Verification and benchmarking of Peregrine against Halden fuel rod data and Falcon

The Peregrine fuel performance code is under development by the Consortium for Advanced Simulation of LWRs (CASL) program to provide a 3-D D modeling capability for predicting the impact of plant operation and fuel rod design on performance, including Pellet-Cladding Interaction (PCI) failures in current PWRs. The multi-physics and multi-dimensional nature of nuclear fuel performance, and the PCI failure mechanism, makes it a challenging choice as a focus for advanced modeling and simulation. PCI is controlled by the complex interplay of thermal, mechanical, and chemical behavior of a fuel rod during plant operation; thus modeling PCI requires an integral fuel performance code to simulate the intricacies of fuel behavior. This paper presents results documenting the initial verification and validation of a 2-D, axi-symmetric version of Peregrine through benchmarking comparisons to Falcon model predictions and Halden Instrumented Fuel Assembly (IFA) experiments of both thermal and mechanical behavior. Initial benchmark comparisons indicate that Peregrine predictions agree quite well with 2-D Falcon predictions and Halden experimental data on fuel centerline temperature but that further developments are necessary for some models, including fission gas release and gaseous swelling. The mechanical behavior benchmarking study has compared predictions of clad deformation to dilatational measurements in IFA-585.4 and cladding elongation data from IFA-562.1, and the results show promising agreement. Following an overview of the verification and benchmarking activities, the paper will discuss Peregrine predictions to evaluate the effects of PCI by means of comparing to experiments performed in the third RISØ Fission Gas Release project and the Super-Ramp project.