Uncertainty Quantification of LWR Core Characteristics Using Random Sampling Method

Abstract Uncertainties of various neutronics characteristics in commercial boiling water reactor (BWR) and pressurized water reactor (PWR) cores due to cross-section covariance are evaluated by the Latin Hypercube Sampling (LHS) method, which is an efficient random sampling algorithm. Thermal-hydraulic feedback and burnup effects are fully and explicitly taken into account using a licensing-grade core simulator. Uncertainties for various core characteristics are evaluated by the statistical processing of core calculation results based on the LHS method. The calculation results indicate that uncertainty of critical eigenvalue (i.e., core reactivity) in the BWR core is comparable to that of a typical PWR core. On the other hand, uncertainties of assembly relative power distribution and maximum assembly burnup in the present BWR core are much smaller than those of the present PWR core. The strong thermal-hydraulic feedback effect in the BWR core significantly contributes to the difference of uncertainties in BWR and PWR cores.

[1]  Bradley T Rearden,et al.  A Statistical Sampling Method for Uncertainty Analysis with SCALE and XSUSA , 2013 .

[2]  N. H. Larsen Core design and operating data for Cycles 1 and 2 of Peach Bottom 2 , 1978 .

[3]  R.E. MacFarlane,et al.  The NJOY Nu-clear Data Processing System Version 91 , 1994 .

[4]  Hany Samy Abdel-Khalik Adaptive core simulation , 2004 .

[5]  Tomohiro Endo,et al.  Uncertainty estimation of core safety parameters using cross-correlations of covariance matrix , 2013 .

[6]  Matthew Anderson Jessee,et al.  Cross-Section Adjustment Techniques for BWR Adaptive Simulation , 2008 .

[7]  Andreas Pautz,et al.  Influence of nuclear data uncertainties on reactor core calculations , 2011 .

[8]  A. Pautz,et al.  Effects of Nuclear Data Uncertainties on the NEA/OECD PWR MOX/UO2 Core Rod Ejection Benchmark , 2013 .

[9]  K. Shibata,et al.  JENDL-4.0: A New Library for Nuclear Science and Engineering , 2011 .

[10]  Kostadin Ivanov,et al.  BENCHMARK FOR UNCERTAINTY ANALYSIS IN MODELING (UAM) FOR DESIGN, OPERATION AND SAFETY ANALYSIS OF LWRs , 2007 .

[11]  G. L. Holloway,et al.  Core design and operating data for Cycle 3 of Peach Bottom 2. Final report , 1981 .

[12]  Tomohiro Endo,et al.  Application of the Robust Design Concept for Fuel Loading Pattern , 2011 .

[13]  Michael D. McKay,et al.  Evaluating Prediction Uncertainty , 1995 .

[14]  William A. Wieselquist,et al.  Nuclear data uncertainty propagation in a lattice physics code using stochastic sampling , 2012 .