Eur. Phys. J. Plus (2020) 135: 233
https://doi.org/10.1140/epjp/s13360-020-00258-2

Regular Article

Nuclear data uncertainties for Swiss BWR spent nuclear fuel characteristics

¹ Reactor Physics and Thermal hydraulic Laboratory, Paul Scherrer Institut, Villigen, Switzerland
² Laboratory for Reactor Physics and Systems Behaviour, Ecole Polytechnique de Lausanne, Lausanne, Switzerland

^* e-mail: dimitri-alexandre.rochman@psi.ch

Received: 23 September 2019
Accepted: 30 January 2020
Published online: 7 February 2020

Abstract

The effect of nuclear data (fission yields, cross sections and emitted spectra) is quantified for spent nuclear fuel assemblies from a realistic boiling water reactor operated over 25 cycles. Nominal calculations are performed with the CASMO5, SIMULATE-3 and SNF codes and the ENDF/B-VII.0 nuclear data library. The uncertainties are calculated with the same codes, using a Monte Carlo propagation method, and the ENDF/B-VII.1 covariance matrices. The conclusions are that (1) the nuclear data have a non-negligible impact for spent fuel quantities (e.g., decay heat, neutron emission or isotopic contents); (2) the importance of varying all data together is demonstrated, showing an under- or overestimation of uncertainties if fission yields are sampled separately from the other nuclear data; and finally (3) the importance of considering the full irradiation history (multi-cycle assembly life) is also demonstrated, showing also an under- or overestimation of uncertainties when performing the nuclear data sampling for a single reactor cycle.