RAVEN/OSCAR-Fusion coupling for activated corrosion products assessments, sensitivity, and uncertainty quantification

Activated corrosion products (ACPs) may represent a significant source of radiological hazards in nuclear fusion reactors. Corrosion and erosion phenomena mobilize activated materials which are transported by the working fluid in regions of the cooling system accessed by worker personnel. Predicting contaminant transport in tokamak cooling circuits may benefit radiation exposure assessment, design optimization, waste management, maintenance plan definition, and source terms identification. Several calculation tools have been made available for ACP determination in nuclear systems. Among these, the OSCAR-Fusion code, developed by the CEA (France), allows for predicting ACP generation and transport in closed water-cooled loops for fusion applications. This work aims to show a straightforward sensitivity analysis methodology and uncertainty quantification (UQ). A single ACP assessment involves several neutronics, thermal-hydraulics, geometrical, and water chemistry parameters. Coupling OSCAR-Fusion to RAVEN, a multipurpose framework developed by INL (USA), allows sensitivity and UQ analyses that might provide useful indications to the designers and safety analysts. This work presents a general methodology, showing preliminary results obtained for the EU-DEMO divertor cassette primary heat-transfer systems.