The VANAM experiments M1 and M2— test results and multi-compartmental analysis

Abstract To model the phenomena occurring in a reactor containment during a severe accident, a new generation of computer codes has been developed which enable simultaneous analysis of thermal hydraulics and aerosol behaviour in a multi-compartment geometry. The VANAM experiments in the 630-m3 Battelle model containment are being performed to verify these codes, in particular the GRS code FIPLOC-M. The experimental results obtained so far reveal distinct multi-compartment effects like inhomogeneous steam-air-aerosol distribution and enhanced local aerosol depletion by volume condensation. Analyses with the FIPLOC-M code show the possibilities of adequately modeling those effects.