CTF application to BWR modeling and simulations

CTF, the version of COBRA-TF being jointly developed and maintained by Pennsylvania State University and Oak Ridge National Laboratory for applications in the Consortium for Advanced Simulation of Light Water Reactors (CASL), uses a two-fluid, three-field representation of two-phase flow, which makes it capable of modeling the high-void flow expected in BWR operation. This paper focuses on application of CTF to mini- And whole-core BWR calculations on the pin-cell resolved level as well as demonstrating that CTF can properly model bypass flow. To increase the confidence in CTF's BWR modeling capabilities, extensive simulations have been performed using the international Organization for Economic Cooperation and Development (OECD) / US Nuclear Regulatory Commission (NRC) Oskarshamn-2 benchmark, including modeling of a single and 2x2 assemblies on pin by pin level, and a full core model on assembly level. Each model is varied, with an increasing amount of detail. The results demonstrate that CTF is capable of modeling basic and complex BWR simulations. Using the three Oskarshamn-2 simulations, CTF's capabilities of modeling BWRs was further verified.