Measurement of Reaction Rates in Li/V-Alloy Assembly with 14 MeV Neutron Irradiation

To examine the accuracy in the neutronics calculations for the Li/V-alloy blanket system without Be neutron multiplier, a fusion neutronics experiment on a Li/V-alloy assembly has been performed with a 14 MeV neutron source. Reaction rates and tritium production rates (TPRs) in the assembly were measured with activation foils and Li₂CO₃ pellets. The measured reaction rates sensitive to fast neutrons agreed almost within ~10 % with ones calculated by using the MCNP5 code, JENDL-3.3 library and JENDL dosimetry file 99. Though there appeared a possibility of a significant underestimation in the transport calculations for the energy range of <~4 keV due to nuclear data of vanadium, the measured TPR was consistent with the calculated one within ~8 %.