In the framework of the extension of the operating life of the nuclear powerplants, EDF is regularly called to reassess the adequacy of the design provisions with regard to safety. Concerning the radiological consequences in case of a severe accident, the safety demonstration studies consider that in the presence of cracks in the containment, all the radionuclides are released through the containment. In order to better assess the margins provided by this assumption, EDF addresses this study to obtain a better knowledge about the pathway of radionuclides within the cracked concrete in the event of a severe accident and to estimate the retention rate of radionuclides present in the form of aerosols, according to their type and flow conditions.
The objective of the study is to design, prototype and validate a laboratory-scale test model dedicated to the migration of radioactive aerosols under high temperature (until ~ 150°C) and pressure (until 4 bars in relative) conditions through a cracked concrete specimen.