The Water-Cooled Lead–Lithium Breeding Blanket (WCLL BB) is one of the two blanket concept candidates to become the driver blanket of the EU-DEMO reactor. The design was enacted with a holistic approach. The influence that neutronics, thermal-hydraulics (TH), thermo-mechanics (TM) and magneto-hydro-dynamics (MHD) may have on the design were considered at the same time. This new approach allowed for the design team to create a WCLL BB layout that is able to comply with different foreseen requirements in terms of integration, tritium self-sufficiency, and TH and TM needs. In this paper, the rationale behind the design choices and the main characteristics of the WCLL BB needed for the EU-DEMO are reported and discussed. Finally, the main achievements reached during the pre-conceptual design phase and some remaining open issues to be further investigated in the upcoming conceptual design phase are reported as well.

A global thermal-hydraulic model of the EU DEMO tokamak, based on an object-oriented approach using the Modelica language, is currently under development at Politecnico di Torino. The first module of the global model will simulate the dynamics of the blanket cooling system and it will be able to investigate different coolant options and different cooling schemes, adapted to the different blanket systems currently under development in the Breeding Blanket project. Following the development of the module related to the Helium-Cooled Pebble Bed blanket, this paper presents the dynamic model of the Water-Cooled Lithium Lead (WCLL) blanket, designed at ENEA Brasimone, together with the first results obtained in steady-state condition