Towards Implementing Direct Sensitivity and Uncertainty Methods in Thermalhydraulic Codes

Abstract

Proper sensitivity and uncertainty analysis of thermalhydraulic codes is important due to the move from deterministic towards probabilistic strategies. Sensitivity analysis is generally performed using statistical methods for a limited number of important parameters treating the code as a black box simulation. Another option is a direct analytical approach through the use of partial derivatives. Analytical methods, though complex to employ, must only be done once and provide a wealth of sensitivity information that is relevant to any scenario modeled by the simulation. A possible process for applying direct analytical sensitivity analysis to a complex thermalhydraulics code is described herein.