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Yamashita, Shinichiro; Ioka, Ikuo; Nemoto, Yoshiyuki; Kawanishi, Tomohiro; Kurata, Masaki; Kaji, Yoshiyuki; Fukahori, Tokio; Nozawa, Takashi*; Sato, Daiki*; Murakami, Nozomu*; et al.
Proceedings of International Nuclear Fuel Cycle Conference / Light Water Reactor Fuel Performance Conference (Global/Top Fuel 2019) (USB Flash Drive), p.206 - 216, 2019/09
After the nuclear accident at Fukushima Daiichi Power Plant, research and development (R&D) program for establishing technical basis of accident-tolerant fuel (ATF) started from 2015 in Japan. Since then, both experimental and analytical studies necessary for designing a new light water reactor (LWR) core with ATF candidate materials are being conducted within the Japanese ATF R&D Consortium for implementing ATF to the existing LWRs, accompanying with various technological developments required. Until now, we have accumulated experimental data of the candidate materials by out-of-pile tests, developed fuel evaluation codes to apply to the ATF candidate materials, and evaluated fuel behavior simulating operational and accidental conditions by the developed codes. In this paper, the R&D progresses of the ATF candidate materials considered in Japan are reviewed based on the information available such as proceedings of international conference and academic papers, providing an overview of ATF program in Japan.
Yamashita, Shinichiro; Nagase, Fumihisa; Kurata, Masaki; Nozawa, Takashi; Watanabe, Seiichi*; Kirimura, Kazuki*; Kakiuchi, Kazuo*; Kondo, Takao*; Sakamoto, Kan*; Kusagaya, Kazuyuki*; et al.
Proceedings of 2017 Water Reactor Fuel Performance Meeting (WRFPM 2017) (USB Flash Drive), 10 Pages, 2017/09
In Japan, the research and development (R&D) project on accident tolerant fuel and other components (ATFs) of light water reactors (LWRs) has been initiated in 2015 for establishing technical basis of ATFs. The Japan Atomic Energy Agency (JAEA) has coordinated and carried out this ATF R&D project in cooperation with power plant providers, fuel venders and universities for making the best use of the experiences, knowledges in commercial uses of zirconium-base alloys (Zircaloy) in LWRs. ATF candidate materials under consideration in the project are FeCrAl steel strengthened by dispersion of fine oxide particles(FeCrAl-ODS) and silicon carbide (SiC) composite, and are expecting to endure severe accident conditions in the reactor core for a longer period of time than the Zircaloy while maintaining or improving fuel performance during normal operations. In this paper, the progresses of the R&D project are reported.
Ishibashi, Ryo*; Tanabe, Shigetada*; Kondo, Takao*; Yamashita, Shinichiro; Nagase, Fumihisa
Proceedings of 2017 Water Reactor Fuel Performance Meeting (WRFPM 2017) (USB Flash Drive), 10 Pages, 2017/09
For improving the corrosion resistance of silicon carbide (SiC) in boiling-water-reactor environments, corrosion-resistant coatings on SiC were evaluated. Due to its hydrogen-generation rate and reaction heat being lower than those of conventional Zircaloy, SiC is expected to be an appropriate material for accident-tolerant fuels. However, there are still many critical issues with the practical application of SiC fuel cladding and fuel channel boxes, one of which is hydrothermal corrosion. Silicon carbide is chemically stable, but silicon oxide formed by oxidation of SiC dissolves in high temperature water. Although the rate of SiC dissolution is very small, the dissolution must be suppressed to comply with regulations for dissolved silica concentration in reactor coolant. In this study, the corrosion behavior of candidate coatings for SiC substrates were evaluated before and after exposure to unirradiated high-purity-water environments.
Sakamoto, Kan*; Hirai, Mutsumi*; Ukai, Shigeharu*; Kimura, Akihiko*; Yamaji, Akifumi*; Kusagaya, Kazuyuki*; Kondo, Takao*; Yamashita, Shinichiro
Proceedings of 2017 Water Reactor Fuel Performance Meeting (WRFPM 2017) (USB Flash Drive), 7 Pages, 2017/09
This paper will show the overview of current status of development of accident tolerant FeCrAl-ODS fuel claddings for BWRs (boiling water reactors) in the program sponsored and organized by the Ministry of Economy, Trade and Industry (METI) of Japan. This program is being carried out to create the technical basis for the practical use of the accident tolerant fuels and the other components in LWRs through multifaceted activities. In the development of FeCrAl-ODS fuel claddings both the experimental and the analytical studies have been performed. The acquisition and accumulation of key material properties of FeCrAl-ODS fuel claddings were conducted by using bar, sheet and tube shaped FeCrAl-ODS materials fabricated in this program to support the evaluations in the analytical studies. A neutron irradiation test was also started in the ORNL High Flux Isotope Reactor (HFIR) to examine the effect of neutron irradiation on the mechanical properties.
Kugo, Teruhiko; Ishikawa, Makoto; Nagaya, Yasunobu; Yokoyama, Kenji; Fukaya, Yuji; Maruyama, Hiromi*; Ishii, Yoshihiko*; Fujimura, Koji*; Kondo, Takao*; Minato, Hirokazu*; et al.
JAEA-Research 2013-046, 53 Pages, 2014/03
The present report summarizes the results of a 2-year cooperative study between JAEA and Hitachi-GE in order to contribute to the settlement of the Fukushima-Daiichi Nuclear Power Plants which suffered from the severe accident on March 2011. In the present study, the possible scenarios to reach the recriticality events in Fukushima-Daiichi were investigated first. Then, the analytical methodology to evaluate the time-dependent recriticality events has been developed by modelling the reactivity insertion rate and the possible feedback according to the recriticality scenarios identified in the first step. The methodology developed here has been equipped as a transient simulation tool, PORCAS, which is operated on a multi-purpose platform for reactor analysis, MARBLE. Finally, the radiation exposure rates by the postulated recriticality events in Fukushima-Daiichi were approximately evaluated to estimate the impact to the public environment.
Nakai, Hirohito*; Ebihara, Takao*; Tsutsui, Satoshi*; Mizumaki, Masaichiro*; Kawamura, Naomi*; Michimura, Shinji*; Inami, Toshiya; Nakamura, Toshiyuki*; Kondo, Akihiro*; Kindo, Koichi*; et al.
Journal of the Physical Society of Japan, 82(12), p.124712_1 - 124712_5, 2013/12
Times Cited Count:7 Percentile:48.56(Physics, Multidisciplinary)The temperature and magnetic field dependences of Yb valence were observed in the heavy fermion compoundYbRhSi
by X-ray absorption spectroscopy. The measurements revealed that the Yb valence decreases with decreasing temperature in the range from 200 to 2 K and increases with increasing magnetic field in the range from 0 to 33 T without showing an abrupt change in the Yb valence. The Yb valence is in the range from 2.92 to 2.96 depending on temperature and magnetic field. With respect to the valence being 2.92 at 0 T and 2.93 at 33 T in 2 K, YbRh
Si
is a valence fluctuation compound and does not reach the integer trivalent state at high magnetic field. These results endorse the conventional knowledge that the valence of Yb is very close to the integer value of 3+, decreases with decreasing temperature, and becomes closer to 3+ with increasing magnetic field.
Hasegawa, Makoto; Kondo, Hitoshi; Kamei, Gento; Hirano, Fumio; Mihara, Morihiro; Takahashi, Kuniaki; Funabashi, Hideyuki; Kawatsuma, Shinji; Ueda, Hiroyoshi*; Oi, Takao*; et al.
JAEA-Research 2011-003, 47 Pages, 2011/02
In 2009, NUMO and JAEA set up a technical commission to investigate the reasonable TRU waste disposal following a cooperation agreement between these two organizations. In this report, the calculation result of radionuclide transport for a TRU waste geological disposal system was described, by using the TIGER code and the GoldSim code at identical terms. Comparing the calculation result, a big difference was not seen. Therefore, the reliability of both codes was able to be confirmed. Moreover, the influence on the disposal site design (Disposal capacity: 19,000 m) was examined when 10% of the amount of TRU waste increased. As a result, it was confirmed that the influence of the site design was very little based on the concept of the Second Progress Report on Research and Development for TRU Waste Disposal in Japan.
Nakanii, Nobuhiko*; Kondo, Kiminori; Yabuuchi, Toshinori*; Tsuji, Kazuki*; Tanaka, Kazuo*; Suzuki, Shinsuke*; Asaka, Takao*; Yanagida, Kenichi*; Hanaki, Hirofumi*; Kobayashi, Takashi*; et al.
Review of Scientific Instruments, 79(6), p.166102_1 - 066102_3, 2008/06
An imaging plate has been used as a useful detector of energetic electrons in laser electron acceleration and laser fusion studies. The absolute sensitivity of an imaging plate was calibrated at 1 GeV electron energy using the injector Linac of SPring-8. The sensitivity curve obtained up to 100 MeV in a previous study was extended successfully to GeV range.
Kubota, Naoyoshi; Ochiai, Kentaro; Kutsukake, Chuzo; Hayashi, Takao; Shu, Wataru; Kondo, Keitaro; Verzilov, Y.*; Sato, Satoshi; Yamauchi, Michinori; Nishi, Masataka; et al.
Proceedings of 21st IAEA Fusion Energy Conference (FEC 2006) (CD-ROM), 7 Pages, 2007/03
Fuel and impurity particles show complicated behavior on the surface of plasma facing components (PFC) in fusion devices. The study is important for the design of the fuel recycling, safety management of the tritium inventory, etc. Quantitative measurements of hydrogen and lithium isotopes together with other impurities on the PFC surface exposed to D-T plasmas in TFTR were performed using the deuteron-induced nuclear reaction analysis, imaging plate method, full combustion method and activation analysis. The tritium depth profile was different from deuterium one. The surface tritium largely contributed to the whole tritium in the sample. On the other hand, the retained amount of lithium-6 was lager than that of lithium-7. This relates to the injection of enriched lithium-6 pellets in some campaigns. No other impurities were detected. So the large amount of tritium remained near the surface and did not diffuse more deeply, which gives a bright prospect for tritium safety.
Ueshima, Yutaka; Kondo, Takao*; Isogai, Kentaro*
Joho Shori Gakkai MPS Shimpojiumu Rombunshu, 2003(14), p.151 - 158, 2003/10
no abstracts in English
Sakamoto, Kan*; Hirai, Mutsumi*; Ukai, Shigeharu*; Kimura, Akihiko*; Yamaji, Akifumi*; Kusagaya, Kazuyuki*; Kondo, Takao*; Ioka, Ikuo; Yamashita, Shinichiro; Kaji, Yoshiyuki
no journal, ,
no abstracts in English
Kakiuchi, Kazuo*; Sato, Hisaki*; Ishibashi, Ryo*; Kondo, Takao*; Ioka, Ikuo; Yamashita, Shinichiro; Kaji, Yoshiyuki
no journal, ,
no abstracts in English
Yamashita, Shinichiro; Ioka, Ikuo; Nemoto, Yoshiyuki; Shirasu, Noriko; Kurata, Masaki; Kaji, Yoshiyuki; Fukahori, Tokio; Watanabe, Seiichi*; Kirimura, Kazuki*; Kakiuchi, Kazuo*; et al.
no journal, ,
Since the accident at Fukushima Daiichi Nuclear Power Station, enhancing the accident tolerance of Light Water Reactors (LWRs) became a topic of serious discussion, and the research and development (R&D) for improving the safety LWRs has been activated in many countries. In Japan, the R&D project on accident tolerant fuel and other components (ATFs) of LWRs, which is sponsored and organized by the Ministry of Economy, Trade and Industry (METI), has been initiated in 2015 for establishing technical basis of ATFs. The Japan Atomic Energy Agency (JAEA) has coordinated and carried out this ATF R&D project in cooperation with power plant providers, fuel venders and universities for making the best use of the experiences, knowledges in commercial uses of zirconium-base alloys in LWRs.
Ishibashi, Ryo*; Kondo, Takao*; Yamashita, Shinichiro
no journal, ,
no abstracts in English
Yamashita, Shinichiro; Ioka, Ikuo; Nemoto, Yoshiyuki; Shirasu, Noriko; Kurata, Masaki; Kaji, Yoshiyuki; Fukahori, Tokio; Watanabe, Seiichi*; Murakami, Nozomu*; Sato, Hisaki*; et al.
no journal, ,
Since the accident at Fukushima Daiichi Nuclear Power Station, enhancing the accident tolerance of Light Water Reactors (LWRs) became a topic of serious discussion, and the research and development for improving the safety LWRs has been activated in many countries. This project is one of the projects that entrusted from the Ministry of Economy, Trade and Industry Agency for Natural Resources and Energy. Using a domestic human source, an analysis tool, know-how and experience, the basic technique to apply an accident tolerant fuel material to an existing LWRs is developed in the project. It is started from October, 2015 and is carrying out this project continuously.
Sakamoto, Kan*; Ukai, Shigeharu*; Kimura, Akihiko*; Yamaji, Akifumi*; Kusagaya, Kazuyuki*; Kondo, Takao*; Yamashita, Shinichiro; Fukahori, Tokio
no journal, ,
Using the acquired material data by 2016, the feasibility of the reactor core, accident progress relaxation effect at an accident and a severe accident were confirmed by various analysis when Zircaloy replaced to FeCrAl-ODS steel. The results including the post irradiation examination in fiscal year 2017 will be introduced by this presentation.
Sato, Hisaki*; Kakiuchi, Kazuo*; Ishibashi, Ryo*; Ikegawa, Tomohiko*; Kondo, Takao*; Yamashita, Shinichiro; Fukahori, Tokio
no journal, ,
SiC composite materials applied to a cladding tube and a channel box for BWR have been developed for introduction of the accident tolerant fuel to an existing LWRs. The outline of the outcome in fiscal year 2017 will be introduced by this presentation.
Yamashita, Shinichiro; Ioka, Ikuo; Nemoto, Yoshiyuki; Kawanishi, Tomohiro; Kaji, Yoshiyuki; Fukahori, Tokio; Nozawa, Takashi*; Watanabe, Seiichi*; Murakami, Nozomu*; Sato, Hisaki*; et al.
no journal, ,
Yamashita, Shinichiro; Ioka, Ikuo; Nemoto, Yoshiyuki; Kawanishi, Tomohiro; Kaji, Yoshiyuki; Fukahori, Tokio; Nozawa, Takashi*; Watanabe, Seiichi*; Murakami, Nozomu*; Sato, Hisaki*; et al.
no journal, ,
Yamashita, Shinichiro; Ioka, Ikuo; Nemoto, Yoshiyuki; Kawanishi, Tomohiro; Kurata, Masaki; Kaji, Yoshiyuki; Fukahori, Tokio; Nozawa, Takashi*; Sato, Daiki*; Murakami, Nozomu*; et al.
no journal, ,
Research and development (R&D) program for establishing technical basis of ATFs for light water reactor (LWR) started in 2015. Since then the R&D is being conducted in cooperation with power plant providers, fuel venders, research institutes and universities for making the most use of the experiences in R&D, practical design, and evaluations of fuels and cores of commercial LWRs. Among currently explored ATF candidate materials in the program, silicon carbide composite reinforced by SiC fiber (SiC/SiC) and FeCrAl steel strengthened by dispersion of fine oxide particles (FeCrAl-ODS) offer several attractive features including the remarkable high temperature capabilities and the slow kinetics of steam oxidation reactions. This presentation will give an overview of the progress in ATF development and review the current status of data availability and integrity for the properties and behaviors of ATF candidate materials, followed by discussion on the primary differences from zirconium alloy in the behaviors in the severe accident scenarios. Finally, subjects to be solved for practical use of ATF will be summarized.
Yamashita, Shinichiro; Ioka, Ikuo; Nemoto, Yoshiyuki; Kurata, Masaki; Kawanishi, Tomohiro; Kaji, Yoshiyuki; Fukahori, Tokio; Watanabe, Seiichi*; Murakami, Nozomu*; Sato, Hisaki*; et al.
no journal, ,
In Japan, research and development (R&D) program for establishing technical basis of ATF started in 2015 and is being conducted in cooperation with power plant providers, fuel venders and universities for making the most use of the experiences in R&D, practical design, and evaluations of fuels and cores of commercial LWRs. The present paper reviews the progress of the development and summarizes subjects to be solved for ATF cladding, based on the attribute guide which was originally drawn up in the Japanese ATF R&D program as it should be an indicator of proper ATF development guidance.