Study on sodium-water reaction phenomena in steam generator of sodium-cooled fast reactor, 22; Overview of three-year study results

Ohshima, Hiroyuki; Kurihara, Akikazu ; Narabayashi, Tadashi*; Yamaguchi, Akira*; Takata, Takashi*; Deguchi, Yoshihiro*

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.