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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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World Bank, IAEA partner to fund nuclear energy
The World Bank and the International Atomic Energy Agency signed an agreement last week to cooperate on the construction and financing of advanced nuclear projects in developing countries, marking the first partnership since the bank ended its ban on funding for nuclear energy projects.
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.