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Esser, S. P.*; Rahlff, J.*; Zhao, W.*; Predl, M.*; Plewka, J.*; Sures, K.*; Wimmer, F.*; Lee, J.*; Adam, P. S.*; McGonigle, J.*; et al.
Nature Microbiology (Internet), 8(9), p.1619 - 1633, 2023/09
Times Cited Count:2 Percentile:79.73(Microbiology)Yanagisawa, Hiroshi; Umeda, Miki; Motome, Yuiko; Murao, Hiroyuki
JAEA-Technology 2022-030, 80 Pages, 2023/02
Nuclear criticality benchmark analyses were carried out for TRIGA-type reactor systems in which uranium-zirconium hydride fuel rods are loaded by using the continuous-energy Monte Carlo code MVP with the evaluated nuclear data library JENDL-5. The analyses cover two sorts of benchmark data, the IEU-COMP-THERM-003 and IEU-COMP-THERM-013 in the International Criticality Safety Benchmark Evaluation Project (ICSBEP) Handbook, and effective neutron multiplication factors, reactivity worths for control rods etc. were calculated by JENDL-5 in comparison with those by the previous version of JENDL. As the results, it was confirmed that the effective neutron multiplication factors obtained by JENDL-5 were 0.4 to 0.6% greater than those by JENDL-4.0, and that there were no significant differences in the calculated reactivity worths by between JENDL-5 and JENDL-4.0. Those results are considered to be helpful for the confirmation of calculation accuracy in the analyses on NSRR control rod worths, which are planned in the future.
Herranz, L. E.*; Pellegrini, M.*; Lind, T.*; Sonnenkalb, M.*; Godin-Jacqmin, L.*; Lpez, C.*; Dolganov, K.*; Cousin, F.*; Tamaki, Hitoshi; Kim, T. W.*; et al.
Nuclear Engineering and Design, 369, p.110849_1 - 110849_7, 2020/12
Times Cited Count:20 Percentile:94.29(Nuclear Science & Technology)Phase 2 of the OECD/NEA Project "Benchmark Study of the Accident at the Fukushima Daiichi Nuclear Power Plant (BSAF)" was established in mid-2015. The objectives have been similar to Phase 1 of the project but with an extended analysis period of 3 weeks, a major focus on FP behaviour and releases to the environment and the comparison to various data and results of backwards calculations of the source term. Nine organizations of six countries submitted results of their calculated severe accident scenarios for Unit 1 at the 1F site using different severe accident codes. This paper describes the findings of the comparison of the participants results for Unit1 against each other and against plant data, the evaluation of the accident progression and the final status inside the reactors. Special focus is on RPV status, melt release and FP behaviour and release. Unit specific aspects will be highlighted and points of consensus as well as remaining uncertainties and data needs will be summarised.
Sonnenkalb, M.*; Pellegrini, M.*; Herranz, L. E.*; Lind, T.*; Morreale, A. C.*; Kanda, Kenichi*; Tamaki, Hitoshi; Kim, S. I.*; Cousin, F.*; Fernandez Moguel, L.*; et al.
Nuclear Engineering and Design, 369, p.110840_1 - 110840_10, 2020/12
Times Cited Count:22 Percentile:95.22(Nuclear Science & Technology)This is the second paper in a series of 3 in which results of severe accident analyses for Unit 2 of Fukushima Daiichi are presented, gained in Phase 2 of the OECD/NEA project "Benchmark Study of the Accident at the Fukushima Daiichi Nuclear Power Plant (BSAF)". Nine organizations of six countries submitted results of their calculated severe accident scenarios for Unit 2 of Fukushima Daiichi using different severe accident codes. The present paper describes the findings of the comparison of the participants' results for Unit 2 against each other and against plant data, the evaluation of the accident progression and the final status inside the reactors. Special focus is on reactor pressure vessel status, melt release and fission product behavior and release. Unit 2 specific aspects will be highlighted and points of consensus as well as remaining uncertainties and data needs will be summarized.
Thwe Thwe, A.; Terada, Atsuhiko; Hino, Ryutaro
JAEA-Technology 2018-012, 45 Pages, 2019/01
Under long-term storage of nuclear wastes including low- and high-level wastes, hydrogen can be spontaneously generated from corrosion of metal wastes and container wall itself, and from radiolysis of water in the waste. For the sake of hydrogen safety and the risk reduction of environmental contamination, we have started to investigate the behavior and characteristics of hydrogen combustion and explosion in waste vessel. In this report, we performed numerical simulation to investigate the characteristics of methane combustion by applying OpenFOAM. For combustion scenario, FireFoam solver with LES frame was used. As the results, the average temperature increased when the container height and inlet size increased. The simulation of gas diffusion by FireFoam results showed that helium diffused faster than hydrogen and methane. By XiFoame solver, the simulation was performed to obtain flame propagation radius for hydrogen-air premixed flame.
Yanagisawa, Kazuaki; Takahashi, Shoji*
Scientometrics, 78(3), p.505 - 524, 2008/10
Times Cited Count:1 Percentile:24.99(Computer Science, Interdisciplinary Applications)A socio-economic evaluation of Material Science (MS) of JAERI was made. The goal was to reveal the emphasized basic research fields (EBRF) of MS and to observe its socio-economic networking. High ranked keywords for the former and the number of co-authored papers for the latter were used along with many MS related papers. The obtained results are: (1) The EBRF of MS of JAERI were typically represented by the keywords of ion irradiation, actinides, etc., i.e., those having a strong relation to the nuclear field. Regarding actinides, the socio-economic networking between JAERI and PS occurred at the growth rate of 3-4% per 25 years, but 8% during the past 5 years. This implies that the research cooperation between the two was markedly enhanced. (2) The EBRF of MS between JAERI and 5 selected research bodies (SRB) represented by Tokyo University was directly compared and revealed that only 7 keywords as typically represented by neutron and accelerators. After overlapping, JAERI and SRB seem to be raising the national standard level.
Ishikura, Shuichi*; Kogawa, Hiroyuki; Futakawa, Masatoshi; Kikuchi, Kenji; Haga, Katsuhiro; Kaminaga, Masanori; Hino, Ryutaro
JAERI-Tech 2003-093, 55 Pages, 2004/01
To estimate the structural integrity of the heavy liquid-metal (Hg) target used in a MW-class neutron scattering facility, static and dynamic stress behaviors due to the incident of a 1MW-pulsed proton beam were analyzed. In the analyses, two-type target containers with semi-cylindrical type and flat type window were used as analytical models of the structural analysis codes LS-DYNA. As a result, it is confirmed that the stress generated by dynamic thermal shock becomes the largest at the center of window, and the flat type window is more advantageous from the structural viewpoint than the semi-cylindrical type window. It was confirmed to erosion damage the target container by mercury's becoming negative pressure in the window and generating the cavitation by the experiment. Therefore, it has been understood that the point top of the window was in the compression stress field by the steady state thermal stress because of the evaluation from destroying the dynamic viewpoint for the crack in the generated pit and the pit point, and the crack did not progress.
Nakajima, Ken; Yamamoto, Toshihiro; Miyoshi, Yoshinori
Journal of Nuclear Science and Technology, 39(11), p.1162 - 1168, 2002/11
Times Cited Count:8 Percentile:47.9(Nuclear Science & Technology)A modified quasi-steady-state method has been developed to evaluate the mean power during a nuclear excursion in fissile solution. The original method used the critical equation based on the one-group theory to calculate the reactivity. However, the one-group approximation reduces the calculation accuracy and the geometrical buckling used in the critical equation is not applicable to complex geometries. Then, we have modified the method to use the feedback coefficients of reactivity. Although the modified method requires an external calculation to obtain the feedback coefficients, it is applicable to complex geometries and gives more accurate results than the one-group approximation. Moreover, a new method to calculate the boiling power has been developed. using the experimental data of a supercritical experiment facility, SILENE. Experimental analyses were conducted to validate the new method for supercritical xperiments using CRAC and TRACY. The results showed good agreements with the experiments.
Takeda, Seiji; Kimura, Hideo
JAERI-Research 2002-014, 20 Pages, 2002/07
no abstracts in English
*; ; Nakamura, Hideo
JAERI-Research 98-022, 46 Pages, 1998/03
no abstracts in English
Nakamura, Hideo; Ito, Kazuhiro*; Kukita, Yutaka*; *; ; Maekawa, Hiroshi; Katsuta, Hiroji
Journal of Nuclear Materials, 258-263, p.440 - 445, 1998/00
Times Cited Count:7 Percentile:53.8(Materials Science, Multidisciplinary)no abstracts in English
Nakane, Yoshihiro; Nakashima, Hiroshi; Nakao, Noriaki*; Ueki, Kotaro*
Proc. of 3rd Workshop on Simulating Accelerator Radiation Environments (SARE3), p.334 - 342, 1997/00
no abstracts in English
Araya, Fumimasa; *; Ochiai, Masaaki
Proc. of Post-SMiRT14 Int. Seminar 18, p.E1.26 - E1.32, 1997/00
no abstracts in English
Sato, Satoshi; Furuya, Kazuyuki; Kuroda, Toshimasa*; Kurasawa, Toshimasa; *; Hatano, Toshihisa; Takatsu, Hideyuki; Osaki, Toshio*
16th IEEE/NPSS Symp. on Fusion Engineering (SOFE '95), 1, p.202 - 205, 1996/00
no abstracts in English
*; Kunugi, Tomoaki; *
Nihon Kikai Gakkai Rombunshu, B, 61(586), p.2228 - 2234, 1995/06
no abstracts in English
Takase, Kazuyuki; Akino, Norio
Kikai Gakkai Ibaraki Koenkai Koen Rombunshu, 0, p.127 - 128, 1995/00
no abstracts in English
*; *; *; Kunugi, Tomoaki
Therm. Sci. Eng., 2(2), p.16 - 25, 1994/00
no abstracts in English
Kunugi, Tomoaki; *; *
Heat Transfer in Turbulent Flows, 1993; HTD-Vol. 246, p.25 - 31, 1993/00
no abstracts in English
Maeda, Mitsuru; Fujine, Sachio; *; *
Transactions of the American Nuclear Society, 66, p.78 - 80, 1992/11
no abstracts in English
Okubo, Tsutomu; Iwamura, Takamichi; *; *; Murao, Yoshio
6th Proc. of Nuclear Thermal Hydraulics, p.79 - 86, 1990/11
no abstracts in English