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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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Latest News
Leading the charge: INL’s role in advancing HALEU production
Idaho National Laboratory is playing a key role in helping the U.S. Department of Energy meet near-term needs by recovering HALEU from federal inventories, providing critical support to help lay the foundation for a future commercial HALEU supply chain. INL also supports coordination of broader DOE efforts, from material recovery at the Savannah River Site in South Carolina to commercial enrichment initiatives.
Jeffrey W. Lane, David L. Aumiller, Jr., Lawrence E. Hochreiter, Fan-Bill Cheung
Nuclear Technology | Volume 177 | Number 2 | February 2012 | Pages 176-187
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT12-A13364
Articles are hosted by Taylor and Francis Online.
A three-field countercurrent flow limitation (CCFL) model based on the classic flooding curve methodology has been developed and successfully demonstrated in a derivative of the COBRA-TF code. The various physical mechanisms (wave reversal, liquid bridging, and wave interfacial instability) supposed to govern the flooding and flow reversal phenomena are extremely complex and geometric dependent. As a result universally applicable numerical models for these phenomena are not currently available. The chosen approach provides flexibility and leverages the available experimental data to improve the predictive capability of the code. The model is an extension of the standard two-field (liquid-vapor) CCFL model to a three-field (liquid films, vapor, and liquid droplets) CCFL model. This extension includes providing the appropriate set of momentum equations, definitions of required superficial velocities, and new entrainment rate correlations based on CCFL conditions. Necessary criteria to enter and exit the model in a numerically stable manner are also described. The implementation of the model was verified and was shown to provide increased numerical stability in the code predictions. Improvement in the code-to-data agreement of the allowable downward liquid penetration rate for the Dukler and Smith experiments is also demonstrated.