Structural assessment of the EU-DEMO water-cooled lead lithium central outboard blanket segment adopting the sub-modelling technique

The development of a sound conceptual design the Water-Cooled Lead Lithium Breeding Blanket (WCLL BB) is pivotal to make breakthrough towards selection driver blanket concept for EU-DEMO. To achieve this goal, an intense research campaign has been performed at University Palermo, in cooperation with ENEA Brasimone, under umbrella EUROfusion. In paper, structural analyses different poloidal regions WCLL BB Central Outboard (COB) segment are reported. particular, starting from results thermo-mechanical analysis whole COB segment, sub-modelling technique applied most significant regions, located top, middle and bottom segment. aim focus on stress field locally arising purposely selected steady-state nominal accidental loading scenarios. operating conditions, as well scenarios derived both in-box LOCA Vertical Plasma Disruption accidents have considered. Thanks approach, deformative action entire can be imposed boundaries each local model realistically assess its performances. Moreover, reproduces details not included global one, such Segment Box (SB) cooling channels. Then, behaviour assessed compliance RCC-MRx code. obtained highlighted that predicted by similar calculations within Stiffening Plates, whereas application must investigate detail SB addition, indicate attachments should revised, they contribute produce large deformation originating excessive stresses, mainly equatorial region.