Neutronics performance analysis on neutron consumption in a Fusion-Fission Hybrid System for tritium breeding

Abstract

Comparison evaluation of system performance for Fusion-Fission Hybrid System as a tritium supply facility to perform D-T fusion researches was conducted. Performances for neutron consumption as well as k-eff variation, energy multiplication, tritium breeding and waste transmutation were investigated. All neutronics calculations were conducted by MCNPX2.6.0 and MCNP6.1 with ENDF/b-VII.0 neutron cross-section library.Analysis results for tritium breeding modules show that tritium with module using water or FLiNaBe coolant is effectively produced due to softening effect in spite of low 6Li enrichment. When designing hybrid system for tritium breeding, design of the fuel zone between tritium breeding zones is beneficial for tritium breeding. In this case, 7 kg of tritium is more produced without degradation of transmutation compared to the design of fuel zone in front of the tritium breeding zone. In the comparison evaluation of performance on coolants options; PbBi, LiPb, Na and FLiNaBe, tritium with Li containing coolant is produced in the fuel zone, however amount of produced tritium in the tritium breeding zone is reduced due to low neutron economy. Performance of tritium breeding with softening flux is degraded, since neutron economy is reduced by increasing the capture reaction.