Statistical Analysis of NPP transients: LBLOCA in a PWR; Parametric, non-parametric methods and EBEPU

The Best Estimate Plus Uncertainty (BEPU) approach is being used worldwide for nuclear power plants licensing. This method relies on the use of best estimate models to simulate sequences, evaluating the uncertainties involved. To assess these uncertainties, several methodologies have been developed such as the non-parametric Wilks/Wald method, parametric methods that reconstruct a distribution from the data, or the binomial approach. Additionally, sensitivity analyses can be performed to obtain the correlation of the output-inputs. Finally, a variability analysis of the most influential parameters is made to find a combination of parameters that can lead to damage is also useful. In this seminar, all previous techniques are described, studied and applied by performing a large Monte Carlo set of simulations of a loss of coolant accident in a PWR assessing two figures of merit. Finally, some remarks will be provided on how to employ BEPU coupled with PSA in the new approach of Extended-BEPU (EBEPU).