ARIES-ACT2 DCLL Power Core Design and Engineering

ARIES-ACT2 is a conventional tokamak power plant conceptual design that uses a dual-coolant lead-lithium (DCLL) blanket concept with a RAFS (reduced-activation ferritic steel) first-wall (FW) and blanket structure. The design concept is the first fully integrated study of the DCLL blanket in a tokamak power plant. The major engineering efforts were to develop a credible configuration that can meet aggressive maintenance goals and achieve high availability and maintainability; to design a DCLL blanket that can meet tritium breeding requirements with reasonable helium and Pb-17Li cooling schemes to remove the surface and volumetric thermal power in the blanket while keeping the helium pressure drop, magnetohydrodynamic (MHD) pressure drop, and total pumping power low, and material temperatures and stresses at an acceptable level; to design manifolding and access pipes to connect/disconnect the inboard and outboard blanket sectors to the ring headers located underneath the reactor without affecting maintenance operations and creating major MHD effects when feeding all the Pb-17Li/He mass flow. Detailed three-dimensional finite element analysis of the DCLL blankets together with design iterations have been performed to finalize and optimize the major design parameters of the FW and blanket structure. The helium-cooled W plate-type divertor concept was adopted and integrated into the ACT2 DCLL power core to accommodate the peak surface heat flux of ∼10 MW/m² predicted by edge plasma physics.