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Taniguchi, Yoshinori; Mihara, Takeshi; Kakiuchi, Kazuo; Udagawa, Yutaka
Annals of Nuclear Energy, 195, p.110144_1 - 110144_11, 2024/01
Narukawa, Takafumi; Kondo, Keietsu; Fujimura, Yuki; Kakiuchi, Kazuo; Udagawa, Yutaka; Nemoto, Yoshiyuki
Journal of Nuclear Materials, 582, p.154467_1 - 154467_12, 2023/08
Times Cited Count:0 Percentile:98.57(Materials Science, Multidisciplinary)Furumoto, Kenichiro; Udagawa, Yutaka
Journal of Nuclear Science and Technology, 60(5), p.500 - 511, 2023/05
Times Cited Count:0 Percentile:0.01(Nuclear Science & Technology)Guglielmi, Y.*; Aoki, Kazuhiro; Cook, P.*; Soom, F.*; Cappa, F.*; Tanaka, Yukumo
Tectonophysics, 819, p.229084_1 - 229084_22, 2021/11
Times Cited Count:1 Percentile:13.22(Geochemistry & Geophysics)The reactivation mechanisms of coseismic surface ruptures associated with the 2011 Mw 6.7 Fukushima-ken Hamadori earthquake in Japan are investigated using in-situ controlled hydraulic injections in subsurface boreholes. Two fault segments were selected for reactivation studies, one across a coseismic rupture, the Shionohira site, and one across a non-coseismically ruptured segment, the Minakami-kita site. A series of water injections in sealed sections of boreholes set across the fault progressively bring the fault to rupture by a step-by-step decrease of the effective normal stress clamping the fault. While the fault is rupturing during these hydraulic stimulations, borehole displacements, fluid pressure and injection flowrate are continuously monitored. Then, the tests were analyzed using fully coupled hydromechanical modeling. The model was calibrated on field data, and a parametric study was conducted to examine the modes of fault reactivation. Coseismic surface rupture of the Shionohira fault showed a pure dilatant slip response to hydraulic tests, while the tectonically un-activated Itozawa fault (South) indicated a complex hybrid response to tests related to both a higher frictional and cohesive strengths of the fault. The analysis of the induced Shionohira slip event showed that it is reasonably modeled as a Coulomb rupture with an eventual dependency of friction on slip velocity, in good accordance with laboratory-derived rate-and-state friction data on the Shinohira gouge samples. In contrast, the Itozawa fault reactivation mechanism appears dominated by tensile failure with limited Coulomb shear failure. Thus, the applied protocol proves to be able to isolate significant differences in fault physical properties and rupture mechanisms between two segments of the same fault system, opening perspectives to better assess near-surface rupture effects, and therefore the safety of structures subject to large earthquakes.
Oka, Hiroshi*; Kaito, Takeji; Ikusawa, Yoshihisa; Otsuka, Satoshi
Nuclear Engineering and Design, 370, p.110894_1 - 110894_8, 2020/12
Times Cited Count:0 Percentile:0.01(Nuclear Science & Technology)The objective of this study is to evaluate the reliability of a cumulative damage fraction (CDF) analysis for the prediction of fuel pin breach in fast rector using experimentally obtained fuel pin breach data for the first time. Six breached fuel pins were obtained from steady state irradiation in the EBR-II. Post irradiation examinations revealed that FP gas pressure was the main cause of creep damage in cladding, and that the stress contribution from FCMI was negligible. CDFs evaluated for these pins using in-reactor creep rupture equation, taking into account the irradiation history of cladding temperature and hoop stress due to FP gas pressure, were in the range of 0.7 to 1.4 at the occurrence of breach. This shows clearly that fuel pin breach occurs when the CDF approaches 1.0. The results indicate that CDF analysis would be a reliable method for the prediction of fuel pin breach when appropriate material strength and environmental effects are adopted.
Uchibori, Akihiro; Yanagisawa, Hideki*; Takata, Takashi; Li, J.*; Jang, S.*
Mechanical Engineering Journal (Internet), 7(3), p.19-00548_1 - 19-00548_11, 2020/06
Evaluation of occurrence possibility of tube failure propagation under sodium-water reaction accident is an important issue. In this study, a numerical analysis method to predict occurrence of failure propagation by overheating rupture was constructed to expand application range of an existing computer code. Applicability of the method was constructed through the numerical analysis of the experiment on water vapor discharging in liquid sodium. To improve the evaluation accuracy for the temperature distribution, a Lagrangian particle model for simulating reacting jet was also developed as an alternative method and its basic function was confirmed.
Narukawa, Takafumi; Amaya, Masaki
Journal of Nuclear Science and Technology, 57(1), p.68 - 78, 2020/01
Times Cited Count:2 Percentile:23.14(Nuclear Science & Technology)Taniguchi, Yoshinori; Udagawa, Yutaka; Mihara, Takeshi; Amaya, Masaki; Kakiuchi, Kazuo
Proceedings of International Nuclear Fuel Cycle Conference / Light Water Reactor Fuel Performance Conference (Global/Top Fuel 2019) (USB Flash Drive), p.551 - 558, 2019/09
Onizawa, Takashi; Hashidate, Ryuta
Mechanical Engineering Journal (Internet), 6(1), p.18-00477_1 - 18-00477_15, 2019/02
Aiming at enhancing its economic competitiveness and reducing radioactive waste, JAEA has proposed an attractive plant concept and made great efforts to demonstrate the applicability of some innovative technologies to the plant. One of the most practical means is to extend the design life to 60 years. Accordingly, the material strength standards set by JSME have to be extended from 300,000 to 500,000 hours but this extension requires more precise estimation of creep rupture strength and creep strain of the materials in the long term. This paper describes the development of creep property equations of 316FR stainless steel and Mod.9Cr-1Mo steel considering changes in creep mechanisms at high temperatures in the long term based on evaluations of long-term creep properties of the materials. The creep property equations developed in this study will provide more precise estimation of the creep properties in the long term than the present creep property equations of JSME.
Uchibori, Akihiro; Yanagisawa, Hideki*; Takata, Takashi; Ohshima, Hiroyuki
Proceedings of 11th Korea-Japan Symposium on Nuclear Thermal Hydraulics and Safety (NTHAS-11) (Internet), 6 Pages, 2018/11
Evaluation of occurrence possibility of tube failure propagation under sodium-water reaction accident is an important issue. In this study, a numerical analysis method to predict occurrence of failure propagation by overheating rupture was constructed to expand application range of an existing computer code. Applicability of the method was constructed through the numerical analysis of the experiment on water vapor discharging in liquid sodium.
Uchibori, Akihiro; Takata, Takashi; Yanagisawa, Hideki*; Li, J.*; Jang, S.*
Proceedings of 2018 ANS Winter Meeting and Nuclear Technology Expo; Embedded Topical International Topical Meeting on Advances in Thermal Hydraulics (ATH 2018) (USB Flash Drive), p.1289 - 1294, 2018/11
Evaluation of occurrence possibility of tube failure propagation under sodium-water reaction accident is an important issue. In this study, a numerical analysis method to predict occurrence of failure propagation by overheating rupture was constructed to expand application range of an existing computer code. Applicability of the method was constructed through the numerical analysis of the experiment on water vapor discharging in liquid sodium. To improve the evaluation accuracy for the temperature distribution, a Lagrangian particle model for simulating reacting jet was also developed as an alternative method and its basic function was confirmed.
Yumura, Takanori; Amaya, Masaki
Annals of Nuclear Energy, 120, p.798 - 804, 2018/10
Times Cited Count:4 Percentile:47.96(Nuclear Science & Technology)Takeda, Takeshi
JAEA-Data/Code 2018-004, 64 Pages, 2018/03
Experiment SB-SG-10 was conducted on November 17, 1992 using LSTF. Experiment simulated recovery actions from multiple steam generator (SG) tube rupture accident in PWR. Primary pressure was kept higher than broken SG secondary-side pressure due to coolant injection from high pressure injection (HPI) system into cold and hot legs even after start of full opening of intact SG relief valve (RV). Full opening of power-operated relief valve (PORV) in pressurizer (PZR) resulted in pressure equalization between primary and broken SG systems as well as PZR liquid level recovery. Broken SG RV opened once after start of intact SG RV full opening. Core was filled with saturated or subcooled liquid through experiment. Significant natural circulation prevailed in intact loop after start of intact SG RV full opening. Significant thermal stratification appeared in hot legs especially during time period of HPI coolant injection into hot legs.
Sugawara, Takanori; Tsujimoto, Kazufumi
JAEA-Research 2017-011, 35 Pages, 2017/10
The construction of Transmutation Physics Experimental Facility (TEF-P) is planned in the J-PARC project. TEF-P is a critical assembly and it will treat minor actinide (MA) fuel in the experiment. The temperature when the air cooling for the TEF-P core would stop was estimated but there were no data to evaluate the soundness of the MA fuel pin. To set a tentative limit temperature for the TEF-P core, cladding tube burst experiment was performed. As the result, the cladding tube burst occurred at 660C as the severest case. Through these results and the estimation of creep rupture time, the tentative limit temperature for the TEF-P core was set to 600
C.
Narukawa, Takafumi; Amaya, Masaki
Journal of Nuclear Science and Technology, 53(11), p.1758 - 1765, 2016/11
Times Cited Count:10 Percentile:69.85(Nuclear Science & Technology)Narukawa, Takafumi; Amaya, Masaki
Journal of Nuclear Science and Technology, 53(1), p.112 - 122, 2016/01
Times Cited Count:7 Percentile:56.37(Nuclear Science & Technology)Yamauchi, Michinori*; Sato, Satoshi; Nishitani, Takeo; Kawasaki, Hiromitsu*
Proceedings of 21st IEEE/NPSS Symposium on Fusion Engineering (SOFE 2005) (CD-ROM), 4 Pages, 2005/09
no abstracts in English
JAERI's Internal Investigation Group on the Ruptured Glove; Department of Decommissioning and Waste Management
JAERI-Review 2002-017, 121 Pages, 2002/09
On November 21st, 2001, the glove rupture arose at an incinerator of Waste Treatment Building No.1 in JAERI Tokai Research Establishment. In order to examine the cause and recurrence prevention measure of the rupture, JAERI's Internal Investigation Group on the Ruptured Glove investigated the conditions of the incinerator including ash removing equipment and the glove, types and properties of waste which was incinerated on that day, and background factor of the trouble in cooperation with Department of Decommissioning and Waste Management.As the result, the causes of the rupture were that the solidification of liquid scintillator waste was insufficient, that the protective cover of the glove does not have pressure resistance and the degraded glove was used. For preventing the recurrence of the trouble, the direct confirmation of the solidification condition, the installation of protective cover for the glove, the improvement of the management of the glove, review of manuals and education and training were carried out.
Department of Hot Laboratories
JAERI-Tech 2002-050, 51 Pages, 2002/06
In Hamaoka Nuclear Power Station Unit-1 of Chubu Electric Power Company, a steam leak accident occurred with a pipe rupture. In order to investigate root cause of the pipe rupture, a task force was established within the Nuclear and Industrial Safety Agency (NISA). The JAERI was asked from NISA to cooperate as an independent neutral organization with NISA and perform an examination of the ruptured pipe. The JAERI examination group was formed at the Tokai Research Establishment and conducted some examinations of samples. In Dept. of Hot Laboratories, in order to respond the request of the investigation, the detailed program, various apparatuses, and technical staffs for the examinations are prepared. In this report, technical items in terms of contents of the examination, the used apparatuses, and techniques in three facilities in Dept. of Hot Laboratories (RFEF, RHL, and WASTEF) are summarized.
JAERI Working Group for Examination of the Ruptured Pipe at Hamaoka-1
JAERI-Tech 2002-045, 253 Pages, 2002/03
no abstracts in English