Numerical investigation of sodium-water reaction phenomenon in a tube bundle configuration

A numerical investigation of sodium-water reaction (SWR) phenomenon under a tube bundle configuration was carried out in order to evaluate characteristics of the reacting zone in an area nearby the leakage, such as distributions of the gas volume fraction, the temperature and the concentration of the sodium compounds, as well as to evaluate an applicability of the numerical methodology that has been developed in the previous authors work to a complicated flow path. SWAT-1R experiment, in which 43 tubes were placed in a zigzag alignment and water vapor leaked vertically upward from the bottom center of the bundle, was chosen as a benchmark problem. As a result of the numerical investigation, it was demonstrated that one can predict the SWR phenomenon with a complicated pin bundle configuration numerically. In addition, it was also demonstrated that numerical quantification of a secondary failure possibility due to over-heating rupture was to be achieved using the present result. (authors)