Experimental measurements and theoretical simulation of sodium combustion aerosol leakage through capillaries

Abstract

In severe accident of Sodium cooled Fast Reactors, containment would be pressurized due to release of radioactive materials and sodium which will form aerosols. These aerosols are released to environment through various leak pathways of containment (cracks, penetrations etc.). The time evolution of these aerosols hovered inside containment and its leakage is very much important for the realistic assessment of environmental source term. In this paper, studies regarding sodium aerosol leakage through capillaries as a function of pressure, aerosol concentration, humidity and dimensions of capillary are reported. Total leaked and plugged mass of aerosol and average leak rates are determined for various experimental conditions. A theoretical model representing the transport of aerosols through capillaries is developed, verified with the measured values and reasonable agreement is found. This work will aid in better understanding of phenomena important for the leakage of radioactive aerosol through cracks developed in severe accident of reactor.