Helium-cooled lithium lead: Activation analysis of the test blanket module in ITER

Abstract The helium-cooled lithium lead (HCLL) test blanket module (TBM) is one of the European blanket concepts selected to be tested in ITER. The test is an important step towards the development of DEMO blankets. Nuclear analysis of the TBM has been performed using the MCNP-4C Monte Carlo code, supported with FENDL-2 nuclear data library. Neutron fluxes were calculated with MCNP in LiPb breeder units and in the EUROFER cooling plates in various positions inside the module for a 500-MW fusion power. The activation calculations were performed using FISPACT (EASY 2005.1 package): activity, decay heat and contact dose rate were calculated inside the TBM using as input the neutron fluxes calculated by MCNP. The results of the activation analysis in terms of activity, decay heat and dose rate at different times since shut-down till 10 6 years after at various radial, poloidal and toroidal positions are presented. The effect of impurities on LiPb and EUROFER as well as the impact of the different irradiation scenarios on the activation of TBM has been investigated and discussed.