Utilization of Ceramic Uranium Fuels in ARIES-RS Fusion Reactor

This study presents the neutronic performance of the ARIES-RS fusion reactor design using different natural ceramic uranium fuels, namely UO₂, UN or U₃Si₂, dispersed in graphite matrix. These fissionable fuels inserted as micro spheres into the first range quadratic channels at the immediate neighborhood of the first wall in the inboard blanket to amplify fusion power and breed fissile fuel. Neutron transport calculations were performed with the help of the SCALE4.3 system by solving the Boltzmann transport equation with the XSDRNPM code in 238 neutron groups and a S₈–P₃ approximation. Among the investigated fuels, UN showed the best neutronic performance while UO₂ and U₃Si₂ had similar performances. Numerical results pointed out that inserting fissionable fuel zone even with a small thickness (10 cm) in a pure fusion reactor increased fusion power from 2170 MW to 4500, 5250 and 4150 MW depending on the fuel type. Furthermore significant amount of fissile fuel was produced to be charged to light water reactors.