Formation behavior of gaseous iodine from sodium iodide under SFR severe accidental condition

Kikuchi, Shin; Kondo, Toshiki; Doi, Daisuke; Seino, Hiroshi; Ogawa, Kengo*; Nakagawa, Takeshi*

Proceedings of 14th International Topical Meeting on Nuclear Reactor Thermal-Hydraulics, Operation, and Safety (NTHOS-14) (Internet), 12 Pages, 2024/08

Flame structures and ignition thresholds of hydrogen jets containing sodium mist under various gas concentrations

Doi, Daisuke; Seino, Hiroshi; Miyahara, Shinya*; Uno, Masayoshi*

Journal of Nuclear Science and Technology, 59(2), p.198 - 206, 2022/02

https://doi.org/10.1080/00223131.2021.1961633

A Study on self-terminating behavior of sodium-concrete reaction

Kawaguchi, Munemichi; Doi, Daisuke; Seino, Hiroshi; Miyahara, Shinya

Journal of Nuclear Science and Technology, 53(12), p.2098 - 2107, 2016/12

https://doi.org/10.1080/00223131.2016.1199979

A sodium concrete reaction (SCR) is one of the important phenomena to cause the structural concrete ablation and the release of H gas in the case of sever accident of sodium cooled fast reactors. In this study, the long-time SCR test had been carried out to investigate the self-termination mechanism. The results showed the SCR terminated even if the enough amount of Na remained on the concrete. The quantitative data were collected on the SCR terminating such as temperature and H generation. The reaction products, which became the small solids in liquid Na were transferred with slurry state by generated H bubbles. Though the Na transfers actively and ablated the concrete surface with the high H generation rate, the mass exchange coefficient defined as decreased and the reaction products settled gradually with decreasing the H generation rate. Therefore, the Na concentration decreased at the reaction front and resulted in the SCR terminating naturally.

Development of fast reactor containment safety analysis code, CONTAIN-LMR, 3; Improvement of sodium-concrete reaction model

Kawaguchi, Munemichi; Doi, Daisuke; Seino, Hiroshi; Miyahara, Shinya

Proceedings of 23rd International Conference on Nuclear Engineering (ICONE-23) (DVD-ROM), 6 Pages, 2015/05

CONTAIN-LMR code is an integrated analysis tool to predict the consequence of severe accident in a liquid metal fast reactor. A sodium-concrete reaction is one of the most important phenomena, and Sodium-Limestone Concrete Ablation Model (SLAM) has been installed into the original CONTAIN code. The SLAM treats chemical reaction kinetics between the sodium and the concrete compositions mechanistically, the application is limited to the limestone concrete. In order to apply SLAM to the siliceous concrete which is an ordinary structural concrete in Japan, the chemical reaction kinetics model has been improved. The improved model was validated to analyze a series of sodium-concrete experiments which were conducted in Japan Atomic Energy Agency. It has been found that relatively good agreement between calculation and experimental results is obtained and the CONTAIN-LMR code has been validated with regard to the sodium-concrete reaction phenomena.

Multi-spin-state dynamics during insulator-metal crossover in LaCoO

Doi, Atsunori*; Fujioka, Jun*; Fukuda, Tatsuo; Tsutsui, Satoshi*; Okuyama, Daisuke*; Taguchi, Yasujiro*; Arima, Takahisa*; Baron, A. Q. R.*; Tokura, Yoshinori*

Physical Review B, 90(8), p.081109_1 - 081109_4, 2014/01

https://doi.org/10.1103/PhysRevB.90.081109

Monitoring for chemical property of muck from deep shaft

Kojima, Wataru; Yamakami, Mitsunori; Fujikawa, Daisuke; Orukawa, Go*; Kitagawa, Yoshito*; Doi, Takashi*; Saito, Ryosuke*

Doboku Gakkai Heisei-20-Nendo Zenkoku Taikai Dai-63-Kai Nenji Gakujutsu Koenkai Koen Rombunshu, p.453 - 454, 2008/09

no abstracts in English

Development of estimation technology for availability of measure for failure of containment vessel in sodium cooled fast reactor, 23; Numerical simulation of hydrogen combustion in containment vessel of fast reactor

Ito, Kei; Doi, Daisuke; Takata, Takashi; Uno, Masayoshi*

no journal, , 

Development of numerical simulation method of hydrogen combustion in containment vessel of fast reactor has been developed, in order to establish the estimation technology for availability of measure for failure of containment vessel in sodium cooled fast reactors. In this presentation, estimation results on influence of hydrogen combustion on the structure are reported based on the analysis by using numerical simulations.

Study on formation behavior of gaseous iodine during SFR severe accidents, 1; Overview of research and development

Seino, Hiroshi; Kondo, Toshiki; Doi, Daisuke; Kikuchi, Shin

no journal, , 

As part of the source term study for sodium-cooled fast reactors, we have focused on the formation behavior of gaseous iodine in the gas phase. As an overall overview, we will present the research program and the main progress until 2021.

Development of estimation technology for availability of measure for failure of containment vessel in sodium cooled fast reactor, 6; Numerical simulation method for hydrogen diffusion flame

Ito, Kei; Doi, Daisuke; Ohno, Shuji; Uno, Masayoshi*

no journal, , 

The authors have been developing a volume-of-fluid based numerical simulation method for hydrogen diffusion flame which may be generated under the severe accident condition of a sodium-cooled fast reactor. Here, the simulation strategy is briefly presented.

Development of estimation technology for availability of measure for failure of containment vessel in sodium cooled fast reactor, 4; Study on hydrogen combustion behavior in sodium aerosol containing atmosphere

Doi, Daisuke; Ito, Kei; Seino, Hiroshi; Miyahara, Shinya*; Uno, Masayoshi*

no journal, , 

no abstracts in English