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Udagawa, Yutaka; Sugiyama, Tomoyuki; Amaya, Masaki
Journal of Nuclear Science and Technology, 56(12), p.1063 - 1072, 2019/12
Times Cited Count:8 Percentile:65.94(Nuclear Science & Technology)no abstracts in English
Nagase, Fumihisa; Fuketa, Toyoshi
NUREG/CP-0192, p.197 - 230, 2005/10
The Japanese regulatory criterion for a loss-of-coolant-accident (LOCA) is based on a threshold of fuel rod fracture during quenching, which was experimentally determined under simulated LOCA conditions. In order to evaluate the fracture threshold of high burn-up fuel rods, JAERI performs integral thermal shock tests simulating LOCA conditions. The tests have been performed with pre-hydrided, unirradiated claddings and high burn-up fuel claddings irradiated to 39 and 44 GWd/t at a PWR. It was shown that fracture/no-fracture threshold primarily depends on the oxidation amount and that the threshold decreases with increases in hydrogen concentration and axial restraint during the quench. It was also shown that fracture conditions of the tested high burn-up fuel claddings are consistent with the fracture threshold derived from unirradiated claddings with similar hydrogen concentrations.
Sasajima, Hideo; Sugiyama, Tomoyuki; Nakamura, Takehiko*; Fuketa, Toyoshi
JAERI-Research 2004-022, 113 Pages, 2004/12
Results from power burst tests, GK-1 and GK-2, conducted at the NSRR, are summarized. The tests were performed on a 1414 PWR fuel rod irradiated to a burnup of 42 MWd/kgU in the Genkai unit #1 of Kyushu Electric Power Co., Inc. The instrumented test fuel rod in a double-container-type capsule was subjected to the pulse-irradiation with stagnant water cooling condition at 0.1 MPa and 293 K. Deposited energy and peak fuel enthalpy were 505 J/g and 389 J/g in the Test GK-1, and 490 J/g and 377 J/g in the Test GK-2, respectively. During the pulse-irradiations, DNB occurred and the cladding surface temperature reached 581 K and 569 K in the Tests GK-1 and -2, respectively. The maximum cladding hoop strain was 2.7% in the Test GK-1 and 1.2% in the Test GK-2. However, the test fuel rods did not fail. Estimated fission gas releases during the pulse-irradiations were 11.7% and 7.0% in the Tests GK-1 and -2, respectively.
Nagase, Fumihisa; Fuketa, Toyoshi
Proceedings of 2004 International Meeting on LWR Fuel Performance, p.500 - 506, 2004/09
A systematic research program is being conducted at the Japan Atomic Energy Research Institute (JAERI), which aims at a wide range database for evaluating the influence of further burnup extension on fuel behavior under LOCA conditions. As a part of the program, integral thermal shock tests simulating the whole LOCA sequence have been conducted with Zircaloy-4 fuel claddings, irradiated to 39 and 44GWd/t at a PWR. One cladding, oxidized to about 30% ECR, fractured during the quench. The fracture condition agrees with the fracture criteria for non-irradiated claddings that have similar hydrogen concentrations (about 25% ECR). Two claddings, oxidized to about 16 and 18% ECR, survived the quench, indicating that fracture/non-fracture boundary is not reduced so significantly by irradiation for the examined burnup range. The present paper describes information obtained from the tests including oxidation kinetics and rupture behavior.
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.
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.
Research Committee on Reactor Physics
JAERI-Research 2001-046, 326 Pages, 2001/10
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.
Hee, S. S.*; Suyama, Kenya; Mochizuki, Hiroki*; Okuno, Hiroshi; Nomura, Yasushi
JAERI-Research 2000-066, 131 Pages, 2001/01
no abstracts in English
Ando, Yoshihira*; Nishihara, Kenji; Takano, Hideki
Journal of Nuclear Science and Technology, 37(10), p.924 - 933, 2000/10
no abstracts in English
Kugo, Teruhiko; Okubo, Tsutomu; *
JAERI-Research 99-057, p.29 - 0, 1999/09
no abstracts in English
Kugo, Teruhiko; Shimada, Shoichiro*; Okubo, Tsutomu; Ochiai, Masaaki
JAERI-Research 98-059, 40 Pages, 1998/10
no abstracts in English
M.C.Brady*; ; M.D.DeHart*; A.Nouri*; E.Sartori*
Proc. of Int. Conf. on the Phys. of Nucl. Sci. and Technol., 1, p.624 - 630, 1998/00
no abstracts in English
; Okuno, Hiroshi
JAERI-Research 96-003, 170 Pages, 1996/02
no abstracts in English
Ishijima, Kiyomi; *; Fuketa, Toyoshi; Sasajima, Hideo
NEA/CSNI/R(95)22, 0, p.87 - 105, 1996/00
no abstracts in English
M.C.Brady*; ; M.D.DeHart*; Okuno, Hiroshi; A.Nouri*; E.Sartori*
PHYSOR 96: Int. Conf. on the Physics of Reactors, 4, p.L41 - L52, 1996/00
no abstracts in English
Adachi, Takeo; Nakahara, Yoshinori; Kono, Nobuaki; Gunji, Katsubumi; ; ; ; Kato, Kaneharu; Tachikawa, Enzo; *; et al.
Journal of Nuclear Science and Technology, 31(10), p.1119 - 1129, 1994/10
Times Cited Count:8 Percentile:60.14(Nuclear Science & Technology)no abstracts in English
Onuki, Akira; ; Iguchi, Tadashi; Murao, Yoshio
JAERI-Research 94-012, 59 Pages, 1994/08
no abstracts in English
Yanagisawa, Kazuaki; Katanishi, Shoji;
Journal of Nuclear Science and Technology, 31(7), p.671 - 676, 1994/07
Times Cited Count:0 Percentile:0.01(Nuclear Science & Technology)no abstracts in English
JAERI-M 94-003, 145 Pages, 1994/01
no abstracts in English