Sensitivity and Uncertainty Analysis of Debris Bed Coolability

Abstract

Theoretical studies of top-fed debris bed coolability available so far have been focused on obtaining the Dryout Heat Flux (DHF) as a function of debris bed parameters (mean particle diameter and porosity). In this paper, uncertainty analysis is carried out to quantify the influence of different factors on DHF. Global sensitivity analysis is applied to rank the drag model parameters according to their effects on DHF and average pressure drop (epistemic uncertainty). The most influential model parameters are then optimized to achieve the best fit to experimental data available. Finally, aleatory Uncertainties due to randomness of the debris bed formation scenario and respective physical parameters (particle diameter, porosity) are quantified.