UNCERTAINTIES ASSOCIATED WITH NUCLEAR DATA WHEN CALCULATING FUEL ISOTOPE CONCENTRATIONS AT BURNUP
29th Symposium of AER on VVER Reactor Physics and Reactor Safety (2019, Energoland, Mochovce NPP, Slovakia)
spent fuel disposal and actinide transmutation
Abstract
UNCERTAINTIES ASSOCIATED WITH NUCLEAR DATA WHEN CALCULATING FUEL ISOTOPE CONCENTRATIONS AT BURNUP
Pavel Mikoláš
ŠKODA JS a.s., Orlík 266/15, 316 00 Pilsen, Czech Republic
The programs used to determine isotope concentrations in spent nuclear fuel use a multi-group transport approach. Cross-sections and other variables are prepared for multi-group libraries for these programs, which are based on basic nuclear data. These nuclear data cannot be determined accurately, they always have some uncertainty.
The paper shows, on a concrete example, the effect of these uncertainties on the determination of concentrations of selected isotopes in spent fuel by comparison with experimentally determined values of these concentrations.
It is shown that the effect of nuclear data uncertainties is different for different isotopes, and in some cases it is quite considerable.