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International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
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Argonne’s METL gears up to test more sodium fast reactor components
Argonne National Laboratory has successfully swapped out an aging cold trap in the sodium test loop called METL (Mechanisms Engineering Test Loop), the Department of Energy announced April 23. The upgrade is the first of its kind in the United States in more than 30 years, according to the DOE, and will help test components and operations for the sodium-cooled fast reactors being developed now.
Jeffrey W. Lane, L. E. Hochreiter, D. L. Aumiller, Jr., R. J. Kushner
Nuclear Technology | Volume 161 | Number 3 | March 2008 | Pages 277-285
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT08-A3926
Articles are hosted by Taylor and Francis Online.
RELAP5-3D currently calculates two-phase pump degradation using the Aerojet Nuclear Corporation (ANC) model. This is an empirical model that relates two-phase pump performance to single-phase pump performance using a set of two-phase degradation multipliers, which are only a function of void fraction. The purpose of the present work was to assess the two-phase pump degradation model in RELAP5-3D and various sets of user-supplied two-phase degradation multipliers by modeling a full-scale, two-phase pump test facility and comparing the simulated results to experimental data. Tests conducted by Ontario Hydro Technologies (OHT) using a full-size CANDU reactor primary heat transport pump were used for this assessment. Presently, this work represents the only RELAP5-3D analysis of these tests that has been performed.The experimental data from the OHT tests and results of this assessment both indicate that there is a pressure effect, in addition to void fraction, that cannot be neglected by safety analysis codes when predicting two-phase pump performance. The RELAP5-3D results showed that the widely used Semiscale two-phase head degradation multipliers did a poor job of predicting the experimental data and utilizing pressure-specific two-phase head degradation multipliers developed by OHT significantly improved code-to-data agreement. These results identify both the inaccuracies of using the Semiscale two-phase degradation multipliers and a weakness in the present formulation of the ANC model. As a result of this work, the Idaho National Laboratory recognized the need to include a pressure dependence in the RELAP5-3D calculation of two-phase pump performance, and this capability will be available in the next release of the code.