Hydraulic modeling of a segment of the EU DEMO HCPB breeding blanket back supporting structure

The Helium-Cooled Pebble Bed (HCPB) concept for the Breeding Blanket (BB) of the EU DEMO tokamak reactor is under development at KIT within the EUROfusion consortium. Although the coolant distribution inside the blanket manifolds has been investigated in the past using 3D CFD models, such detailed analysis could not be extended to investigate the behavior of all blanket segments as a whole. Thus, for system-level analyses, lumped-parameter models are used, which exploit 0D/1D simplifications of the physics. This work presents the development of a 1D thermal-hydraulic (TH) model for the HCPB Back Supporting Structure (BSS). To validate such model, an experimental campaign is foreseen in 2018 in the HELOKA facility at KIT, in which a scaled-down mock-up of a segment of the BSS, which is dimensioned according to the facility working conditions, will be tested. Using the results of CFD simulations on full-size and mock-up, a first successful comparison between 3D and 1D results is presented. The 1D model is developed in such a way to allow a smooth integration in the GETTHEM code, which is under development at PoliTo, for the TH simulation of the entire tokamak.