PARET-ANL Modeling of a SPERT-IV Experiment Under Different Departure from Nucleate Boiling Correlations

This study presents numerical modeling of the SPERT-IV D-12/25 tests, a series of reactivity insertion, self-limiting, transients for a variety of coolant flow conditions. The PARET-ANL code is used to simulate the system response under these reactivity-initiated accident conditions and estimate the measured damage-indicating parameters - including the cladding temperature - using three departure from nucleate boiling (DNB) correlations, namely, those of Tong, Mirshak, and Bernath. The main objective of this sensitivity analysis is to identify, through performance measures, the DNB correlation influence on the prediction of the transient behavior. It appears that for reactivity insertions >1.20 $, the predicted transient behavior varies significantly depending on the applied DNB correlation. In addition, this study discusses the degree of conservatism introduced by each DNB correlation in the peak clad temperature estimates.