Neutronics assessment of thorium-based fuel assembly in SCWR

•A novel thorium-based fuel assembly for SCWR has been introduced and investigated.•Neutronic properties of three thorium fuels have been studied, compared with UO2 fuel.•The thorium-based fuel has advantages on fuel utilization and lower MAs generation.

Aiming to take advantage of neutron spectrum of SCWR, a novel thorium-based fuel assembly for SCWR is introduced in this paper. The neutronic characteristics of the introduced fuel assembly with three different thorium fuel types have been investigated using the “dragon” codes. The parameters in different working conditions, such as infinite multiplication factors, radial power peaking factor, temperature coefficient of reactivity and their relation with the operation period have been assessed by comparing with conventional uranium assembly. Moreover, the moderator-to-fuel ratio (MFR) was changed in order to investigate its influence on the neutronic characteristics of fuel assembly. Results show that the thorium-based fuel has advantages on both efficient fuel utilization and lower minor actinide generation, with some similar neutronic properties to the uranium fuel.