Capabilities of the FALCON Steady State and Transient Fuel Performance Code

Abstract

The recent advent of several key behavioral issues in nuclear fuel performance, resulting from the trend toward increased fuel utilization, has created the need for enhanced steady state and transient fuel rod analysis capabilities. These issues, derived primarily from burnup-induced pellet changes and increased hydrogen uptake (as a byproduct of corrosion) occurring at higher burnups, impact steady state operation and licensing issues such as postulated reactivity initiated accidents (RIA), loss-of-coolant accidents (LOCA), and spent fuel storage and transportation. In response, EPRI has undertaken the development of FALCON, an integrated steady state and transient fuel performance analysis code applicable to the full range of fuel operating regimes. The FALCON development program has emphasized the use of advanced thermo-mechanics in a fully two-dimensional finite element continuum framework. Based on the architecture of the FREY transient analysis code and including salient models from the ESCORE steady state analysis code, FALCON provides enhanced steady state and transient numerics, updated material property and behavioral models, and an expanded and relevant light water reactor (LWR) benchmarking and verification database. This paper will present an overview of the FALCON steady state analysis development program with an emphasis on the results from the benchmarking, verification, and validation activities.