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Division Spotlight
Nuclear Criticality Safety
NCSD provides communication among nuclear criticality safety professionals through the development of standards, the evolution of training methods and materials, the presentation of technical data and procedures, and the creation of specialty publications. In these ways, the division furthers the exchange of technical information on nuclear criticality safety with the ultimate goal of promoting the safe handling of fissionable materials outside reactors.
Meeting Spotlight
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
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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Latest News
TerraPower begins U.K. regulatory approval process
Seattle-based TerraPower signaled its interest this week in building its Natrium small modular reactor in the United Kingdom, the company announced.
TerraPower sent a letter to the U.K.’s Department for Energy Security and Net Zero, formally establishing its intention to enter the U.K. generic design assessment (GDA) process. This is TerraPower’s first step in deployment of its Natrium technology—a 345-MW sodium fast reactor coupled with a molten salt energy storage unit—on the international stage.
F. Behafarid, D. Shaver, I. A. Bolotnov, S. P. Antal, K. E. Jansen, M. Z. Podowski
Nuclear Technology | Volume 181 | Number 1 | January 2013 | Pages 44-55
Technical Paper | Special Issue on the 14th International Topical Meeting on Nuclear Reactor Thermal Hydraulics (NURETH-14) / Reactor Safety; Thermal Hydraulics | doi.org/10.13182/NT13-A15755
Articles are hosted by Taylor and Francis Online.
The objective of this paper is to give an overview of a multiscale modeling approach to three-dimensional (3-D) two-phase transient computer simulations of the injection of a jet of gaseous fission products into a partially blocked sodium fast reactor (SFR) coolant channel following localized cladding overheat and breach. The phenomena governing accident progression have been resolved at two different spatial and temporal scales by the intercommunicating computational multiphase fluid dynamics codes PHASTA (at direct numerical simulation level) and NPHASE-CMFD (at Reynolds-averaged Navier-Stokes level). The issues discussed in the paper include an overview of the proposed 3-D two-phase-flow models of the interrelated phenomena that occur as a result of cladding failure and the subsequent injection of a jet of gaseous fission products into partially blocked SFR coolant channels and gas-molten-sodium transport along the channels. An analysis is presented on the consistency and accuracy of the models used in the simulations, and the results are shown of the predictions of gas discharge and gas-liquid-metal two-phase flow in a multichannel fuel assembly. Also, a discussion is given of the major novel aspects of the overall work.
