Malovytsia M. Power control of the perspective fast reactor that works in the self sustained nuclear burning wave mode

The thesis deals with the theoretical study of the possibility of the power control of the perspective fast reactor that works in the self sustained mode of the nuclear burning wave (NBW). In our study the power is controlled by means of the radial neutron reflector. The study was conducted by simulating the nuclear burning wave propagation along the axial direction of the cylindrical reactor with U Pu fuel cycle and Pb Bi eutectics as coolant and radial neutron reflector. The deterministic approach based on the numerical solution of the problem of the neutron transport in the multiplication medium, with constantly changing isotope composition, was used for simulation of the nucleus neutron processes in such reactor. The isotope composition is changing self consistently due to the nuclear transmutations, according to the corresponding equations of the fuel elements burnup. The mathematical model consisted of the set of non stationary non linear diffusion of neutrons in the reactor medium equations, the fuel elements burnup equations and the nuclear kinetics of the delayed neutron precursor equations while using multigroup nuclear constants (26 energy group approximation) to account for energy dependence of the according cross sections.