A comprehensive survey of inverse uncertainty quantification of physical model parameters in nuclear system thermal–hydraulics codes

Uncertainty Quantification (UQ) is an essential step in computational model validation because assessment of the accuracy requires a concrete, quantifiable measure uncertainty predictions. The concept UQ nuclear community generally means forward (FUQ), which information flow from inputs to outputs. Inverse (IUQ), outputs and experimental data inputs, equally important component but has been significantly underrated until recently. FUQ knowledge input uncertainties specified by expert opinion or user self-evaluation. IUQ defined as process inversely quantify based on data. This review paper aims provide comprehensive comparative discussion major aspects methodologies that have used physical models system thermal-hydraulics codes. methods can be categorized three main groups: frequentist (deterministic), Bayesian (probabilistic), empirical (design-of-experiments). We eight metrics evaluate method, including solidity, complexity, accessibility, independence, flexibility, comprehensiveness, transparency, tractability. Twelve are reviewed, compared, evaluated these metrics. Such evaluation will good guidance for users select proper method problem under investigation.