Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Daimon, Shunsuke*; Uchida, Kenichi*; Ujiie, Naomi*; Hattori, Yasuyuki*; Tsuboi, Rei*; Saito, Eiji
Applied Physics Express, 13(10), p.103001_1 - 103001_4, 2020/10
Times Cited Count：7 Percentile：44.34(Physics, Applied)Morihira, Masayuki; Mizusako, Fumiki*; Tsuboi, Yasushi*
Proceedings of International Conference on Toward and Over the Fukushima Daiichi Accident (GLOBAL 2011) (CD-ROM), 6 Pages, 2011/12
Cladding inner corrosion is one of the life controlling factors of FBR MOX fuels and it depends on the oxygen potential in a fuel element. Oxygen potential increases with extension of burn-up due to the cumulated excess oxygen during fission. The oxygen getter method is idea way to locate metal fragments in a fuel element as an excess oxygen absorber. Since almost nothing has been reported concerning the application of an oxygen getter in pellet type fuels, conceptual development of the oxygen getter for pellet type MOX fuel and a feasibility study were done. For getter material, titanium was mainly evaluated in this study except for compatibility tests carried out for titanium and zirconium. Concerning the location of getter material in a fuel element, the pellet-cladding gap and axial blanket region are potential options to avoid melting of titanium or obtaining a eutectic solution with MOX fuel. At the same time, an adequate temperature for oxidation as well as compatibilities with cladding material and fuel must be realized. Three options were proposed for titanium and their potentials were evaluated from this viewpoint. As a result, locating the titanium pellets in the upper axial blanket region of the fuel element was identified as the most promising option and it could provide the required low smear density titanium pellet.
Ebisawa, Hiroyuki; Hanakawa, Hiroki; Asano, Norikazu; Kusunoki, Hidehiko; Yanai, Tomohiro; Sato, Shinichi; Miyauchi, Masaru; Oto, Tsutomu; Kimura, Tadashi; Kawamata, Takanori; et al.
JAEA-Technology 2009-030, 165 Pages, 2009/07
JAEA-Technology-2009-030.pdf:69.18MB
The condition of facilities and machinery used continuously were investigated before the renewal work of JMTR on FY 2007. The subjects of investigation were reactor building, primary cooling system tanks, secondary cooling system piping and tower, emergency generator and so on. As the result, it was confirmed that some facilities and machinery were necessary to repair and others were used continuously for long term by maintaining on the long-term maintenance plan. JMTR is planed to renew by the result of this investigation.
Matsuyama, Shinichiro*; Ishii, Katsunori; Hirai, Mutsumi*; Tsuboi, Yasushi*; Kihara, Yoshiyuki
Journal of Nuclear Science and Technology, 44(3), p.317 - 322, 2007/03
Times Cited Count：0 Percentile：0.01(Nuclear Science & Technology)Japan Atomic Energy Agency has been developing vibro-packed fuel as one candidate for commercial fast breeder reactor fuels. In this study, vibro-packing experiments were carried out to investigate particle behavior during vibro-packing and particle distribution after vibro-packing in a cladding tube. Non-spherical uranium dioxide particles and spherical metallic uranium particles were used to simulate mixed oxide particles and oxygen getter particles. These experiments revealed that it is important to feed each size of fuel particles uniformly into a cladding tube without size segregation in order to obtain a vibro-packed fuel pin with oxygen getter particles uniformly dispersed. "Simultaneous feeding" with volumetric powder feeders is useful to obtain a vibro-packed fuel pin with oxygen getter particles uniformly dispersed.
with uranium particlesMatsuyama, Shinichiro; Ishii, Katsunori; Hirai, Mutsumi*; Tsuboi, Yasushi*; Kihara, Yoshiyuki
Proceedings of International Conference on Nuclear Energy System for Future Generation and Global Sustainability (GLOBAL 2005) (CD-ROM), 6 Pages, 2005/10
In the vipac fuel, it is considered that spherical metallic particles mainly consisting of uranium are added as an oxygen getter into vipac MOX fuel for FBR to prevent cladding inner corrosion by fuel-cladding chemical interaction (FCCI). In this study, vibro-packing experiments of granular UO particles and spherical metallic uranium particles and post-packing examinations such as destructive experiment were carried out. This study revealed that that it is important to feed particles uniformly into a cladding tube to obtain a vipac fuel with getter particles uniformly dispersed. Constant-volume feeder seems to be useful to obtain a vipac fuel with getter particles uniformly dispersed.
Compacts with/without Uranium ParticlesIshii, Tetsuya; Yuda, Ryoichi*; Hirai, Mutsumi*; Tsuboi, Yasushi*; Ukai, Shigeharu
Journal of Nuclear Science and Technology, 41(12), p.1204 - 1210, 2004/00
Times Cited Count：2 Percentile：17.18(Nuclear Science & Technology)The thermal conductivities of granular UO compacts with and without uranium particles were measured to evaluate the thermal performance of vibro-packed granular MOX fuels containing metallic fine particle oxygen getters. The thermal conductivity of the compact with 10wt.% of the uranium particles was higher than without uranium particles and after heating beyond 1408K, the melting point of the uranium particle, the thermal conductivity further increased..The evaluation model for analyzing such phenomena were developed and it was revealed that once the UO compact with the uranium particles was exposed to the temperature beyond 1408K, the uranium particle should melt and provide interconnect area between the UO granules and uranium particles, and between the uranium particles with each other. The resulting increase of the thermal conductivity was reasonably expressed by the effect of necks in the compact on the heat conduction.
*;
JNC TJ8400 99-075, 132 Pages, 1999/03
The design margin for uncertainties is evaluated by accumulating the uncertainties conservatively in the present LMFBR fuel design. However rationalization, such as reduction of design margin for uncertainties, is required to increase the linear heat rate and burn-up in the future. Probabilistic design method is considered to be effective to cut the excess design margin, because the design margin can be evaluated quantitatively by this method. In order to apply the probabilistic design method instead of present deterministic method, it is considered that the design criteria, design method and database should be provided. In the previous studies, the LWR statistic design method was investigated and BORNFREE-DIRAD and BORNFREE-STRESS were developed to apply the probabilistic fuel design method to evaluation of CDF, the cladding stress and the maximum fuel temperature. In this study, the database of material properties was investigated. The FP gas release ratio and FCCI (Fuel cladding chemical Interaction) related to evaluation of cladding stress were investigated based on irradiated data in JOYO and other foreign LMFBR. New correlation of FP gas release ratio and FCCI were proposed and their uncertainties were evaluated. These correlation were made as the function of various parameters such as linear heat rate and burn-up and the sensitivity of these parameter to the fuel performance were able to be evaluated by using these correlation. It was evaluated that the nominal FP gas release ratio by new correlation was smaller than that of old one, and uncertainty of new correlation was larger than that of old one. The 2 
-base values of cladding stress and CDF decreased comparing to these values evaluated by old correlation. It was shown that using new correlation could increase the burn-up. The necessity database for probabilistic method was clarified by above results.
*; *
PNC TJ9263 97-001, 108 Pages, 1997/03
Along the line of work of preparing unified cross-section library for demonstration fast breeder reactors, Monju criticality and control rod worth experimental data and their analysis were reviewed to evaluate experimental and analysis errors to apply the data in the cross-section adjustment work. The sensitivity coefficients of each cross-section for criticality and control rod worth were calculated by use of the generalized perturbation code SAGEP. The C/E values, experimental and analysis errors, and sensitivity coefficients are utilized in the adjustment of JENDL 3.2 in the other part of this series of work.
*; *; *; Ogawa, Toru; *; *; *; Saito, Hioraki*
Nuclear Technology, 89, p.183 - 193, 1990/02
Times Cited Count：29 Percentile：91.16(Nuclear Science & Technology)no abstracts in English
Morihira, Masayuki; Mizusako, Fumiki*; Tsuboi, Yasushi*
no journal, ,
A feasibility study for oxygen getter options is conducted in JAEA to reduce cladding inner corrosion of FBR MOX fuels to attain high burn-up. Investigation of oxygen getter loading options for pellet type MOX fuels as well as evaluation results of oxidation behavior of the candidate materials are reported.
