Monte Carlo calculations of the nuclear effects of certain fluids in a hybrid reactor

• It was investigated effects on neutronic measurements of certain fluids in the system.
• It was used MCNPX-2.7.0 Monte Carlo code for three-dimensional calculations.
• It was found that neutronic calculations desirable values for 85% Li20Sn80 + 5% SFG-PuO2 + 10% UO2, NpO2, UCO.

This study analyzes the effects of certain heavy-metal-salt fluids on nuclear parameters in a fusion–fission hybrid reactor. Calculated parameters include the tritium breeding ratio (TBR), energy multiplication factor (M), heat deposition rate, fission reaction rate, and fissile fuel breeding in the reactor's liquid first wall, blanket, and shield zones; gas production rates in the structural material of the reactor were calculated, as well. The fluid mixtures consisted of 93–85% Li20Sn80 + 5% SFG-PuO2 and 2–10% UO2, 93–85% Li20Sn80 + 5% SFG-PuO2 and 2–10% NpO2, and 93–85% Li20Sn80 + 5% SFG-PuO2 and 2–10% UCO. The fluids were used in the liquid first wall, blanket, and shield zones of a fusion–fission hybrid reactor system. A 3 cm wide beryllium (Be) zone was used for neutron multiplier between the liquid first wall and the blanket. The structural material used was 9Cr2WVTa ferritic steel, measuring 4 cm in width. Three-dimensional analyses were performed using the Monte Carlo code MCNPX-2.7.0 and the ENDF/B-VII.0 nuclear data library.