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Asakura, Kazuki; Shimomura, Yusuke; Donomae, Yasushi; Abe, Kazuyuki; Kitamura, Ryoichi; Miyakoshi, Hiroyuki; Takamatsu, Misao; Sakamoto, Naoki; Isozaki, Ryosuke; Onishi, Takashi; et al.
JAEA-Review 2021-020, 42 Pages, 2021/10
The disposal of radioactive waste from the research facility need to calculate from the radioactivity concentration that based on variously nuclear fuels and materials. In Japan Atomic Energy Agency Oarai Research and Development Institute, the study on considering disposal is being advanced among the facilities which generate radioactive waste as well as the facilities which process radioactive waste. This report summarizes a study result in FY2020 about the evaluation method to determine the radioactivity concentration in radioactive waste on Oarai Research and Development Institute.
Wakai, Takashi; Machida, Hideo*; Arakawa, Manabu*; Yanagihara, Seiji*; Suzuki, Ryosuke*; Matsubara, Masaaki*
Proceedings of 26th International Conference on Nuclear Engineering (ICONE-26) (Internet), 9 Pages, 2018/07
This paper studies crack opening displacement (COD) evaluation methods used in Leak-Before-Break (LBB) assessment of Sodium cooled Fast Reactor (SFR) pipe. For SFR pipe, the continuous leak monitoring will be adopted as an alternative to a volumetric test of the weld joints under conditions that satisfy LBB. The sodium pipes are made of ASME Gr.91 (modified 9Cr-1Mo steel). Thickness of the pipes is small, because the internal pressure is very small. Modified 9Cr-1Mo steel has a relatively large yield stress and small work hardening coefficient comparing to the austenitic stainless steels which are currently used in the conventional plants. In order to assess the LBB behavior of the sodium pipes made of modified 9Cr-1Mo steel, the coolant leak rate from a through wall crack must be estimated properly. Since the leak rate is strongly related to the crack opening displacement (COD), an appropriate COD assessment method must be established to perform LBB assessment. However, COD assessment method applicable for SFR pipes - having thin wall thickness and made of small work hardening material - has not been proposed yet. Thus, a COD assessment method applicable to such a pipe was proposed in this study. In this method, COD was calculated by classifying the components of COD; elastic, local plastic and fully plastic. In addition, the verification of this method was performed by comparing with the results of a series of four-point bending tests using modified 9Cr-1Mo steel pipe having a circumferential through wall notch. As a result, in some cases, COD were over-estimated especially for large cracks. Although the elastic component of COD is still over-estimated for large cracks, leak evaluation from small cracks is much more important in LBB assessment. Therefore, this study recommends that only the elastic component of COD should be adopted in LBB assessment of SFR pipes.
Suzuki, Ryosuke*; Matsubara, Masaaki*; Sakamoto, Kenji*; Suzuki, Masato*; Shiraishi, Taisuke*; Yanagihara, Seiji*; Izawa, Satoru*; Wakai, Takashi
Experimental Techniques, 40(1), p.253 - 260, 2016/09
Times Cited Count:0 Percentile:0.00(Engineering, Mechanical)The plastic collapse behavior and strength were investigated for an austenitic stainless steel pipe with two 90 through-wall notches perpendicular to the pipe axis direction. Double-notch specimens with various notch separation distances were coated with photo-plastic film. Arbitrary combined axial tensile and bending loads were applied to the specimens. Changes in the photo-plastic fringe pattern were observed during the tests to investigate the plastic collapse behavior. The plastic collapse strength was evaluated using a model based on an elastic-perfectly plastic body. The photo-plastic fringe patterns at the experimental plastic collapse point differed based on the loading history. Thus, the plastic collapse behavior depends on the loading history. In addition, the plastic collapse strength differed based on the loading history and hardly depended on the notch separation distance. The experimental plastic collapse occurred before reaching the theoretical plastic point for only some pure-tension loading tests. Thus, the model analysis based on an elastic-perfectly plastic body used in this study might give an unconservative estimate for the plastic collapse of a stainless steel pipe subjected to a pure tension load.
Suzuki, Ryosuke*; Matsubara, Masaaki*; Yanagihara, Seiji*; Morijiri, Mitsugu*; Omori, Atsushi*; Wakai, Takashi
Procedia Materials Science, 12, p.24 - 29, 2016/00
Times Cited Count:2 Percentile:72.79(Engineering, Mechanical)In this study, the plastic collapse strength of asymmetry multiple circumferential notched stainless steel pipes subjected to combined axial tension and bending is investigated experimentally and is compared with the theoretical plastic collapse strength. In addition, the potential is discussed for the simplification of structural integrity evaluation of multiple cracked piping. The integrity of the asymmetry multiple circumferential notched stainless steel pipes subjected to combined axial tension and bending can be evaluated conservatively using the theoretical plastic collapse strength for the pipe with multiple notches calculated based on the elastic-perfectly plastic model.
Wakai, Takashi; Machida, Hideo*; Yoshida, Shinji*; Yanagihara, Seiji*; Suzuki, Ryosuke*; Matsubara, Masaaki*; Enuma, Yasuhiro
Engineering Failure Analysis, 56, p.484 - 500, 2015/10
Times Cited Count:1 Percentile:11.26(Engineering, Mechanical)Ajimura, Shuhei*; Bezerra, T. J. C.*; Chauveau, E.*; Enomoto, T.*; Furuta, Hisataka*; Harada, Masahide; Hasegawa, Shoichi; Hiraiwa, T.*; Igarashi, Yoichi*; Iwai, Eito*; et al.
Progress of Theoretical and Experimental Physics (Internet), 2015(6), p.063C01_1 - 063C01_19, 2015/06
Times Cited Count:6 Percentile:43.98(Physics, Multidisciplinary)The J-PARC E56 experiment aims to search for sterile neutrinos at the J-PARC Materials and Life Science Experimental Facility (MLF). In order to examine the feasibility of the experiment, we measured the background rates of different detector candidate sites, which are located at the third floor of the MLF, using a detector consisting of plastic scintillators with a fiducial mass of 500 kg. The gammas and neutrons induced by the beam as well as the backgrounds from the cosmic rays were measured, and the results are described in this article.
Yanagihara, Seiji*; Matsubara, Masaaki*; Suzuki, Ryosuke*; Suzuki, Masato*; Shiraishi, Taisuke*; Sakamoto, Kenji*; Wakai, Takashi
Nihon Kikai Gakkai M&M 2012 Zairyo Rikigaku Kanfuarensu Koen Rombunshu (CD-ROM), 2 Pages, 2012/09
Shiraishi, Taisuke*; Matsubara, Masaaki*; Suzuki, Ryosuke*; Suzuki, Masato*; Yanagihara, Seiji*; Sakamoto, Kenji*; Wakai, Takashi
Nihon Kikai Gakkai M&M 2012 Zairyo Rikigaku Kanfuarensu Koen Rombunshu (CD-ROM), 3 Pages, 2012/09
Shiraishi, Taisuke*; Matsubara, Masaaki*; Suzuki, Ryosuke*; Suzuki, Masato*; Wakai, Takashi; Sakamoto, Kenji*
Proceedings of 5th International Workshop New Methods of Damage and Failure Analysis of Structural Parts (CD-ROM), 6 Pages, 2012/09
Seki, Ryosuke*; Matsumoto, Yutaka*; Suzuki, Yasuhiro*; Watanabe, Kiyomasa*; Hamamatsu, Kiyotaka; Itagaki, Masafumi*
Plasma and Fusion Research (Internet), 5, p.014_1 - 014_3, 2010/06
no abstracts in English
Kadono, Ryosuke*; Sato, Koki*; Koda, Akihiro*; Nagata, Takashi*; Furukawa, Hazuki*; Suzuki, Junichi; Matsuda, Masaaki; Oishi, Kazuki; Higemoto, Wataru; Kuroiwa, Sogo*; et al.
Physical Review B, 74(2), p.024513_1 - 024513_5, 2006/07
Times Cited Count:10 Percentile:43.59(Materials Science, Multidisciplinary)The response of vortex state to the magnetic field in NbSn is probed using muon spin rotation and small-angle neutron scattering. A transformation of vortex structure between hexagonal and squared lattice is observed over a relatively low field range of 2-3T. The gradual increase of the magnetic penetration depth with increasing field provides microscopic evidence for anisotropic (or multigapped) -wave pairing suggested by the Raman scattering experiment. This result renders need for careful examination on the difference of electronic properties between NbSn and VSi.
Shimomura, Koichiro*; Kadono, Ryosuke*; Nishiyama, Kusuo*; Watanabe, Isao*; Suzuki, Takao*; Pratt, F.*; Oishi, Kazuki; Mizuta, Masashi*; Saito, Mineo*; Chow, K. H.*; et al.
Physica B; Condensed Matter, 376-377, p.444 - 446, 2006/04
Times Cited Count:1 Percentile:6.21(Physics, Condensed Matter)Yoshikawa, Shinji; YOSHIKAWA JNC, Shinji; Suzuki, Ryosuke*; kondo, koki*; Nakai, Satoshi*; NAKAI, Satoshi*
The 23rd International Conference on Termoelectric, 0 Pages, 2004/12
A prototype system for thermoelectric power generation using the Heusler Fe2 VAI alloy has been studied as a potential heat recovery system from a liquid metal cooled fast breeder reactor. The modules consisting of 180 pairs using Fe2VAi cast alloy were mouted on 1.8 m long of the outer surface of a stainless tube (O.D. 34mm) which is internally heated by flowing liquid sodium (484-670K, 2-8 1/min). The element has a shape of a long cuboid, where one small rectangular end was thermally contacted with the tube surface and the other end was directly cooled by forced air flow to form a counter-type heat exchanger. The internal electric resistances of the modules were nearly same, however, the electromotive force varied widely because of the difference of thermal resistance between the module and tube surface. The output power generated from this prototype system was evaluated to be about 4.2 W/m assuming that all the circumference of the pipe surface is covered by the elements.
Suzuki, Ryosuke*; Tanabe, Kentaro*; kondo, koki*; Ono, Katsutoshi*; Toda, Shinichi; Kasagawa, Yusuke; Tamayama, Kiyoshi; Oketani, Kazuhiro*
JNC TY4400 2003-004, 214 Pages, 2003/08
Recently, it has been important to reuse discharged heat energy from present nuclear plants in the view of reduction of environmental burden and improvement of heat efficiency for plant. For practical use in future of sodium cooled FBRs, which are typical high temperature system, this issue must be given priority. The thermal electric conversion system has been applied to the limited uses such as space or military, however, that results show good merits for reliability, maintenance free, and so on. Recently, this technology has been reconsidered in the view of saving energy in general industry. In this study, we made an investigation for applicability of the thermal electric conversion system to sodium cooled FBR as a heat recovery techbnology. Exactly, We have carried out the fundamental research and development for thermoelectric materials and elements, development of modules, and sodium tests with those modules, and then, we acquired the fundamental knowledge to estimate the efficiencies of thermal electric conversion system or modules for a sodium cooled FBR.
Sawahata, Satoshi; Tamaoki, Yuichi; Isozaki, Ryosuke; Suzuki, Ryuta; Akada, Masataka; Suzuki, Hisashi; Yonezawa, Ryoma; Fujishima, Tadatsune; Mizukoshi, Yasutaka; Sakamoto, Naoki
no journal, ,
no abstracts in English
Yamanishi, Takeshi; Sekiya, Yoshitomo; Suzuki, Tatsuya; Ito, Seiji; Kitagawa, Yoshito*; Hagihara, Takeshi*; Doi, Takashi*; Saito, Ryosuke*
no journal, ,
no abstracts in English
Nakatani, Takeshi; Inamura, Yasuhiro; Ito, Takayoshi; Kajimoto, Ryoichi; Aoyagi, Tetsuo; Ohara, Takashi; Otomo, Toshiya*; Yasu, Yoshiji*; Suzuki, Jiro*; Morishima, Takahiro*; et al.
no journal, ,
We have started the commissioning of the neutron scattering experiment instruments since May 2008 in MLF, J-PARC. Simultaneously, we have started the commissioning of the data acquisition and analysis software. Experimental users operate this software through the software framework which we have developed. The software framework was developed based on Python which is an object oriented script language. The system implemented with the software framework can seamlessly measure, analyze and visualize with some modules which are experimental control and data analysis. In this presentation, we report the process of the construction and the current status of the software.
Yamanishi, Takeshi; Sekiya, Yoshitomo; Suzuki, Tatsuya; Kitagawa, Yoshito*; Saito, Ryosuke*; Yokota, Daisuke*
no journal, ,
no abstracts in English
Yamanishi, Takeshi; Sekiya, Yoshitomo; Suzuki, Tatsuya; Kitagawa, Yoshito*; Kato, Kinya*; Saito, Ryosuke*
no journal, ,
no abstracts in English
Suzuki, Seima; Otaka, Hikaru; Usui, Yasufumi*; Morigaki, Yoshin*; Ito, Ryosuke*
no journal, ,
no abstracts in English