Abstract
The Tiamat code is being developed by CASL (Consortium for Advanced Simulation of Light
Water Reactors) as an integrated tool for predicting pellet-clad interaction and improving the high-fidelity core simulator. Tiamat integrates the advanced core simulator capabilities of CASL, VERA-CS, with the multi-dimensional Bison-CASL fuel performance code. VERA-CS provides the coupling of the COBRA-TF sub-channel thermal hydraulics and fuel heat transfer capability with either the Insilico or MPACT neutronics solvers. This report discusses the two neutronics components of VERA and provides a parametric study of the performance of Tiamat using both neutronics codes and a comparison with the VERA-CS version of both. It is demonstrated that Tiamat is robustly capable of modeling pellet-clad interaction and highlights some differences in results due to inclusion of a rigorous fuel performance model rather than simple rod heat transfer.
