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Ohshima, Hiroyuki; Morishita, Masaki*; Aizawa, Kosuke; Ando, Masanori; Ashida, Takashi; Chikazawa, Yoshitaka; Doda, Norihiro; Enuma, Yasuhiro; Ezure, Toshiki; Fukano, Yoshitaka; et al.
Sodium-cooled Fast Reactors; JSME Series in Thermal and Nuclear Power Generation, Vol.3, 631 Pages, 2022/07
This book is a collection of the past experience of design, construction, and operation of two reactors, the latest knowledge and technology for SFR designs, and the future prospects of SFR development in Japan. It is intended to provide the perspective and the relevant knowledge to enable readers to become more familiar with SFR technology.
Sekine, Yurina; Fukazawa, Tomoko*; Aizawa, Mamoru*; Kobayashi, Riki*; Chi, S.*; Fernandez-Baca, J. A.*; Yamauchi, Hiroki; Fukazawa, Hiroshi
Journal of Physical Chemistry B, 118(47), p.13453 - 13457, 2014/08
Times Cited Count:2 Percentile:3.76(Chemistry, Physical)Neutron diffraction patterns for deuterated poly-,,-dimethylacrylamide (PDMAA) hydrogels were measured from 10 to 300 K to investigate the structure and properties of water in the gels. Diffraction peaks observed below 250 K indicate the existence of ice in the hydrogels. Some diffraction peaks from the ice are at lower diffraction angles than those in ordinary hexagonal ice (Ih). These shifts in peaks indicate that the lattice constants of the and axes in the ice are about 0.29% and 0.3% higher than those in ice Ih, respectively. The results show that bulk low-density ice can exist in PDMAA hydrogels. The distortions in the lattice structure of ice imply significant interactions between water molecules and the surrounding polymer chains, which play an important role in the chemical and mechanical properties of the hydrogel.
Fukazawa, Tomoko*; Ikeda, Naohiro*; Tabata, Mayu*; Hattori, Masataka*; Aizawa, Mamoru*; Yunoki, Shunji*; Sekine, Yurina
Journal of Polymer Science, Part B; Polymer Physics, 51(13), p.1017 - 1027, 2013/07
Times Cited Count:32 Percentile:74.42(Polymer Science)Aizawa, Kosuke; Chikazawa, Yoshitaka; Usui, Shinichi; Konomura, Mamoru; Ando, Masato*
JAEA-Research 2007-042, 105 Pages, 2007/06
Various conceptual design studies of sodium cooled small reactor have been performed in the feasibility study. In FY2005 study, a 300MWe modular reactor which adopts metal-fueled and 1 loop cooling system in order to pursues economical competitiveness was investigated. Transient analyses were performed to show core safety under the large pipe break accident that was found to be the severest accident in case of a 1 loop cooling system. From the analysis results, it was showed a possibility to maintain the core safety without the reactor scram. Transient analyses of the natural circulation decay heat removal system were also performed, and it was showed a possibility to maintain the core safety after the reactor scram. The in-vessel storage (IVS) was adopt to eliminate the ex-vessel storage and the design of the distribution flow adjustment device in IVS is studied. It was showed that the IVS could be introduced without modifying in the reactor design in FY2004. The rationalization of the fuel handling system is investigated taking advantage of co-location plant in which the reactor, the recycle plant and the fuel fabrication plant are co-located in a site. As a result of rationalization, the volume of the reactor building becomes 0.85 times as much as that of the design in FY2004.
Chikazawa, Yoshitaka; Aizawa, Kosuke; Konomura, Mamoru
JAEA-Research 2006-007, 114 Pages, 2006/03
In the feasibility study of commercialized fast reactor cycle systems of JAEA, we make a concept of a sodium cooled reactor without secondary sodium circuits. And a sodium cooled reactor with Cu bonded steam generator is one of promising concept has been investigated. In the FY2004 study, pressurized tube experiments using the 33 array specimen imitated the reference tube geometry are carried out aiming to clarify crack propagation behavior in the reference steam generator. Compared with the results of the bend experiments in the FY2003, it is understood that the crack initiation and the crack propagation are greatly obstructed by the effect of the specimen shape. The reference tube geometry was optimized to pursue the economic. As a result of optimization, the construction cost of reactor cooling system with Cu bonded steam generators is 0.7 times as much as that of an ordinary sodium cooled reactor with secondary sodium circuits. Condition for crack propagation in the reference tube geometry is analyzed by using the result of the bend experiments in the FY2003. From the results of the bend experiments and the analysis, it was understood that there was a possibility that the crack reaches the Cu layer. But, when the crack reaches the Cu layer, it was shown that the crack propagation stopped.
Chikazawa, Yoshitaka; Aizawa, Kosuke; Konomura, Mamoru; Ara, Kuniaki
JNC TN9400 2005-044, 86 Pages, 2005/08
In the feasibility study of JNC, an intermediate heat exchanger with a mechanical pump aiming to reduce material mass and floor area has been investigated. In this study, as an alternative of the intermediate heat exchanger with a mechanical pump, adaptability of an intermediate heat exchanger with electro magnetic pumps is investigated.An intermediate heat exchanger with electro magnetic pumps for a medium scale sodium cooled reactor is designed. An electromagnetic analysis is performed to determine basic specifications of electro magnetic pumps. A 3-D flow analysis shows the flow stability of the electro magnetic pump outlet and the importance of flow guide.Furthermore, a magnetic field analysis of an electro magnetic flow meter is performed, it is confirmed possibility to apply the flow meter to the main cooling system.
Chikazawa, Yoshitaka; Aizawa, Kosuke; Konomura, Mamoru; Shimakawa, Yoshio*; Sawa, Naoki*; Ando, Masato*
no journal, ,
no abstracts in English
Aizawa, Kosuke; Chikazawa, Yoshitaka; Konomura, Mamoru; Usui, Shinichi; Sherwood, D. V.*
no journal, ,
no abstracts in English