Study on sodium-water reaction phenomena in steam generator of sodium-cooled fast reactor, 37; Applicability of mechanistic numerical method to actual condition

Uchibori, Akihiro ; Ohshima, Hiroyuki

A mechanistic computer program called SERAPHIM to calculate compressible multicomponent multiphase flow with sodium-water chemical reaction has been developed as one of the evaluation methods for heat transfer tube failure accident in a steam generator of sodium-cooled fast reactors. In this study, applicability of the SERAPHIM program was investigated through the analysis of the experiment on water vapor discharging into liquid sodium under the actual condition of the steam generator. The water vapor under expanded jet reacting with the ambient liquid sodium appeared in the numerical result. The high-velocity region of the entrained liquid droplets was formed around the jet. The impingement position of the liquid droplets on the target tube located above the water vapor discharging tube agreed with the position of the wastage mark confirmed in the experiment. The temperature distribution measured around the reacting jet was also successfully reproduced by the SERAPHIM program.