Effect of different description of neutron source models on neutronics calculation of CFETR

Abstract Background: In Tokamak experiment device, the 14-MeV high-energy neutrons which D-T fusion reaction releases may cause a series of problems such as material activation, high thermal loading and so on when they contact surrounding parts, so the relative neutronics calculation in the process of blanket design and optimization is particularly important. Purpose: This study aims to analyze the effect of point source, uniform source, neutron source based on L-mode, H-mode, A-mode respectively on different neutronics calculation. Methods: Using MCNP (Monte Carlo N Particle Transport Code) program based on the Monte Carlo method the neutron transport process is simulated and the effect of different neutron source models is calculated. Results: Different descriptions of neutron source models have less influence on tritium breeding ratio, but obvious effects on neutron wall loading and power density distribution. Conclusion: Therefore, proper neutron source model should be applied to calculate different neutronics. (authors)