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Matsuda, Norihiro; Kunieda, Satoshi; Okamoto, Tsutomu*; Tada, Kenichi; Konno, Chikara
Progress in Nuclear Science and Technology (Internet), 6, p.225 - 229, 2019/01
Kitada, Takanori*; Okumura, Keisuke; Unesaki, Hironobu*; Saji, Etsuro*
Proceedings of International Conference on Physics of Fuel Cycles and Advanced Nuclear Systems; Global Developments (PHYSOR 2004) (CD-ROM), 8 Pages, 2004/04
Burnup calculation benchmark has been carried out for the LWR next generation fuels aiming at high burnup up to 70 GWd/t with UO
and MOX. Based on the submitted results by many benchmark participants, the present status of calculation accuracy has been confirmed for reactor physics parameters of the LWR next generation fuels, and the factors causing the calculation differences were analyzed in detail. Moreover, the future experiments and research subjects necessary to reduce the calculation differences were discussed and proposed.
Research Committee on Reactor Physics
JAERI-Research 2004-004, 409 Pages, 2004/03
JAERI-Research-2004-004.pdf:28.53MB
This report summarizes the second phase (FY2001-2002) activity of "the Working Party (WP) on Reactor Physics for LWR Next Generation Fuels". The next generation fuels mean the ones aiming at further extended burn-up such as 70GWd/t over the current design. In the WP, the benchmark activity has been conducted to investigate and improve the calculation accuracy of the nuclear characteristics of the next generation fuels. In the second phase activity, all benchmark results were compiled and compared. Based on the comparison, the present status of calculation accuracy for the next generation fuels has been confirmed, and the factors causing the calculation differences were analyzed in detail. Moreover, analyses of the post irradiation and critical experiments with the codes used in the benchmark were reviewed, and future experiments and research subjects necessary to reduce the calculation differences were discussed and proposed.
Okuno, Hiroshi
Journal of Nuclear Science and Technology, 40(7), p.544 - 551, 2003/07
Times Cited Count：0 Percentile：0.01(Nuclear Science & Technology)A method for classifying benchmark results of criticality calculations according to similarity was proposed in this paper. After formulation of the method utilizing correlation coefficients, it was applied to burnup credit criticality benchmarks Phase III-A and II-A, which were conducted by the Expert Group on Burnup Credit Criticality Safety under auspices of the OECD/NEA. Phase III-A benchmark was a series of criticality calculations for irradiated BWR fuel assemblies, whereas Phase II-A benchmark was a suite of criticality calculations for irradiated PWR fuel pins. These benchmark problems and their results were summarized. The correlation coefficients were calculated and sets of benchmark results were classified according to the criterion that the correlation coefficients were no less than 0.15 for Phase III-A and 0.10 for Phase II-A benchmarks. When a couple of results were in a same group, one result was found predictable from the other. An example was shown for each of the Benchmarks. The evaluated nuclear data seemed the main factor of errors.
Unesaki, Hironobu*; Okumura, Keisuke; Kitada, Takanori*; Saji, Etsuro*
Transactions of the American Nuclear Society, 88, p.436 - 438, 2003/06
In order to investigate the calculation accuracy of the nuclear characteristics of LWR next generation fuels, the Research Committee on Reactor Physics organized by JAERI has proposed "Reactor Physics Benchmark for LWR Next Generation Fuels". The next generation fuels aim at very high burn-up of about 70GWd/t in PWR or BWR with UO or MOX fuels whose fissile enrichments may exceed the Japanese regulatory limitations for the current LWR fuels such as 5wt.% U-235. Until now, twelve organizations have pariticipated in the benchmark activity. From the comparison with the cell burn-up calculation results using different codes and library data, status of the calculation accuracy and future subjects are clarified.
Okuno, Hiroshi; Sakai, Tomohiro*
Nuclear Technology, 140(3), p.255 - 265, 2002/12
Times Cited Count：0 Percentile：0.01(Nuclear Science & Technology)In order to facilitate discussions based on quantitative analysis about the end effect, which is often talked about in connection to burnup credit in criticality safety evaluation of spent fuel, we introduced in this paper a burnup importance function. This function shows the burnup effect on the reactivity as a function of the fuel position; an explicit expression of this function was derived according to the perturbation theory. The burnup importance function was applied to the Phase IIA benchmark model that was adopted by the OECD/NEA Expert Group on Burnup Credit Criticality Safety. The function clearly displayed that burnup importance of the end regions increases (1) as burnup, (2) as cooling time, (3) in consideration of burnup profile, and (4) in consideration of fission products.
Okumura, Keisuke; Unesaki, Hironobu*; Kitada, Takanori*; Saji, Etsuro*
Proceedings of International Conference on the New Frontiers of Nuclear Technology; Reactor Physics, Safety and High-Performance Computing (PHYSOR 2002) (CD-ROM), 10 Pages, 2002/10
In order to investigate the calculation accuracy of the nuclear characteristics of LWR next generation fuels, the Research Committee on Reactor Physics organized by Japan Atomic Energy Research Institute has proposed "Reactor Physics Benchmark for LWR Next Generation Fuels". The next generation fuels aim at very high burn-up of about 70GWd/t in PWR or BWR with UO2 or MOX fuels whose fissile enrichments may exceed the Japanese regulatory limitations for the current LWR fuels such as 5wt.% U-235. Twelve organizations have carried out the analyses of the benchmark problems with different codes and data, and their submitted results have been compared. As a result, status of accuracy with the current data and method and some problems to be solved in the future were clarified.
Okuno, Hiroshi; Tonoike, Kotaro; Sakai, Tomohiro*
Proceedings of International Conference on the New Frontiers of Nuclear Technology; Reactor Physics, Safety and High-Performance Computing (PHYSOR 2002) (CD-ROM), 8 Pages, 2002/10
As the burnup proceeds, reactivity of fuel assemblies for light water reactors decreases by depletion of fissile nuclides, especially in the axially central region. In order to describe the importance of the end regions to the reactivity change, a burnup importance function was introduced as a weighting function to a local burnup variation contributed to a reactivity decrease. The function was applied to the OECD/NEA/BUC Phase II-A model and a simplified Phase II-C model. The application to Phase II-A model clearly showed that burnup importance of the end regions increases as burnup and/or cooling time increases. Comparison of the burnup importance function for different initial enrichments was examined. The application result to the simplified Phase II-C model showed that the burnup importance function was helpful to find the most reactive fuel burnup distribution under the conditions that the average fuel burnup was kept constant and the variations in the fuel burnup were within the maximum and minimum measured values.
Research Committee on Reactor Physics
JAERI-Research 2001-046, 326 Pages, 2001/10
JAERI-Research-2001-046.pdf:14.45MB
The Working Party on Reactor Physics for LWR Next Generation Fuels in the Research Committee on Reactor Physics, which is organized by the Japan Atomic Energy Research Institute, has recently proposed a series of benchmark problems to investigate the calculation accuracy of the nuclear characteristics of LWR next generation fuels. The next generation fuels mean the ones aiming for further extended burnup such as 70GWd/t over the current design. The resultant specifications of the benchmark problem therefore neglect some of the current limitations such as 5wt%235U to achieve the above-mentioned target. The Working Party proposed six benchmark problems, which consist of pin-cell, PWR assembly and BWR assembly geometries loaded with uranium and MOX fuels, respectively. The present report describes the detailed specifications of the benchmark problems. The results of preliminary analyses performed by the eleven member organizations and their comparisons are also presented.
Okumura, Keisuke; Mori, Takamasa; Nakakawa, Masayuki; Kaneko, Kunio*
Journal of Nuclear Science and Technology, 37(2), p.128 - 138, 2000/02
no abstracts in English
Konno, Chikara
Mathematics and Computation, Reactor Physics and Environmental Analysis in Nuclear Applications, p.1755 - 1764, 1999/09
no abstracts in English
Maekawa, Fujio; Konno, Chikara; Oyama, Yukio; Uno, Yoshitomo; Maekawa, Hiroshi; Ikeda, Yujiro
Fusion Engineering and Design, 42, p.275 - 280, 1998/00
Times Cited Count：0 Percentile：0.01(Nuclear Science & Technology)no abstracts in English
; Okuno, Hiroshi
JAERI-Research 96-003, 170 Pages, 1996/02
JAERI-Research-96-003.pdf:5.24MB
no abstracts in English
; Yamane, Tsuyoshi; Sasa, Toshinobu
JAERI-Data/Code 94-013, 17 Pages, 1994/10
JAERI-Data-Code-94-013.pdf:0.77MB
no abstracts in English
JAERI-M 94-003, 145 Pages, 1994/01
no abstracts in English
Fujimura, Toichiro
Computer Physics Communications, 82, p.111 - 119, 1994/00
Times Cited Count：1 Percentile：21.58(Computer Science, Interdisciplinary Applications)no abstracts in English
Mori, Takamasa; Nakakawa, Masayuki
Journal of Nuclear Science and Technology, 29(11), p.1061 - 1073, 1992/11
no abstracts in English
Kugo, Teruhiko; Nakakawa, Masayuki;
JAERI-M 92-117, 70 Pages, 1992/08
no abstracts in English
JAERI-M 87-063, 133 Pages, 1987/04
no abstracts in English
Nomura, Yasushi; Katakura, Junichi; Naito, Yoshitaka; Komuro, Yuichi; Okuno, Hiroshi
JAERI 1303, 152 Pages, 1986/11
no abstracts in English
