR), of which the reactor outlet temperature is 950C or much higher, are recently increasing world-widely and it was selected as one of the candidate reactor types of the GIF. Japan Atomic Energy Agency has already initiated R&D efforts on the electricity and hydrogen co-generation plant with VHTR system, GTHTR300C. Although technical feasibility of its VHTR reactor using Pin-in-block fuel, which has experience to be already used in the HTTR, has been shown fundamentally, more improvements of the core performances, such as decrease of the occupational exposure doses during the plant maintenance, are desired. This report presents the results of the conceptual core design study using Multi-hole type fuel and the study on the occupational exposure doses. The latter results shows much better plant maintainability compared to the previous results of the GTHTR-300.
Okamoto, Futoshi*; Tozawa, Katsuhiro*; Nishihara, Tetsuo; Kunitomi, Kazuhiko
no journal, ,
no abstracts in English
Tazawa, Yujiro*; Okamoto, Futoshi*; Ohashi, Kazutaka; Kunitomi, Kazuhiko
no journal, ,
no abstracts in English
Tsuji, Nobumasa*; Okamoto, Futoshi*; Murakami, Tomoyuki; Kunitomi, Kazuhiko
no journal, ,
no abstracts in English
Yan, X.; Kunitomi, Kazuhiko; Tsuji, Nobumasa*; Okamoto, Futoshi*
no journal, ,
Safety goal for VHTR considers rupture of main primary piping as design basis accident in which animportant safety issue remains to be potential fuel and core graphite oxidation in case of significant air ingressinto the reactor core through the breached primary piping. The present study analyzes the air ingress behaviorand newly proposes a sustained counter-air diffusion (SCAD) mechanism for its practical prevention.
Kasuga, Shoji*; Kubota, Kenichi*; Okamoto, Futoshi*; Maekawa, Isamu*; Furihata, Noboru*; Saito, Masanao*; Kido, Yuji*; Ohashi, Hirofumi; Tachibana, Yukio; Kunitomi, Kazuhiko
no journal, ,
Conceptual design of a small-sized HTGR for electricity generation and district heating has been conducted by JAEA with support of Japanese vendors: Toshiba Corporation, Fuji Electric, Kawasaki Heavy Industries, Nuclear Fuel Industries, Shimizu Corporation, and Marubeni Utility Services. System design as well as nuclear design of the first core of HTR50S using the same CFPs as the HTTR has been performed and the nuclear design shows upgraded performance of the reactor compared with the HTTR.
Iwamoto, Osamu; Kunieda, Satoshi; Iwamoto, Nobuyuki; Minato, Futoshi; Okamoto, Tsutomu
no journal, ,
To extend the energy range of JENDL-4.0, nuclear data for neutron and proton induced reactions have been evaluated up to 200 MeV for medium-heavy nuclei. The nuclear reaction model calculation code CCONE, which was used for development of JENDL-4.0, was used. The code was upgraded on models for the pre-equilibrium process. The results improve consistency with the experimental data on particle emission spectra and isotope production cross sections. Evaluated results will be reported.
Kunieda, Satoshi; Iwamoto, Osamu; Iwamoto, Nobuyuki; Minato, Futoshi; Okamoto, Tsutomu; Sato, Tatsuhiko; Nakashima, Hiroshi; Iwamoto, Yosuke; Iwamoto, Hiroki; Kitatani, Fumito; et al.
no journal, ,
Neutron- and proton-induced evaluated nuclear data are required in a wide energy range for the design of accelerator applications. New evaluations are performed with recent progresses in the optical and pre-equilibrium model calculations. We also evaluated cross-sections for p + Li and p + 
Be which are highly requested from medical field. Our present high-energy nuclear data library, JENDL-4.0/HE, includes cross-sections for 132 nuclei up to 200 MeV. In this talk, we present the evaluation methods, evaluated double-differential cross-sections and results of benchmark calculations.
