抄録
Research of advanced types of burnable absorbers (BA) in nuclear fuel requires fast depletion code that would be able to calculate broad range of elements, nuclides or their combination. BAs compensate for the initial excess reactivity and consequently allow longer fuel cycles with higher fuel enrichments. Advanced types of BAs would increase fuel utilization by combining rapidly depleted BA like gadolinium with long-term effect of slowly-depleted BA like europium. State-of-art depletion codes require large amount of computational time, therefore, decision to develop fast depletion code was made. Currently developed U_WB_1 depletion code comprises of transport and burnup solver, both aiming to fast calculation of nuclear fuel depletion. In order to achieve low computational time, selected equations and data libraries describing fuel behavior was simplified, resulting in balanced accuracy and speed of the code. The paper describes validation calculations of Monte Carlo solver that is used in U_WB_1 depletion code. Reactor models with various fuel enrichment, fuel spectra and burnable absorbers were compared. Multiplication factor during fuel depletion and calculation figure of merit was compared. State-of-art MCNP6 code was used to calculate reference values.
