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Isaka, Koji; Suwa, Masayuki; Kimura, Kazuya; Suzuki, Makoto; Ikekame, Yoshinori; Nagadomi, Hideki
JAEA-Technology 2021-039, 48 Pages, 2023/02
JRR-3 Process control system is used from the initial criticality (1990) after remodeling JRR- 3 as equipment used for monitoring and control of flow rate, temperature, pressure, water level, etc. of coolant and operation of nuclear reactor equipment, and it became necessary to renew as the aging progressed and spare parts could not be obtained sufficiently. Upon renewal, from the viewpoint of ensuring conservation of the core such as decay heat removal and minimizing the impact on reactor users and minimizing costs, it is important not to stop long-term reactor shutdown we planned to divide it into three stages and make it on a continuous basis. This report summarizes the renewal plan and renewal work divided into three stages.
Yonomoto, Taisuke; Nakashima, Hiroshi*; Sono, Hiroki; Kishimoto, Katsumi; Izawa, Kazuhiko; Kinase, Masami; Osa, Akihiko; Ogawa, Kazuhiko; Horiguchi, Hironori; Inoi, Hiroyuki; et al.
JAEA-Review 2020-056, 51 Pages, 2021/03
A group named as "The group for investigation of reasonable safety assurance based on graded approach", which consists of about 10 staffs from Sector of Nuclear Science Research, Safety and Nuclear Security Administration Department, departments for management of nuclear facility, Sector of Nuclear Safety Research and Emergency Preparedness, aims to realize effective graded approach (GA) about management of facilities and regulatory compliance of JAEA. The group started its activities in September, 2019 and has had discussions through 10 meetings and email communications. In the meetings, basic ideas of GA, status of compliance with new regulatory standards at each facility, new inspection system, etc were discussed, while individual investigation at each facility were shared among the members. This report is compiled with expectation that it will help promote rational and effective safety management based on GA by sharing contents of the activity widely inside and outside JAEA.
Sakaki, Hironao; Nishiuchi, Mamiko; Maeda, Shota; Sagisaka, Akito; Pirozhkov, A. S.; Pikuz, T.; Faenov, A.*; Ogura, Koichi; Fukami, Tomoyo; Matsukawa, Kenya*; et al.
Review of Scientific Instruments, 85(2), p.02A705_1 - 02A705_4, 2014/02
Times Cited Count:2 Percentile:11.15(Instruments & Instrumentation)High intensity laser-plasma interaction has attracted considerable interest for a number of years. The laser-plasma interaction is accompanied by generation of various charged particle beams. Results of simultaneous novel measurements of electron-induced photonuclear neutrons (photoneutron), which are a diagnostic of the laser-plasma interaction, are proposed to use for optimization of the laser-plasma ion generation. The proposed method is demonstrated by the laser irradiation with the intensity os 110 W/cm on the metal foil target. The photoneutrons are measured by using NE213 liquid scintillation detectors. Heavy-ion signal is registered with the CR39 track detector simultaneously. The measured signals of the electron-induced photoneutrons are well reproduced by using the Particle and Heavy Ion Transport code System (PHITS). The results obtained provide useful approach for analyzing the various laser based ion beams.
Suwa, Masayuki; Isaka, Koji; Ouchi, Satoshi; Goto, Shingo; Ikekame, Yoshinori; Terakado, Yoshibumi
JAEA-Technology 2011-041, 35 Pages, 2012/03
JRR-3 process control computer system is used to monitor and control various process parameters such as flow rates, temperatures, pressures and so on, and operate many reactor components such as cooling pumps and valves. The system has been under aging degradation at this time and the renewal of the system has become indispensable. The renewal work has planned, paying a due consideration to minimizing renewal costs and duration, to be separated in three stages. This paper describes the renewal plan and renewal works of main part of the system.
Ouchi, Satoshi; Suwa, Masayuki; Isaka, Koji; Ikekame, Yoshinori; Terakado, Yoshibumi
JAEA-Testing 2011-006, 43 Pages, 2012/02
JRR-3 has been utilized for various researches such as neutron irradiation experiment, neutron beam experiment and so on as a high performance research reactor with thermal power of 20 MW since the first criticality in March, 1990. Process data needed for JRR-3 operation such as temperatures, pressures, and flow rates, etc. had been processed by JRR-3 process computer system which consisted of several computer systems and several application softwares. The system needed complicated data administration and conservation. Also there was a problem in the administration of recording data. Data discrepancy among computers used in the system was taken place since the system was not so designed as to synchronize the process timing among the computers. Therefore, we developed a program to synchronize among all of the computers. This paper reports the development of data processing computer system.
Sakaki, Hironao; Nishiuchi, Mamiko; Hori, Toshihiko; Bolton, P.; Yogo, Akifumi; Katagiri, Masaki*; Ogura, Koichi; Sagisaka, Akito; Pirozhkov, A. S.; Orimo, Satoshi; et al.
Applied Physics Express, 3(12), p.126401_1 - 126401_3, 2010/11
Times Cited Count:8 Percentile:34.3(Physics, Applied)Many applications of laser-accelerated ions will require beamlines with diagnostic capability for validating simulations and machine performance at the single bunch level as well as for the development of controls to optimize machine performance. We demonstrated prompt, in-line, single bunch transverse profile and energy spectrum detection using a thin luminescent diagnostic and scintillator-based time-of-flight spectrometer simultaneously. The Monte Carlo code, particle and heavy ion transport code systems (PHITS) simulation is shown to be reasonably predictive at low proton energy for the observed transverse profiles measured by the thin luminescent monitor and also for single bunch energy spectra measured by time-of-flight spectrometry.
Isaka, Koji; Terunuma, Noriaki; Ouchi, Satoshi; Oki, Keiichi; Suwa, Masayuki
Nihon Hozen Gakkai Dai-6-Kai Gakujutsu Koenkai Yoshishu, p.279 - 282, 2009/08
As the modified JRR-3 has been operated for 18 years, it is necessary to be maintained for keeping the safe and stable operation. The review of maintenance activity is constantly performed for the step-by-step update of facilities and the improvement of the maintenance method and so on. Our investigation of the maintenance activity about the instrumentation and control device of modified JRR-3 is presented.
Suwa, Masayuki; Isaka, Koji; Ouchi, Satoshi; Terunuma, Noriaki
UTNL-R-0471, p.12_1_1 - 12_1_8, 2009/03
no abstracts in English
Ikekame, Yoshinori; Ouchi, Satoshi; Suwa, Masayuki; Isaka, Koji; Goto, Shingo; Murayama, Yoji
JAEA-Technology 2007-052, 47 Pages, 2007/08
In order to sustain safe and stable operation of JRR-3, it is necessary to measure and indicate appropriately the process values such as flow rate of coolant with the process instrumentation facilities of JRR-3. Whenever reactor facilities such as cooling pump or measuring device are maintained or refurbished, the process instrumentation facilities are calibrated with the appropriate criteria established by considering overall accuracy of the facilities. In this report, for all of the safety protection system, a part of the process instrumentation facilities, accuracy of each component and overall accuracy of the system are compiled. Using these date, the process instrumentation facilities would be maintained more effectively and objectively.
Hayashi, Yukio; Fukumi, Atsushi*; Matsukado, Koji*; Mori, Michiaki; Kotaki, Hideyuki; Kando, Masaki; Chen, L.-M.; Daito, Izuru; Kondo, Shuji; Kanazawa, Shuhei; et al.
Radiation Protection Dosimetry, 121(2), p.99 - 107, 2006/12
Times Cited Count:16 Percentile:72.68(Environmental Sciences)The authors obtain a new equation to estimate the forward component of a photon dose which is generated through the interaction between a target and a short pulse high power laser. As the equation is quite simple, it is useful for calculating the photon dose. The equation shows that the photon dose is proportional to the electron temperature for the range of its temperature 3 MeV, and proportional to square of the electron temperature for the range of its temperature 3 MeV. The dose estimated with this method is roughly consistent with the result of Monte Carlo simulation. On someassumptions and corrections, it can reproduce experimental results obtained and the dose result calculated at other laboratories.
Nakabayashi, Hiroki; Kurisaka, Kenichi; Sato, Koji; Niwa, Hajime; Aoki, Kazuo*
JAEA-Technology 2006-027, 119 Pages, 2006/03
This report describes a study about the criticality safety design for the large-scale electrorefiner, which is designed in the activities of "The Design Study of Metal Fuel Recycle System (2002)", under the collaboration with Central Research Institute of Electric Power Industry, and the continuation of "A Study of the Criticality Safety Design for the Metal Fuel Recycle System", which was published at September 2003. The report includes a detail design and quantitative criticality parameter limits based on "the mass control supported with chemical form control" concept which is proposed in "A Study of the Criticality Safety Design for the Metal Fuel Recycle System". Furthermore procedures to determine these limits are presented in the report. Next we studied contingencies anticipated under the critical control and executed quantitative criticality safety analyses of models based on these abnormal conditions. The analytical result shows adequate safety margins are existed in the criticality safety design even if many of these contingencies could occur. Moreover we propose a concept of material transfer and production control system, we call it as "Operation by wire", which all equipment and handling machines are electrified and the control system provides completely automated process control and operation. The control system eliminates human errors and violations like over batching error or transfer error in the commercial scale metal fuel recycle system with complicated operation procedures.
Sagisaka, Akito; Daido, Hiroyuki; Ogura, Koichi; Orimo, Satoshi; Hayashi, Yukio; Nishiuchi, Mamiko; Mori, Michiaki; Matsukado, Koji*; Fukumi, Atsushi*; Li, Z.*; et al.
Applied Physics B, 78(7-8), p.919 - 922, 2004/05
Times Cited Count:26 Percentile:71.22(Optics)no abstracts in English
Nio, Daisuke; Ikekame, Yoshinori; Suwa, Masayuki; Isaka, Koji; Ouchi, Satoshi; Mineshima, Hiromi; Motohashi, Jun; Torii, Yoshiya; Kinase, Masami; Murayama, Yoji
no journal, ,
no abstracts in English
Niwa, Hajime; Kurisaka, Kenichi; Sato, Ikken; Tobita, Yoshiharu; Kamiyama, Kenji; Yamano, Hidemasa; Miyahara, Shinya; Ohno, Shuji; Seino, Hiroshi; Ishikawa, Hiroyasu; et al.
no journal, ,
In order to develop the core damage evaluation technology (level 2 PSA) for sodium-cooled fast reactors, we develop the new analysis codes of post accident material relocation phase and of ex-vessel events, and we develop the technical bases that is necessary for level 2 PSA. In this presentation, summary and scope of the entire study is introduced as a part of the 4 series presentations.
Nakai, Ryodai; Kurisaka, Kenichi; Sato, Ikken; Tobita, Yoshiharu; Kamiyama, Kenji; Yamano, Hidemasa; Miyahara, Shinya; Ohno, Shuji; Seino, Hiroshi; Ishikawa, Hiroyasu; et al.
no journal, ,
To develop a core damage evaluation technology (level-2 PSA) in sodium-cooled fast reactors, a new analysis method is developed for core-material relocation phase and internal containment vessel event. This study also develop technical basis necessary for the level-2 PSA.
Suwa, Masayuki; Terunuma, Noriaki; Isaka, Koji; Ouchi, Satoshi; Ikekame, Yoshinori
no journal, ,
no abstracts in English
Ueno, Hiroki; Kawakita, Yukinobu; Ohara, Koji*; Shimakura, Hironori; Tahara, Shuta*; Kumara, L. S. R.*; Yamaguchi, Hiroshi*; Yasunaga, Akinori*; Wakisaka, Yuiko*; Ito, Masayoshi*; et al.
no journal, ,
Bi-Zn system has a phase diagram with a miscibility gap where critical point is at BiZn. It is known that concentration fluctuation increases on approaching to the miscibility gap. Earlier studies suggested that the miscibility gap is attributed to difference in atomic size between Bi and Zn. Recent developments of instrument and analysis technique enable us to deduce partial structures and demonstrate atomic configurations in liquid. We performed detailed analysis on medium-range structure in liquid BiZn by using neutron diffraction data obtained by the two-axis diffractometer, HERMES, installed in JRR-3M, JAEA and, X-ray diffraction at BL08W beamline in SPring-8, Hyogo, Japan. 3D atomic structural model obtained by Revere Monte Carlo technique exhibits temperature evolution of concentration fluctuations in medium-range structure, which suggests that phase separation tendency appears even in the edge of the miscibility gap of liquid Bi-Zn.
Shimakura, Hironori; Kawakita, Yukinobu; Ohara, Koji*; Wakisaka, Yuiko*; Kohara, Shinji*; Takeda, Shinichi*
no journal, ,
no abstracts in English
Sagisaka, Akito; Ogura, Koichi; Nishikino, Masaharu; Pirozhkov, A. S.; Kawachi, Tetsuya; Nishiuchi, Mamiko; Kando, Masaki; Kondo, Kiminori; Arikawa, Yasunobu*; Kojima, Sadaoki*; et al.
no journal, ,
High-intensity laser and thin-foil interactions produce high-energy particles and hard X-ray. A proton beam driven by a high-intensity laser has received attention as a ion source for medical and other applications. We have performed high energy laser-matter interaction experiments using a thin-foil target irradiated by LFEX laser at Osaka University. The three beams were focused at a thin-foil target. The maximum proton energy of 40 MeV energy were observed at the total laser energy of 700 J. The preliminary experiment for plasma mirror are started.
Sagisaka, Akito; Ogura, Koichi; Pirozhkov, A. S.; Nishikino, Masaharu; Kon, Akira; Nishiuchi, Mamiko; Esirkepov, T. Z.; Kando, Masaki; Kawachi, Tetsuya; Kondo, Kiminori; et al.
no journal, ,
High-intensity laser and thin-foil interactions produce high-energy particles and hard X-ray. A proton beam driven by a high-intensity laser has received attention as a ion source for medical and other applications. We have performed high energy laser-matter interaction experiments using a thin-foil target irradiated by LFEX laser at Osaka University. The three beams were focused at a thin-foil target. The maximum proton energy of 40 MeV energy were observed at the total laser energy of 1 kJ. The proton acceleration experiment with plasma mirror are started.