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Division Spotlight
Materials Science & Technology
The objectives of MSTD are: promote the advancement of materials science in Nuclear Science Technology; support the multidisciplines which constitute it; encourage research by providing a forum for the presentation, exchange, and documentation of relevant information; promote the interaction and communication among its members; and recognize and reward its members for significant contributions to the field of materials science in nuclear technology.
Meeting Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
Standards Program
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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Report: New York state adding 1 GW of nuclear to fleet
New York Gov. Kathy Hochul has instructed the state’s public electric utility to add at least 1 gigawatt of new nuclear by building a large-scale nuclear plant or a collection of smaller modular reactors, according to the Wall Street Journal.
H. J. Uitslag-Doolaard, F. Alcaro, F. Roelofs, K. Zwijsen (NRG)
Proceedings | 2018 International Congress on Advances in Nuclear Power Plants (ICAPP 2018) | Charlotte, NC, April 8-11, 2018 | Pages 945-954
The description of the “Dissymmetric Test” performed in the Phénix sodium fast reactor has recently become available as a blind benchmark for thermal-hydraulic modelling within the H2020 SESAME project. The transient consists of a largely asymmetric temperature distribution in the sodium pool resulting from a pump trip in one of the two intermediate circuits, followed by a reactor scram. Although this transient is particularly suitable to validate a 3-D Computational Fluid Dynamics (CFD) model of the thermal-hydraulics in the sodium pool, the computational cost of a relatively long transient analysis with a full-scope CFD model of the whole Phénix reactor system would be huge. The present paper describes the system thermal-hydraulic (STH) model and the multiscale approach adopted by NRG for the simulation of the Dissymmetric Test. The in-house STH code SPECTRA was used to model the complete primary and secondary sides (intermediate loops) and explicitly coupled with the CFD code ANSYS CFX. The latter was used to resolve the details of the flow distribution inside the sodium pools, as well as at the outlet window of the primary side of the intermediate heat exchangers. An STH stand-alone simulation of the transient was carried out for comparison.