The 3 x D neutronics calculation of the 2 x 6 CH HCSB TBM

The neutronics calculations for the new 2 x 6 CHSB TBM model have been performed with the Monte Carlo code MCNP/4C, and nuclear cross-section data from the FENDL-2.0 data library. A 20 degree torus sector model, which is consisted of CHSB TBM and the ITER-FEAT, forms the basis of the neutronics calculations. Typically 2 million source neutron histories were tracked in the MCNP calculations to ensure a sufficient statistical accuracy for the calculated nuclear responses. In the calculation, Li4SiO4 (80 at % Li-6 enrichment) is as Breeder material, and EUROFER as structural material. In order to improve the distribution of power density in the blanket module, the arrangement of the Be neutron multiplier in the breeding zone has been optimized. Binary Be pebbles with diameters 0.5 mm and 1 mm were chosen for the bed. The power density distribution has been calculated in the poloidal zones of the TBM. A peak power density of 6.26 MW/m3 under an average neutron wall loading of 0.78 MW/m2 occurs at the end of first wall. Total energy deposition in HCSB TBM is 0.587 MW. The tritium generated amounts to about 0.0123 g/d under the ITER standard operation condition. (authors)