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Deguchi, Yoshihiro*; Muranaka, Ryota*; Kamimoto, Takahiro*; Takagi, Taku*; Kikuchi, Shin; Kurihara, Akikazu
Applied Thermal Engineering, 114, p.1319 - 1324, 2017/03
Times Cited Count：2 Percentile：12.73(Thermodynamics)The purpose of this study aims to clarify the gas phase sodium-water reaction path and reaction products quantitatively. The counter-flow diffusion experiment device was employed to analyze the reaction path and reaction products using laser diagnostics. The main product of sodium-water reaction was determined to be NaOH and the sodium oxide was not notably measured compared with NaOH.
Deguchi, Yoshihiro*; Muranaka, Ryota*; Kamimoto, Takahiro*; Takagi, Taku*; Kikuchi, Shin; Kurihara, Akikazu
Proceedings of 3rd International Workshop on Heat Transfer Advances for Energy Conservation and Pollution Control (IWHT 2015) (CD-ROM), 6 Pages, 2015/10
The purpose of this study aims to clarify the gas phase sodium-water reaction path and reaction products quantitatively. The counter-flow diffusion experiment device was employed to analyze the reaction path and reaction products using laser diagnostics. The main product of sodium-water reaction was determined to be NaOH and the sodium oxide was not notably measured compared with NaOH.
Deguchi, Yoshihiro*; Takata, Takashi*; Yamaguchi, Akira*; Kikuchi, Shin; Ohshima, Hiroyuki
Mechanical Engineering Journal (Internet), 2(1), p.14-00029_1 - 14-00029_11, 2015/02
In a sodium-cooled fast reactor (SFR), liquid sodium is used as a heat transfer fluid because of its excellent heat transport capability. On the other hand, it has strong chemical reactivity with water vapor. One of the design basis accidents of the SFR is the water leakage into the liquid sodium flow by a breach of heat transfer tubes. This process ends up damages on the heat transport equipment in the SFR. Therefore, the study on sodium-water chemical reactions is of paramount importance for security reasons. This study aims to clarify the sodium-water reaction mechanisms using an elementary reaction analysis. From analytical results, the main reaction was Na + H
O = NaOH + H at gas-phase reaction.
Tamura, Kenta*; Deguchi, Yoshihiro*; Muranaka, Ryota*; Kusano, Koji*; Takata, Takashi*; Kikuchi, Shin; Kurihara, Akikazu
Proceedings of 24th International Symposium on Transport Phenomena (ISTP-24) (USB Flash Drive), 5 Pages, 2013/11
The purpose of this study aims to clarify the gas phase sodium-water reaction path and reaction products. The counter-flow diffusion experiment device is in the form of introducing the argon-based water vapor from the top of depressurized reaction chamber to the liquid sodium pool. Na, Na, HO, and reaction products in the counter-flow sodium-water reaction field were measured using laser diagnostics. The temperature controlled device was also improved to reduce the condensation of Na in the reaction zone for the better measurement performance. The main product in the sodium-water reaction was determined to be NaOH from the experimental results and its reaction path was discussed using Na-HO elementary reaction analysis.
Deguchi, Yoshihiro*; Tamura, Kenta*; Muranaka, Ryota*; Kusano, Koji*; Kikuchi, Shin; Kurihara, Akikazu
Reza Kenkyu, 41(11), p.927 - 931, 2013/11
In a sodium-cooled fast reactor (SFR), liquid sodium is used as a heat transfer fluid because of its excellent heat transport capability. On the other hand, it has strong chemical reactivity with water vapor. One of the design basis accidents of the SFR is the water leakage into the liquid sodium flow by a breach of heat transfer tubes. Therefore the study on sodium-water chemical reactions is of paramount importance for security reasons. This study aims to clarify the sodium-water reaction mechanisms using laser diagnostics. The measurement results show that the sodium-water reaction proceeds mainly by the reaction Na + HO = NaOH + H and the main product is NaOH from this reaction.
Deguchi, Yoshihiro*; Imanaka, Koichi*; Takata, Takashi*; Yamaguchi, Akira*; Kikuchi, Shin; Ohshima, Hiroyuki
Proceedings of 3rd Asian Symposium on Computational Heat Transfer and Fluid Flow (ASCHT 2011) (CD-ROM), 6 Pages, 2011/09
In a sodium-cooled fast reactor (SFR), liquid sodium is used as a heat transfer fluid because of its excellent heat transport capability. On the other hand, it has strong chemical reactivity with water vapor. One of the design basis accidents of the SFR is the water leakage into the liquid sodium flow by a breach of heat transfer tubes. This process ends up damages on the heat transport equipment in the SFR. Therefore, the study on sodium-water chemical reactions is of paramount importance for security reasons. This study aims to clarify the sodium-water reaction mechanisms using an elementary reaction analysis. As a result of the analysis, It was demonstrated that the main reaction is Na+HO 
NaOH+H as gas-phase reaction.
Ohshima, Hiroyuki; Yamaguchi, Akira*; Narabayashi, Tadashi*; Deguchi, Yoshihiro*
Dai-16-Kai Doryoku, Enerugi Gijutsu Shimpojiumu Koen Rombunshu, p.1 - 2, 2011/06
When a heat transfer tube is failed in a steam generator (SG) of a sodium-cooled fast reactor (SFR), pressurized water and/or water vapor leaks into liquid sodium surrounding the tube and forms a reacting jet with high temperature. This reacting jet might cause the secondary failure of adjacent heat transfer tubes due to wastage or over-heating tube rapture resulting in undesirable development of the accident. Therefore, the sodium-water reaction phenomenon (SWR) is one of most important issues for the design and safety assessment of SFRs. This paper describes the research and development plan of a new multi-physics numerical simulation system which is based on mechanistic and theoretical modeling of the SWR rather than empirical modeling and can contribute to detailed and quantitative evaluations of the SWR in any types of SGs including commercial SFRs.
Yamaguchi, Akira*; Takata, Takashi*; Ohshima, Hiroyuki; Sogabe, Joji*; Deguchi, Yoshihiro*; Kikuchi, Shin
Proceedings of 18th International Conference on Nuclear Engineering (ICONE-18) (CD-ROM), 8 Pages, 2010/05
Sodium-water reaction (SWR) is a design basis accident of a sodium fast reactor (SFR). A breach of the heat transfer tube in a steam generator (SG) results in contact of liquid sodium with water. The purpose of the present paper is to delineate the mechanism and process of the SWR by a counter-flow diffusion flame experiment and a numerical simulation.
Yamaguchi, Akira*; Takata, Takashi*; Ohshima, Hiroyuki; Deguchi, Yoshihiro*; Sakaba, Hiroshi*
no journal, ,
no abstracts in English
Sogabe, Joji*; Yamaguchi, Akira*; Takata, Takashi*; Ohshima, Hiroyuki; Kikuchi, Shin; Deguchi, Yoshihiro*
no journal, ,
no abstracts in English
Ohshima, Hiroyuki; Kurihara, Akikazu; Narabayashi, Tadashi*; Yamaguchi, Akira*; Takata, Takashi*; Deguchi, Yoshihiro*
no journal, ,
Development of a multi-physics numerical simulation system has begun in order to evaluate sodium-water reaction phenomena caused by heat transfer tube break in the large steam generator that will be adopted in the Japan Sodium-cooled fast breeder reactor. In this presentation, the R&D master plan will be introduced.
Deguchi, Yoshihiro*; Imanaka, Koichi*; Takata, Takashi*; Yamaguchi, Akira*; Kikuchi, Shin; Ohshima, Hiroyuki
no journal, ,
If the heat transfer tube in the steam generator of a sodium-cooled fast reactor is failed, high pressurized water vapor blows into the liquid sodium and the sodium-water reaction (SWR) takes place. Japan Atomic Energy Agency has been developing a multi-dimensional sodium-water reaction code for the analytical evaluation of this reaction. One of the items of code development is to construct the applicable chemical model for SWR. In this study, elementary reaction model has been developed for the purpose of identifying the dominant overall reactions for SWR. Also, we applied this model to the sodium-water counter-flow reaction field and evaluated the major reaction pathways.
Ohshima, Hiroyuki; Kurihara, Akikazu; Yamaguchi, Akira*; Takata, Takashi*; Narabayashi, Tadashi*; Deguchi, Yoshihiro*
no journal, ,
A new multi-physics numerical simulation system is being developed based on a 4-year R&D plan for the sake of the evaluation of sodium-water reaction phenomena, which are caused when a heat transfer tube is failed in a steam generator of a sodium-cooled fast reactor. 2-year study results are summarized as an interim report.
Tamura, Kenta*; Deguchi, Yoshihiro*; Suzuki, Koichi*; Takata, Takashi*; Yamaguchi, Akira*; Kikuchi, Shin; Ohshima, Hiroyuki
no journal, ,
In a sodium-cooled fast reactor (SFR), liquid sodium is used as a heat transfer fluid because of its excellent heat transport capability. On the other hand, it has strong chemical reactivity with water vapor. One of the design basis accidents of the SFR is the water leakage into the liquid sodium flow by a breach of heat transfer tubes. This process ends up damages on the heat transport equipment in the SFR. Therefore, the study on sodium-water chemical reactions is of paramount importance for security reasons. This study aims to clarify the sodium-water reaction mechanisms using laser diagnostics. Temperature, H, HO, OH, Na and Particulate matter were measured using laser induced fluorescence and CARS in the counter-flow reaction field. From the measured results, major gas-phase reaction of sodium-water reaction was identified.
Deguchi, Yoshihiro*; Tamura, Kenta*; Muranaka, Ryota*; Kitani, Taiyo*; Kusano, Koji*; Kikuchi, Shin; Kurihara, Akikazu
no journal, ,
It is a photograph of the sodium-water counter-flow diffusion flame formed by water vapor introduced to a liquid sodium pool. The orange part is the sodium emission (D line: 589 nm) emerged by sodium-water reactions, and the green part is the reaction products (NaOH etc.) and sodium fine particles visualized by a laser scattering method. By controlling the water vapor temperature, reaction products and sodium fine particles can be shaped like arms which boost up the sodium emission.
Ohshima, Hiroyuki; Kurihara, Akikazu; Narabayashi, Tadashi*; Yamaguchi, Akira*; Takata, Takashi*; Deguchi, Yoshihiro*
no journal, ,
When a heat transfer tube is failed in a steam generator (SG) of a sodium-cooled fast reactor (SFR), pressurized water and/or water vapor leaks into liquid sodium surrounding the tube and forms a reacting jet with high temperature. This reacting jet might cause the secondary failure of adjacent heat transfer tubes due to wastage or over-heating tube rapture resulting in undesirable development of the accident. Therefore, the sodium-water reaction phenomenon (SWR) is one of most important issues for the design and safety assessment of SFRs. We have been developing a new multi-physics numerical simulation system which is based on mechanistic and theoretical modeling of the SWR rather than empirical modeling and can contribute to detailed and quantitative evaluations of the SWR in any types of SGs including commercial SFRs. In this presentation, the whole R&D plan, three-year study results and future works will be introduced.
Muranaka, Ryota*; Deguchi, Yoshihiro*; Tamura, Kenta*; Takata, Takashi*; Kikuchi, Shin; Kurihara, Akikazu
no journal, ,
In a sodium-cooled fast reactor (SFR), liquid sodium is used as a heat transfer fluid because of its excellent heat transport capability. On the other hand, it has strong chemical reactivity with water vapor. One of the design basis accidents of the SFR is the water leakage into the liquid sodium flow by a breach of heat transfer tubes. Therefore, the study on sodium-water chemical reactions is of importance for security reasons. This study aims to clarify the gas phase sodium-water reaction path and reaction products. Na, Na, HO, and reaction products in the counter-flow sodium-water reaction field were measured using laser diagnostics such as Raman scattering and photo-fragmentation. The main product in the sodium-water reaction was determined to be NaOH and its reaction path was discussed using Na-HO elementally reaction analysis.
Deguchi, Yoshihiro*; Tamura, Kenta*; Muranaka, Ryota*; Kikuchi, Shin; Kurihara, Akikazu
no journal, ,
Sodium-water reaction (SWR) is a design basis accident of a sodium-cooled fast reactor (SFR). In a sodium-cooled fast reactor (SFR), liquid sodium is used as a heat transfer fluid because of its excellent heat transport capability. On the other hand, it has strong chemical reactivity with water vapor. One of the design basis accidents of the SFR is the water leakage into the liquid sodium flow by a breach of heat transfer tubes. This study aims to identify the dominant gas phase reaction of sodium-water reaction. The sodium-water, sodium-oxygen and sodium-hydrogen reaction fields were used to delineate the sodium-water reaction mechanism. These reactions were measured using laser diagnostics such as LIF, Raman scattering, Mie scattering, Absorption and Photo-fragmentation. Using these techniques, the sodium-water reaction mechanisms were discussed with consideration for elementary reactions.
Deguchi, Yoshihiro*; Tamura, Kenta*; Muranaka, Ryota*; Kusano, Koji*; Takata, Takashi*; Kikuchi, Shin; Kurihara, Akikazu
no journal, ,
In a sodium-cooled fast reactor (SFR), liquid sodium is used as a heat transfer fluid because of its excellent heat transport capability. One of the design basis accidents of the SFR is the water leakage into the liquid sodium flow by a breach of heat transfer tubes in a steam generator. Therefore the study on sodium-water chemical reactions is of paramount importance for safety reasons. This study aims to clarify the sodium-water reaction mechanisms using laser diagnostics. The sodium-water, sodium-oxygen and sodium-hydrogen counter-flow reactions were measured using laser diagnostics such as Raman, absorption and photo-fragmentation spectroscopies. The measurement results show that the main product of the sodium-water reaction is NaOH. The sodium-water reaction rate is slower than that of the sodium-oxygen reaction and hydrogen does not react noticeably with sodium.
Kikuchi, Shin; Kurihara, Akikazu; Ohshima, Hiroyuki; Deguchi, Yoshihiro*
no journal, ,
Elucidation research of chemical reaction mechanism for sodium-water reaction (SWR) has been performed to evaluate the failure of steam generator tube in sodium-cooled fast reactor. In this study, we evaluated the uncertainty of thermal analysis data for Verification and Validation (V&V) of analysis code.
