Nuclear data uncertainties propagation methods in Boltzmann/Bateman coupled problems: Application to reactivity in MTR

作者：Frosio Thomas^*; Bonaccorsi Thomas; Blaise Patrick

来源：Annals of Nuclear Energy, 2016, 90: 303-317.

DOI：10.1016/j.anucene.2015.12.010

• Uncertainty propagation
• Nuclear data
• Transport
• Depletion
• Sensitivity analysis
• Reactivity

A novel method has been developed to calculate sensitivity coefficients in coupled Boltzmann/Bateman problem for nuclear data (ND) uncertainties propagation on the reactivity. Different uncertainty propagation methodologies, such as One-At-a-Time (OAT) and hybrid Monte-Carlo/deterministic methods have been tested and are discussed on an actual example of ND uncertainty problem on a Material Testing Reactor (MTR) benchmark. Those methods, unlike total Monte Carlo (MC) sampling for uncertainty propagation and quantification (UQ), allow obtaining sensitivity coefficients, as well as Bravais-Pearson correlations values between Boltzmann and Bateman, during the depletion calculation for global neutronics parameters such as the effective multiplication coefficient. The methodologies are compared to a pure MC sampling method, usually considered as the "reference" method. It is shown that methodologies can seriously underestimate propagated variances, when Bravais-Pearson correlations on ND are not taken into account in the UQ process.

• 出版日期2016-4
• 单位中国地震局