Study on eutectic melting behavior of control rod materials in core disruptive accidents of sodium-cooled fast reactors; Project overview and progress until JFY2022

Yamano, Hidemasa; Takai, Toshihide; Emura, Yuki; Fukuyama, Hiroyuki*; Nishi, Tsuyoshi*; Morita, Koji*; Nakamura, Kinya*; Pellegrini, M.*

Nihon Kikai Gakkai 2023-Nendo Nenji Taikai Koen Rombunshu (Internet), 5 Pages, 2023/09

A research project has been conducting thermophysical property measurement of a eutectic melt, eutectic melting reaction and relocation experiments, eutectic reaction mechanism investigation, and physical model development on the eutectic melting reaction for reactor application analysis in order to simulate the eutectic melting reaction and relocation behavior of boron carbide as a control rod material and stainless steel during a core disruptive accident in an advanced sodium-cooled fast reactor designed in Japan. This paper describes the project overview and progress until JFY2022.

Hybrid process combining solvent extraction / low pressure loss extraction chromatography for a reasonable MA(III) recovery process

Sano, Yuichi; Sakamoto, Atsushi; Miyazaki, Yasunori; Watanabe, So; Morita, Keisuke; Emori, Tatsuya; Ban, Yasutoshi; Arai, Tsuyoshi*; Nakatani, Kiyoharu*; Matsuura, Haruaki*; et al.

Proceedings of International Conference on Nuclear Fuel Cycle; Sustainable Energy Beyond the Pandemic (GLOBAL 2022) (Internet), 4 Pages, 2022/07

We developed a hybrid MA(III) recovery process combining MA(III)+Ln(III) co-recovery flowsheet by solvent extraction with TBP and MA(III)/Ln(III) separation flowsheet by simulated moving bed chromatography using HONTA impregnated adsorbents with large particle size porous silica support.

Study on eutectic melting behavior of control rod materials in core disruptive accidents of sodium-cooled fast reactors, 1; Project overview and progress until 2018

Yamano, Hidemasa; Takai, Toshihide; Furukawa, Tomohiro; Kikuchi, Shin; Emura, Yuki; Kamiyama, Kenji; Fukuyama, Hiroyuki*; Higashi, Hideo*; Nishi, Tsuyoshi*; Ota, Hiromichi*; et al.

Proceedings of 2020 International Conference on Nuclear Engineering (ICONE 2020) (Internet), 10 Pages, 2020/08

https://doi.org/10.1115/ICONE2020-16102

One of the key issues in a core disruptive accident (CDA) evaluation in sodium-cooled fast reactors is eutectic reactions between boron carbide (BC) and stainless steel (SS) as well as its relocation. Such behaviors have never been simulated in CDA numerical analyses in the past, therefore it is necessary to develop a physical model and incorporate the model into the CDA analysis code. This study focuses on BC-SS eutectic melting experiments, thermophysical property measurement of the eutectic melt, and physical model development for the eutectic melting reaction. The eutectic experiments involve the visualization experiments, eutectic reaction rate experiments and material analyses. The thermophysical properties are measured in a range from solid to liquid state. The physical model is developed for a severe accident computer code based on the measured data of the eutectic reaction rate and the physical properties. This paper describes the project overview and progress of experimental and analytical studies conducted until 2018. Specific results in this paper are boron concentration distributions of solidified BC-SS eutectic sample in the eutectic melting experiments, which would be used for the validation of the eutectic physical model implemented into the computer code.

Time-resolved soft X-ray imaging of femtosecond laser ablation process in metals

Tomita, Takuro*; Nishikino, Masaharu; Hasegawa, Noboru; Minami, Yasuo*; Takei, Ryota*; Baba, Motoyoshi*; Eyama, Tsuyoshi*; Takayoshi, Shodai*; Kaihori, Takeshi*; Morita, Toshimasa; et al.

Journal of Laser Micro/Nanoengineering, 9(2), p.137 - 142, 2014/06

https://doi.org/10.2961/jlmn.2014.02.0011

Femtosecond laser ablation processes on platinum, gold, and tungsten were observed by the single shot pump and probe reflective imaging using a soft X-ray laser probe. To avoid the timing error due to the jitter, we adopted a posteriori correction technique by simultaneous measurement of timing between the pump and probe pulses for every single shot, using a soft X-ray streak camera. A clear difference was found in the temporal behavior of the dynamical response of the soft X-ray reflectivity depending on the irradiated laser fluence in these three materials. On the other hand, the narrow dark rings were found in Pt and W, while an additional bright ring was found outside the dark disk in Au. Our result gives the experimental data comparable with various numerical simulations.

Analysis method of current distortion factor of 3-phase 3-wire system

*; Tanabe, Takeshi*; Naito, Masanobu*; Kubota, Yoshiki*; Morita, Tsuyoshi*; Kimura, Toyoaki; Matsukawa, Makoto; Miura, Yushi

Denki Gakkai Rombunshi, A, 119(3), p.279 - 285, 1999/03

no abstracts in English

Fast electron energy transport in solid target generated by high contrast high intense laser pulse

Tanimoto, Tsuyoshi; Nishiuchi, Mamiko; Mishima, Yosuke*; Kikuyama, Kenshiro*; Morioka, Tomoya*; Morita, Kiyoshi*; Kanasaki, Masato; Pirozhkov, A. S.; Yogo, Akifumi; Ogura, Koichi; et al.

no journal, , 

Development of high-level liquid waste conditioning technology for advanced nuclear fuel cycle, 21; Overall results and evaluation

Morita, Yasuji; Yamagishi, Isao; Sato, Soichi; Kirishima, Akira*; Fujii, Toshiyuki*; Uehara, Akihiro*; Tsukada, Takeshi*; Usami, Tsuyoshi*; Kurosaki, Ken*

no journal, , 

Development of high-level liquid waste (HLW) conditioning technology for advanced nuclear fuel cycle was conducted for the purpose of the reduction of potential problems in the verification process for HLW. It includes development of separation technology for Mo, Pd and Ru from HLW and development of separate treatment of the insoluble residue. The present report gives the overall results of the research and development and their evaluation. For the Mo separation, the extraction process with HDEHP was developed by performing continuous extraction tests and process simulation by a calculation code. An extraction process for Pd by 5,8-diethyl-7-hydroxy-6-dodecanone oxime was also developed, but was evaluated as less mature than the HEDHP process. As Ru separation method, volatilization of RuO after electrochemical oxidation was examined. Dissolution residue (metal alloy) and recovered Pd and Ru were solidified together by hot-press method.

Residual stress evaluation in linear friction welding of Ti alloy

Suzuki, Hiroshi; Akita, Koichi; Tsunori, Mitsuyoshi*; Nezaki, Koji*; Shinohara, Takahiko*; Kuroki, Hiroshi*; Morita, Ichiro*

no journal, , 

no abstracts in English

Extraction of trivalent lanthanoids into various ionic liquids having different anions

Eguchi, Ayano; Okamura, Hiroyuki; Sugita, Tsuyoshi; Ueda, Yuki; Morita, Kotaro*; Shimojo, Kojiro; Naganawa, Hirochika; Hirayama, Naoki*

no journal, , 

In this study, the effect of the hydrophobicity and structure of an ionic liquid (IL) anion on the extraction of trivalent lanthanoid ions (Ln(III) = La, Nd, Eu, Dy, Lu) using 2-thenoyltrifluoroacetone (Htta) was investigated. Four 1-butyl-3-methylimidazolium bis(perfluoroalkanesulfonyl)imides with different perfluoroalkyl (Rf) chain length (n=0, 1, 2, 4) were synthesized and used as the extraction solvent. The extraction selectivity of Ln(III) was in the order of Lu Dy Eu Nd La for all ILs. In addition, there was no significant difference in the extractability among ILs. The extracted species of each Ln(III) in these IL systems were investigated based on the slope of the plots of the logarithmic distribution ratio of Ln(III) as a function of aqueous phase pH. The results implied that the extracted species can be adjusted by Rf chain length of IL anions.

Study on eutectic melting behavior of control rod materials in core disruptive accidents of sodium-cooled fast reactors; Project overview and progress by JFY2017

Yamano, Hidemasa; Takai, Toshihide; Furukawa, Tomohiro; Saito, Junichi; Kikuchi, Shin; Emura, Yuki; Higashi, Hideo*; Fukuyama, Hiroyuki*; Nishi, Tsuyoshi*; Ota, Hiromichi*; et al.

no journal, , 

It is necessary to simulate a eutectic melting reaction and relocation behavior of boron carbide (BC) as a control rod material and stainless steel (SS) during a core disruptive accident in an advanced sodium-cooled fast reactor designed in Japan. On that account, a new project has been started to conduct eutectic melting experiments, thermophysical property measurement of the eutectic melt, and physical model development for the eutectic melting reaction. The eutectic experiments involve the visualization experiments, eutectic reaction rate experiments and material analyses. The thermophysical properties are measured in the range of liquid and solid states. The physical model is developed for a severe accident computer code based on the measured data of the eutectic reaction rate and the physical properties. This paper describes the project overview and progress by JFY2017.