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Eguchi, Shohei; Shibata, Hiroshi; Imaizumi, Tomomi; Nagata, Hiroshi; Tanimoto, Masataka; Kusunoki, Tsuyoshi
JAEA-Review 2017-032, 26 Pages, 2018/02
JAEA-Review-2017-032.pdf:2.44MB
A practical training course using the JMTR and other research infrastructures was held from July 24th to August 4th in 2017 for Asian young researchers and engineers. This course was adopted as Japan-Asia Youth Exchange Program in Science (SAKURA Exchange Program in Science) which is the project of the Japan Science and Technology Agency, and this course aims to enlarge the number of high-level nuclear researchers/engineers in Asian countries which are planning to introduce a nuclear power plant, and to promote the use of facilities in future. In this year, 10 young researchers and engineers joined the course from 6 countries. This course consists of lectures, which are related to irradiation test research, safety management of nuclear reactors, nuclear characteristics of the nuclear reactors, etc., practical training such as practice of research reactor operation using simulator and technical tour of nuclear facilities on nuclear energy. The content of this course in FY 2017 is reported in this paper.
Takemoto, Noriyuki; Imaizumi, Tomomi; Kimura, Nobuaki; Tsuchiya, Kunihiko; Hori, Junichi*; Sano, Tadafumi*; Nakajima, Ken*
Proceedings of International Conference on the Physics of Reactors; The Role of Reactor Physics toward a Sustainable Future (PHYSOR 2014) (CD-ROM), 11 Pages, 2014/09
Neutronic evaluations in JMTR have been performed for irradiation tests by Monte Carlo method with thermal neutron scattering law, S(
, 
), data for beryllium metal, etc. The calculation accuracy of fast and thermal neutron fluxes are 
10% and 30%, respectively. Analytical and experimental investigations to achieve higher calculation accuracy, especially for the thermal neutron flux up to the fast neutron flux level, have been therefore performed to offer higher value data technically to the JMTR users. In order to investigate an effect of fabrication method of beryllium material on the calculation accuracy, total cross-sections of beryllium specimens were measured using KURRI-LINAC, and it was found that the total cross-section was different from the theoretical one, and depended on the crystal texture, etc. The S(, ) was adjusted based on the measured data, and the applicability to the neutronic evaluation in the JMTR was verified.
Watahiki, Shunsuke; Hanakawa, Hiroki; Imaizumi, Tomomi; Nagata, Hiroshi; Ide, Hiroshi; Komukai, Bunsaku; Kimura, Nobuaki; Miyauchi, Masaru; Ito, Masayasu; Nishikata, Kaori; et al.
JAEA-Technology 2013-021, 43 Pages, 2013/07
JAEA-Technology-2013-021.pdf:5.12MB
The number of research reactors in the world is decreasing because of their aging. On the other hand, the necessity of research reactor, which is used for human resources development, progress of the science and technology, industrial use and safety research is increasing for the countries which are planning to introduce the nuclear power plants. From above background, the Neutron Irradiation and Testing Reactor Center began to discuss a basic concept of Multipurpose Compact Research Reactor (MCRR) for education and training, etc., on 2010 to 2012. This activity is also expected to contribute to design tool improvement and human resource development in the center. In 2011, design study of reactor core, irradiation facilities with high versatility and practicality, and hot laboratory equipment for the production of Mo-99 was carried out. As the result of design study of reactor core, subcriticality and operation time of the reactor in consideration of an irradiation capsule, and about the transient response of the reactor to the reactivity disturbance during automatic control operation, it was possible to do automatic operation of MCRR, was confirmed. As the result of design study of irradiation facilities, it was confirmed that the implementation of an efficient mass production radioisotope Mo-99 can be expected. As the result of design study with hot laboratory facilities, Mo-99 production, RI export devised considered cell and facilities for exporting the specimens quickly was designed.
Imaizumi, Tomomi; Ide, Hiroshi; Naka, Michihiro; Komukai, Bunsaku; Nagao, Yoshiharu
UTNL-R-0483, p.10_2_1 - 10_2_8, 2013/03
no abstracts in English
Park, C.; Tanimoto, Masataka; Imaizumi, Tomomi; Miyauchi, Masaru; Ito, Masayasu; Kaminaga, Masanori
JAEA-Technology 2012-039, 87 Pages, 2013/01
JAEA-Technology-2012-039.pdf:3.55MB
Preliminary accident analysis has been carried out for a LOFA (Loss of Flow Accident) and RIAs (Reactivity Insertion Accidents) of the conceptual 10 MW MRR (multi-purpose research reactor) under design study by using the RELAP5/MOD3 code in order to provide the preliminary evaluation of safety margin as well as the intuitions to the design of the MRR. Input and modeling for the RELAP5/MOD3 simulations have also been described. The analysis results indicate that the concept of the MRR is feasible with practical safety margins. The same events have been also analyzed by using the PARET/ANL and the EUREKA-2/RR codes to compare the codes suitability, which have been widely used for the analysis of research reactors. Same geometric and modeling data used for the RELAP5/MOD3 have been used as long as they correspond to each code's input requirements. The three codes show the same or similar overall trends for the events analyzed, but show a small difference in a specific condition.
Kimura, Nobuaki; Imaizumi, Tomomi; Takemoto, Noriyuki; Tanimoto, Masataka; Saito, Takashi; Hori, Naohiko; Tsuchiya, Kunihiko; Romanova, N. K.*; Gizatulin, S.*; Martyushov, A.*; et al.
JAEA-Technology 2012-012, 34 Pages, 2012/06
JAEA-Technology-2012-012.pdf:12.91MB
Si semiconductor production by Neutron Transmutation Doping (NTD) method using the Japan Materials Testing Reactor (JMTR) has been investigated in Neutron Irradiation and Testing Reactor Center, Japan Atomic Energy Agency (JAEA) in order to expand industry use. As a part of investigations, irradiation test of silicon ingot for development of NTD-Si with high quality was planned using WWR-K in Institute of Nuclear Physics (INP), National Nuclear Center of Republic of Kazakhstan (NNC-RK) based on one of specific topics of cooperation (STC), Irradiation Technology for NTD-Si (STC No.II-4), on the implementing arrangement between NNC-RK and the JAEA for "Nuclear Technology on Testing/Research Reactors" in cooperation in research and development in nuclear energy and technology. As for the irradiation test, Si rotating device was fabricated in JAEA, and the fabricated device was transported with irradiation specimens from JAEA to INP-NNC-RK. This report described the design, the fabrication, the performance test of the Si rotating device and transportation procedures.
Imaizumi, Tomomi; Takemoto, Noriyuki; Izumo, Hironobu; Ide, Hiroshi; Matsui, Yoshinori; Sozawa, Shizuo; Hori, Naohiko
JAEA-Review 2012-012, 25 Pages, 2012/03
JAEA-Review-2012-012.pdf:4.21MB
A training course using JMTR and the related facilities was newly organized for domestic students and young engineers from FY 2010 from a viewpoint of nuclear Human Resource Development (HRD) in order to support global expansion of nuclear power industry. In FY2010, preparation for the training course was curried out and the 1st training course was held on February 14 to 25, 2011 with ten domestic students as a trainie. In this training course, mainly carried out was practical training of neutronic calculation for an irradiation test about the hydraulic rabbit irradiation facility which is one of the irradiation facilities in the JMTR. This report summarizes outline of training course using cutting-edge research infrastructure JMTR and the related facilities and result of the 1st training course.
Takemoto, Noriyuki; Imaizumi, Tomomi; Izumo, Hironobu; Hori, Naohiko; Suzuki, Masahide; Ishitsuka, Tatsuo*; Tamura, Kazuo*
JAEA-Conf 2011-003, p.271 - 275, 2012/03
Japan Atomic Energy Agency (JAEA) is now developing a real time simulator for a material testing reactor in order to utilize a nuclear human resource development and promotion of partnership with developing countries which have a plan to introduce nuclear power plant and/or experimental research reactor. The simulator is scheduled to be operated in JFY2012. The simulator is based on Japan Materials Testing Reactor (JMTR), and treats most of JMTR, e.g. reactor, primary cooling system, secondary cooling system, emergency cooling system, instrumentation and control system, safety and protection systems and electricity system. It simulates normal operation condition, transient operation condition such as excess reactivity addition due to testing material insertion and condition of the LOCA. Moreover, it simulates an irradiation experiment using irradiation equipments such as material testing under BWR condition. The simulator is composed of a computer system, a console for reactor control, process control, irradiation equipments, and an instructor and large-size displays. The simulator has the control functions, such as load and store of initial conditions, selection of core conditions, control of execution (run/freeze/fast/slow), save of backtrack snapshots at regular intervals, etc. in order to increase education effects. Furthermore, it has actions, such as malfunctions, remote functions, global component failures, annunciator master control, etc.
Imaizumi, Tomomi; Miyauchi, Masaru; Ito, Masayasu; Watahiki, Shunsuke; Nagata, Hiroshi; Hanakawa, Hiroki; Naka, Michihiro; Kawamata, Kazuo; Yamaura, Takayuki; Ide, Hiroshi; et al.
JAEA-Technology 2011-031, 123 Pages, 2012/01
JAEA-Technology-2011-031.pdf:16.08MB
The number of research reactors in the world is decreasing because of their aging. However, the planning to introduce the nuclear power plants is increasing in Asian countries. In these Asian countries, the key issue is the human resource development for operation and management of nuclear power plants after constructed them, and also the necessity of research reactor, which is used for lifetime extension of LWRs, progress of the science and technology, expansion of industry use, human resources training and so on, is increasing. From above backgrounds, the Neutron Irradiation and Testing Reactor Center began to discuss basic concept of a multipurpose low-power research reactor for education and training, etc. This design study is expected to contribute not only to design tool improvement and human resources development in the Neutron Irradiation and Testing Reactor Center but also to maintain and upgrade the technology on research reactors in nuclear power-related companies. This report treats the activities of the working group from July 2010 to June 2011 on the multipurpose low-power research reactor in the Neutron Irradiation and Testing Reactor Center and nuclear power-related companies.
Imaizumi, Tomomi; Takemoto, Noriyuki; Nagao, Yoshiharu; Kawamura, Hiroshi
JAEA-Review 2009-074, 20 Pages, 2010/03
JAEA-Review-2009-074.pdf:4.11MB
For the neutronic calculation in JMTR, an error of only thermal-neutron-flux tends to extend in specific region, i.e. an irradiation region in beryllium reflectors surrounding the fuel region. From our former investigation, the reason is thought to be the neutron scattering and absorption in the thermal energy region. Therefore, the effect on the thermal neutron scattering law S(,) to hydrogen in light water and to beryllium metal was investigated. As a result, it was confirmed that the error could be caused by the treatment in inelastic scattering within coherent scattering in the beryllium metal, whereas no error factor was found to the hydrogen in light water.
Imaizumi, Tomomi; Kadotani, Hiroyuki*; Okumura, Keisuke; Katakura, Junichi; Nagao, Yoshiharu
no journal, ,
no abstracts in English
Imaizumi, Tomomi; Nagao, Yoshiharu; Kaminaga, Masanori; Ishihara, Masahiro
no journal, ,
no abstracts in English
heating field in JMTRImaizumi, Tomomi; Takemoto, Noriyuki; Nagao, Yoshiharu
no journal, ,
The renewed and upgraded JMTR will start from FY 2011. The JMTR will be use to irradiation test about lifetime extension of light water reactors (LWRs), progress of science and technology, and expansion of industry use. To lifetime extension of LWRs, it is demanded the irradiation test to confirm integrity of reactor structural materials such as stainless steel and concrete, etc. In irradiation tests of concrete sample, it is necessary to keep low irradiation temperature to prevent dehydration of cement hydrates or thermal stress. However, irradiation samples are heated by rays. On the other hand, neutron irradiation test in low heating field is effective as progress of science and technology such as materials basic research. Therefore, the neutron irradiation field of low heating rate was designed in JMTR. In this study, it was considered that the heating rate is below 0.07 W/g in the JMTR core so as not to become higher temperature as planned.
Takemoto, Noriyuki; Imaizumi, Tomomi; Nagao, Yoshiharu
no journal, ,
no abstracts in English
Imaizumi, Tomomi; Hori, Naohiko; Kusunoki, Tsuyoshi; Ishihara, Masahiro
no journal, ,
no abstracts in English
Izumo, Hironobu; Imaizumi, Tomomi; Takemoto, Noriyuki; Hori, Naohiko
no journal, ,
no abstracts in English
Takemoto, Noriyuki; Kimura, Nobuaki; Imaizumi, Tomomi; Hori, Junichi*; Sano, Tadafumi*; Nakajima, Ken*
no journal, ,
no abstracts in English
Imaizumi, Tomomi; Ide, Hiroshi; Yamaura, Takayuki
no journal, ,
In the JMTR, neutronic calculations for core properties such as the shutdown margin, the maximum reactivity, the neutron flux and so on are implemented before each operation cycle. These calculations had been carried out using the SRAC on the JAEA's mainframe. However, the mainframe was abolished in 2012. Additionally, the SRAC used in the JMTR is not available on the computer with the UNIX operating system unlike the SRAC95 and the latest version of SRAC2006. PIJ, CITATION and COREBN are mainly used in neutronic calculations of JMTR. Therefore, these codes were improved to be available on PC-Linux. Furthermore, the new JMTR core management system was also improved by adding a graphical user interface (GUI). By using the new system, the cell and core calculation model can be confirmed visually. In addition, the GUI operation was able to simplify the input operation and the processing of the output result in comparison with the command operations of the past.
Hanakawa, Hiroki; Watahiki, Shunsuke; Ide, Hiroshi; Kitagishi, Shigeru; Imaizumi, Tomomi; Araki, Daisuke; Tobita, Masahiro; Yamaura, Takayuki; Kaminaga, Masanori
no journal, ,
On 18th December 2013, the new regulatory requirements for Japanese research reactor were enforced by the Nuclear Regulation Authority in Japan. This new regulatory requirements are also applied to any research reactor in Japan, even if licensed research reactor. Thus the verification of conformity in the JMTR facilities to the new regulatory requirements was carried out. In this reports, the safety assessment against the beyond design basis accident will be described. At first, events tree analyses were carried out to select beyond design basis accidents. From these analyses, it was confirmed that 8 events can be representative cases. These events were analyzed from the viewpoints of public dose exposer. As the result of analysis, it was confirmed that 3 events out of 8 has a possibility to give the considerable public dose exposer so that the counter measerments were taken account to reduce the dose exposer to acceptable limit.
