Uncertainty quantification for a severe accident sequence in a SFP in the frame of the H-2020 project MUSA: First outcomes

The Management and Uncertainties of Severe Accidents (MUSA) project, funded in HORIZON 2020 coordinated by CIEMAT (Spain), aims at consolidating a harmonized approach for the analysis uncertainties sensitivities associated with (SAs) focusing on Source Term (ST). In this framework, objectives Innovative Spent Fuel Pool (IMSFP – WP6), led IRSN (France), are to quantify rank affecting accident analyses (SFP), review existing contemplated SA management measures systems assess their possible benefits terms reduction radiological consequences. To propagation input parameters output severe codes (ASTEC, MELCOR, RELAP/SCDAP), diverse set uncertainty quantification (UQ) tools (DAKOTA, RAVEN, SUNSET, SUSA) used. statistical framework used different UQ-tools is similar e.g. pure random (Monte Carlo) Latin hypercube sampling (LHS). Fourteen partners from three world regions involved WP6 activities. target paper describe achievements during first years project. part, description given SFP accidental scenario, key variables radionuclides chosen as ST Figures Merit (FoM) identified sources models parameters. A element when defining scenario has been consideration (or not) reactor building, it expected significantly affect analyses. second insights coming out calculation phase project presented. also exposed, well whose will be assessed Finally, challenges that arise such an exercise discussed, major difficulties found applying UQ methodologies scenarios solutions adopted.