Extension and validation of aerosol wash-down model on inclined wall

Abstract

During severe accidents, fission products as aerosols are released into the containment and consequently deposited on walls. The condensate flow on walls could wash the deposited aerosols downwards to the sump. The aerosol wash-down process on walls is significant to evaluate radiative source term distribution in nuclear containment. In this paper, the aerosol wash-down model AULA is extended to be valid for inclined walls and cohesive aerosols. Moreover, the condensate coverage is coupled to calculate the aerosol mass washed down by the condensate flow. A correlation of condensate coverage is proposed and validated against experimental data. In order to improve the dimensionless critical shear stress model, a correction factor, which considers wall inclination and aerosol cohesion, is deduced by the force analysis. The extended aerosol wash-down model is validated against the THAI-AW3-LAB experiment. The results comparison show generally good agreements. Furthermore, the model characteristics under severe accident conditions and the analyses on parameters, such as aerosol density, diameter, and inclination are presented and discussed.