Comparative Studies of Sensitivity Analysis for Coupled VERA-CS/FRAPCON and VERA-CS/BISON Simulations

摘要

An approach to uncertainty quantification and sensitivity analysis with coupled simulations of VERA-CS/FRAPCON and VERA-CS/BISON was developed within the Multi-Physics Best Estimate Plus Uncertainty (MP-BEPU) safety analysis framework LOTUS. A single assembly model was developed for the VERA-CS simulations and FRAPCON and BISON models were developed for the hot rod in the assembly. Uncertainly quantification and sensitivity analysis were performed with 23 uncertain input parameters for the coupled VERA-CS/FRAPCON simulations and with 31 uncertain input parameters for the coupled VERA-CS/BISON simulations. The maximum fuel centerline temperature (MFCT) and gap conductance at peak power (GCPP) were selected as the figures of merit (FOM). Pearson and Spearman Correlation Coefficients, Sobol Indices and Moment Independent Delta Measures were considered in the sensitivity analysis.