Investigating new cladding material for NuScale reactor based on neutronic and thermo-mechanical properties using M5, E110, Zircaloy 4 and FeCrAl claddings

Nuclear fuel clads are among the most important components of a nuclear reactor. These clads are typically made of zirconium alloy; However these alloys do not possess the best thermo-mechanical properties. Therefore, in this study we attempted to achieve a clad with more suitable neutronic and thermo-mechanical properties by changing the clad materials used in the NuScale reactor. The changes in the material used in the reactor core cause a change in the effective multiplication factor as well as the length of the refueling interval. These effective multiplication factors and refueling period were obtained as the most important neutronic results within this research through simulating the NuScale reactor that uses the M5 cladding as a reference reactor and furthermore, the simulation of this reactor accommodating a clad change with three other types of common alloys, two of which are zirconium alloy and one of which is FeCrAl alloy. The results reveal that zirconium alloys in tandem with different thermo-mechanical properties are not much different in the neutronic matter of the core. In addition, FeCrAl alloy however endowed with excellent thermo-mechanical properties has a negative compact on the effective multiplication factor and the duration of the fueling period. Ultimately, in order to compensate for the negative effect of FeCrAl alloy on the neutronic properties, two solutions were used; The solution of using FeCrAl as a coating on a zirconium clad which presented outstanding neutronic results.