The effect of TRISO particle size on its failure probabilities for UN and U 3 Si 2 fuel materials

In order to improve the security and increase the discharge burnup of the reactor, nuclear materials UN and U 3 Si 2 have been considered for their higher densities and breeding ratios compared with uranium dioxide. A specific modeling of Tristructural isotropic particles with UN and U 3 Si 2 as nuclear fuels was developed, and its failure probability was evaluated under irradiation conditions typical of a Molten Salt Reactor. The dimensional changes of the fuel particle kernel and layers were given. The stresses in the pyrolytic carbon and silicon carbide layers caused by the kernel gas pressure under normal operating conditions are calculated alone with the failure probability of the coated particle. The finding of this study will facilitate the development of new coated particulate fuels as well as support fuel parameters for design and construction of nuclear reactors.