Structural analysis of DEMO divertor cassette body and design study based on RCC-MRx

Highlights: • The last geometrical conception of the DEMO Divertor Cassette has been considered and the initial finite element model has been improved to obtain mapped mesh. The loads that really act on this component have been evaluated but at this stage of the analysis they have been applied as uniformly distributed because the values havent been supplied in a table-formatted manner. In spite of this simplification, the obtained results allow some useful deductions: the main role played by the thermal loads has been confirmed, and moreover the electric-magnetic loads (due to halo and eddy current) have been numerically obtained from the real DEMO Divertor geometry: they have been applied with the same uniform distribution and it seems that their action isnt really negligible. • Another simplified 2D fem model has been obtained and it supplies stress results that have the same order of magnitude of the aforementioned 3D model. • An early application of RCC-MRx design rule have also been considered:the component seems to be safe at least in nominal conditions. - Abstract: This paper refers to the activity of structural design of DEMO Divertor in the framework of the EUROfusion Consortium. The structural analysis and its preparatory assessments were carried on since a year and the first results were published in a previous paper. The Cassette Body has been examined considering the most conservatives loads (e.g. coolant pressure, volumetric nuclear heating and electro-magnetic loads) according to their latest estimates. This work is based on the design-by-analysis approach adopted in the conceptual design phase of the DEMO Divertor. This design activity has been focused on some key parameters e.g. loads, main geometric dimensions, positions of the Cassette attachments on the vacuum vessel, way of loads application to characterize the structural behavior of the Divertor Cassette. In addition to the existing 3D solid element model, a shell element model has also been developed: with this new model a parametric analysis can be done for a fast optimization. The structural assessment was done according to the Design and Construction Rules for Mechanical Components of Nuclear Installation (RCC-MRx).