Neutronic and photonic analysis of the water-cooled Pb-17Li test blanket module for ITER-FEAT

Within the European Fusion Technology Program, the Water-Cooled Lithium Lead (WCLL) DEMO breeding blanket line was selected in 1995 as one of the two EU lines to be developed in the next decade, in particular with the aim of manufacturing a Test Blanket Module (TBM) to be implemented in ITER. This specific goal has been maintained also in ITER-FEAT program even if the general design parameters of the TBMs have reported some changes. This paper is focused on the investigation of the WCLL-TBM nuclear response in ITER-FEAT through detailed 3D-Monte Carlo neutronic and photonic analyses. A 3D heterogeneous model of the most recent design of the WCLL-TBM has been set-up simulating realistically its new lay out and taking into account 9% Cr martensitic steel as structural material. It has been inserted into an existing 3D semi-heterogeneous ITER-FEAT model accounting for a proper D/T neutron source. The analyses have been performed by means of MCNP-4C code running on a cluster of four workstations through the implementation of a parallel virtual machine. The main WCLL-TBM nuclear responses have been determined focusing the attention on power deposition density, material damage through displacement per atom (DPA) and He and H production rate, daily tritium production and tritium production rate radial distribution in the module. Moreover, the impact of using lithium at various Li6 enrichment on the TBM nuclear response has been investigated. The results obtained are herewith presented and critically discussed.