QUANTITATIVE ANALYSIS ON EFFECTS OF CAPTURE VOLUME OF THE REACTOR CAVITY DURING HIGH PRESSURE MELT EJECTION IN ULCHIN 3,4 UNITS

摘要

A method for the prediction of the debris dispersal fraction from the cavity with the capture volume during HPME is suggested and the dispersed fraction correlation is used with the latest version of CONTAIN code as one of the option for the debris dispersal fraction correlations. The dispersal fractions are evaluated for the various cavity configurations and the containment loading for Ulchin 3,4 plants during DCH is calculated. The results show that the effect of the capture volume on the debris dispersal into the containment was negligible when the reactor coolant system pressure is either high or low. For medium range of the pressure, however, the capture volume affects the release fraction of the debris from the cavity, which is decreased about 5% to 10 % depending upon the size of capture volume.