Large leakage sodium-water reaction accident analysis in a sodium-cooled fast reactor with paralleling steam generators

Abstract

In modern sodium-cooled fast reactor (SFR) designs, paralleling steam generators (SGs) are used to improve the economy. However, large leakage sodium-water reaction (SWR) models were developed only for designs using one SG. It is necessary to derive a pressure wave propagation model with parallel channels. Thus, a detailed pressure wave propagation model based on conversion equations was derived and verified with experimental data in this study. Using the developed model, a large leakage SWR accident in the SFR with four parallel SGs was simulated. The accident process was analyzed, and the design was verified to accommodate a large leakage SWR. Sensitivity analysis of critical parameters on large leakages was simulated and investigated. The SG pipe area, rupture disk bursting pressure, failure of the rupture disk, and release pipe area were found to have significant influences on the maximum pressure. Thus, the findings of this study are valuable for SG designs and protection from large leakage SWR accidents.