Evaluation of Neutron Resonance Data and Analysis Techniques for CANDU Type Fuel Bundles

Abstract

We describe the evaluation of the magnitude of the differences when an approximate method is used for the treatment of resonance data -like WIMS method- and when different basic resonance cross-section data are used, for CANDU-Embalse type fuel rod bundles and core neutron calculations. The main conclusions are: the approximate resonance treatment in the WIMS-D/4 code over estimates the resonance absorption more for the interior fuel rods than for the exterior fuel rods in the bundle and under estimates the core reactivity by about 3%. Differences between the basic 238U data for the uncorrected and corrected values in the WIMS library compensated for the 3% difference.