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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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ANS joins others in seeking to discuss SNF/HLW impasse
The American Nuclear Society joined seven other organizations to send a letter to Energy Secretary Christopher Wright on July 8, asking to meet with him to discuss “the restoration of a highly functioning program to meet DOE’s legal responsibility to manage and dispose of the nation’s commercial and legacy defense spent nuclear fuel (SNF) and high-level radioactive waste (HLW).”
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.