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Teshigawara, Makoto; Tsuchikawa, Yusuke*; Ichikawa, Go*; Takata, Shinichi; Mishima, Kenji*; Harada, Masahide; Oi, Motoki; Kawamura, Yukihiko*; Kai, Tetsuya; Kawamura, Seiko; et al.
Nuclear Instruments and Methods in Physics Research A, 929, p.113 - 120, 2019/06
Times Cited Count：16 Percentile：86.05(Instruments & Instrumentation)A nano-diamond is an attractive neutron reflection material below cold neutron energy. The total neutron cross section of a nano-diamond was derived from a neutron transmission measurement over the neutron energy range of 0.2 meV to 100 meV because total neutron cross section data were not available. The total cross section of a nano-diamond with particle size of approximately 5 nm increased with a decrease in neutron energy to 0.2 meV. It was approximately two orders of magnitude larger than that of graphite at 0.2 meV. The contribution of inelastic scattering to the total cross section was to be shown negligible small at neutron energies of 1.2, 1.5, 1.9, 2.6, and 5.9 meV in the inelastic neutron scattering measurement. Moreover, small-angle neutron scattering measurements of the nano-diamond showed a large scattering cross section in the forward direction for low neutron energies.
Suzuki, Yoshio; Kawakami, Yoshiaki*; Nakajima, Norihiro
Mechanical Engineering Reviews, 4(1), p.15-00525_1 - 15-00525_18, 2017/01
The method to estimate errors included in observational data and the method to compare numerical results with observational results are investigated toward the verification and validation (V&V) of a seismic simulation. For the method to estimate errors, it is found that errors are caused by the resolution, the linearity, the temperature coefficient for sensitivity, the temperature coefficient for zero shift, the transverse sensitivity, the seismometer property, the aliasing, and so on. Thus, it is needed to estimate errors individually for those factors and integrate them. For the method to compare numerical results with observational results, it is found that six methods have been mainly proposed in existing researches. Evaluating those methods using nine items, advantages and disadvantages for those methods are arranged. The method is not well established so that it is necessary to employ those methods by compensating disadvantages and/or to search for a solution to a novel method.
Kadowaki, Haruhiko; Matsushima, Akira; Nakajima, Yoshiaki
Proceedings of 24th International Conference on Nuclear Engineering (ICONE-24) (DVD-ROM), 6 Pages, 2016/06
Advanced thermal reactor "FUGEN" is a heavy water-moderated boiling light water-cooled pressure tube-type reactor. Because tritium had been generated in the heavy water during the reactor operation, the heavy water system and helium system were contaminated by tritium. The chemical form of the tritium was water molecule in FUGEN. Air-through drying and vacuum drying were applied to the system drying, and it was demonstrated that both methods were effective for drying treatment of heavy water in system. Helium system, low-contamination and non inclusion, could finish the vacuum drying rapidly. However, Heavy water purification system needed long period for drying treatment. The result showed that it needed long period to dry up if the objects include the adsorbent of water such as alumina pellet, resin and silica gel. But it can be accelerated by replacement absorbed heavy water to light water from the result of drying treatment of the rotary type dehumidifier.
Nakajima, Norihiro; Suzuki, Yoshio; Miyamura, Hiroko; Nishida, Akemi; Kawakami, Yoshiaki; Guo, Z.; Tomiyama, Eiji*
Keisan Kogaku, 20(4), p.3338 - 3340, 2015/12
The issue 5 in the field 4 of "Monodukuri" in the HPCI strategy project is introduced. The title of the issue 5 is "research and development for the next-generation earthquake-resistant simulation of the large plants such as nuclear energy facilities". The illustration intends for a high temperature engineering examination research reactor. Implementation of FIESTA (Finite Element Analysis for Structure of Assembly) on K is described by reporting its efficiency and performance. To show a result of the numerical analysis, a visualization technique for the big data was described.
Nakajima, Norihiro; Nishida, Akemi; Kawakami, Yoshiaki; Suzuki, Yoshio; Matsukawa, Keisuke*; Oshima, Masami*; Izuchi, Hisao*
Transactions of 23rd International Conference on Structural Mechanics in Reactor Technology (SMiRT-23) (USB Flash Drive), 10 Pages, 2015/08
The digital shaking table is introduced to carry out numerical experiments for the so called STRUCTURE of a petroleum plant. In numerical experiments, STRUCTURE was precisely modelled as it is designed and meshed into fine finite elements. The components of STRUCTURE were meshed one by one, and the code of a finite element analysis for structure of assembly gathered every meshed components to run time domain response analysis. Four waves are applied to the analysis to determine its behaviour. Four waves are namely as El Centro, Taft, Hachinohe, and Geiyo. The results of experiments are discussed by comparing accumulating data in the past. It is concluded to reconfirm the methodology of gathering meshed components and a finite element analysis for structure of assembly with the STRUCTURE.
Nakajima, Norihiro; Miyamura, Hiroko; Kawakami, Yoshiaki; Kawamura, Takuma
Kashika Joho Gakkai-Shi, 35(Suppl.1), p.233 - 238, 2015/07
no abstracts in English
Nishida, Akemi; Nakajima, Norihiro; Kawakami, Yoshiaki; Iigaki, Kazuhiko; Sawa, Kazuhiro
Proceedings of 23rd International Conference on Nuclear Engineering (ICONE-23) (DVD-ROM), 7 Pages, 2015/05
The R&D on the three dimensional vibration simulation technologies for a nuclear facility is one of missions of Center for Computational Science and e-Systems, Japan Atomic Energy Agency. Until now, three dimensional building and equipment models of HTTR (High Temperature Engineering Test Reactor) have been constructed and been performed validation of the models by comparison with seismic observed records. In this report, the results obtained by seismic observation simulation on the Tohoku earthquake occurred in the 3/11/2011 using three dimensional models of the HTTR building are shown. The simulation results show good agreement with the real observation data.
Nakajima, Norihiro; Nishida, Akemi; Kawakami, Yoshiaki; Suzuki, Yoshio; Sawa, Kazuhiro; Iigaki, Kazuhiko
Proceedings of 23rd International Conference on Nuclear Engineering (ICONE-23) (DVD-ROM), 5 Pages, 2015/05
A numerical analysis controlling and managing system is implemented on K, which controls the modelling process and data treating, although the manager only controls a structural analysis by finite element method. The modeling process is described by the list of function ID and its procedures in a data base. The manager executes the process by order in the list for simulation procedures. The manager controls the intention of an analysis by changing the analytical process one to another. Experiments were carried out with static and dynamic analyses.
Nakajima, Norihiro; Nishida, Akemi; Kawakami, Yoshiaki; Suzuki, Yoshio
Nihon Kikai Gakkai Dai-24-Kai Sekkei Kogaku, Shisutemu Bumon Koenkai Koen Rombunshu (USB Flash Drive), 9 Pages, 2014/09
In this paper, a numerical analysis's controlling and managing system is suggested, which controls the modelling process and data treating for structural robustness, although a numerical analysis's manager only controls a structural analysis by finite element method. The modeling process is described by the list of function ID and its procedures in a data base. The analytical modeling manager executes the process by order of the lists for simulation procedures. The manager controls the intention of an analysis by changing the analytical process one to another. Modeling process was experimentally found that may subject to the intention of designing index. In the numerical experiments, K, supercomputer is utilized by using parallel computing resource with the controlling and managing system.
Nakajima, Norihiro; Nishida, Akemi; Kawakami, Yoshiaki; Okada, Tatsuo*; Tsuruta, Osamu*; Sawa, Kazuhiro; Iigaki, Kazuhiko
Proceedings of 22nd International Conference on Nuclear Engineering (ICONE-22) (DVD-ROM), 9 Pages, 2014/07
Almost all industrial products are assembled from multiple parts. A nuclear facility is a large structure consisting of more than 10 million components. This paper discusses a method to analyze an assembly by gathering data on its component parts. Gathered data on component may identify ill conditioned meshes for connecting surfaces between components. These ill meshes are typified by nodal point disagreement in finite element discretization. A technique to resolve inconsistencies in data among the components is developed. By using this technique, structural analysis for an assembly can be carried out, and results can be obtained by the use of supercomputers, such as the K computer. Numerical results are discussed for components of the High Temperature Engineering Test Reactor.
Nakajima, Norihiro; Nishida, Akemi; Kawakami, Yoshiaki; Okada, Tatsuo; Tsuruta, Osamu; Sawa, Kazuhiro; Iigaki, Kazuhiko
Tabo Kikai, 42(5), p.332 - 338, 2014/05
K computer is one of the highest performance computers in the world. This paper discusses one of R&D issues in K computer national project. Industrial products are an artifact, which are assembly consisting of simple components more than at least two regardless of the big products and small products. In the nuclear industry, the facilities are large structures consisting of over 10 millions of components, since they are engaged with the highest technology and for safety sake. This paper introduces a method to analyze an assembly by gathering its components data. In the manner of gathering components data, it is raised many issues to concern among components. It is developed a technique to solve the inconsistent data among the components. By using this technique, a structural analysis for an assembly is done by using K computer. Numerical results are presented in the case of analysis for High Temperature engineering Test Reactor's components.
Yamane, Yuichi; Nakajima, Ken*; Abe, Hitoshi; Hayashi, Yoshiaki*; Arisawa, Jun*; Hayami, Satoru*
Nihon Genshiryoku Gakkai Wabun Rombunshi, 9(1), p.96 - 107, 2010/03
A special committee of "Research on the analysis methods for accident consequence of nuclear fuel facilities (NFF)" was organized by the AESJ under the entrustment of JAEA, which aims to research on the state-of-the-art of consequence analysis method for PSA of NFF such as fuel reprocessing and fuel fabrication facilities. Its research activities were focused on the analysis method of consequence for postulated accidents with potentially large consequence, e.g. events of criticality, spill of molten glass, hydrogen explosion, boiling of radioactive solution and fire, resulting in release of radioactive material to the environment. The research results were summarized in a series of six reports. In this report, the evaluation methods of criticality accident, such as simplified methods, one-point reactor kinetics codes and quasi-static method, were investigated and their features were summarized to provide useful information for the safety evaluation of nuclear fuel facilities.
Osaka, Masahiko; Serizawa, Hiroyuki; Kato, Masato; Nakajima, Kunihisa; Tachi, Yoshiaki; Kitamura, Ryoichi; Miwa, Shuhei; Iwai, Takashi; Tanaka, Kenya; Inoue, Masaki; et al.
Journal of Nuclear Science and Technology, 44(3), p.309 - 316, 2007/03
Times Cited Count：30 Percentile：87.22(Nuclear Science & Technology)no abstracts in English
Osaka, Masahiko; Serizawa, Hiroyuki*; Kato, Masato; Inoue, Masaki; Nakajima, Kunihisa*; Tachi, Yoshiaki; Kitamura, Ryoichi; Oki, Shigeo; Miwa, Shuhei; Iwai, Takashi*; et al.
Proceedings of International Conference on Nuclear Energy System for Future Generation and Global Sustainability (GLOBAL 2005) (CD-ROM), 6 Pages, 2005/10
Development of minor actinide containing fuel/target, i.e., (Pu,Am)O
-MgO, (Pu,Np)O-MgO, (U,Pu,Np)O, (U,Pu,Np)N and (Pu,Np,Zr)N, for the use in a future integrated system of fast reactor and accelerator driven system is underway as a collaborative work between JAERI and JNC. The present statuses of fabrication test and property measurements are given. Irradiation test in the experimental fast reactor JOYO is also mentioned.
O
Hata, Yoshiaki; Kita, Eiji*; Kagomiya, Isao*; Kay, Kohn*; Shiratori, Kiichi*; Nakajima, Kenji*; Kakurai, Kazuhisa*
Journal of the Physical Society of Japan, Vol.70, Supplement A, p.195 - 196, 2001/05
no abstracts in English
Fujita, Mitsutane*; Kinugawa, Junichi*; Tsuji, Hirokazu; Kaji, Yoshiyuki; Tachi, Yoshiaki*; Saito, Junichi*; Shimura, Kazuki*; Nakajima, Ritsuko*; Iwata, Shuichi*
Fusion Engineering and Design, 51-52, p.769 - 774, 2000/11
Times Cited Count：1 Percentile：12.1(Nuclear Science & Technology)no abstracts in English
Kinugawa, Junichi*; Fujita, Mitsutane*; Noda, Tetsuji*; Tsuji, Hirokazu; Kaji, Yoshiyuki; Sakino, Takao*; Tachi, Yoshiaki*; Kaneda, Kenichiro*; Mashiko, Shinichi*; Shimura, Kazuki*; et al.
Proceedings of 9th German-Japanese Workshop on Chemical Information, p.134 - 135, 2000/00
no abstracts in English
Kaji, Yoshiyuki; Tsuji, Hirokazu; Sakino, Takao*; Fujita, Mitsutane*; Kinugawa, Junichi*; Tachi, Yoshiaki*; Saito, Junichi*; Kano, Shigeki*; Shimura, Kazuki*; Nakajima, Ritsuko*; et al.
JAERI-Tech 99-007, 32 Pages, 1999/02
no abstracts in English
Tsuji, Hirokazu; ; Fujita, Mitsutane*; Kano, Shigeki*; Tachi, Yoshiaki*; Shimura, Kazuki*; Nakajima, Ritsuko*; Iwata, Shuichi*
Advances in Science and Technology, 24, p.417 - 424, 1999/00
no abstracts in English
Tsuji, Hirokazu; ; Fujita, Mitsutane*; Kurihara, Yutaka*; Kano, Shigeki*; Tachi, Yoshiaki*; Shimura, Kazuki*; Nakajima, Ritsuko*; Iwata, Shuichi*
Journal of Nuclear Materials, 271-272, p.486 - 490, 1999/00
no abstracts in English
