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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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DOE-NE’s newest fuel consortium includes defense from antitrust laws
The Department of Energy's Office of Nuclear Energy is setting up a nuclear fuel Defense Production Act Consortium that will seek voluntary agreements with interested companies “to increase fuel availability, provide more access to reliable power, and end America’s reliance on foreign sources of enriched uranium and critical materials needed to power the nation’s nuclear renaissance.” According to an August 22 DOE press release, the plan invokes the Defense Production Act (DPA) to give consortium members “defense from antitrust laws when certain criteria are met” and “allow industry consultation to develop plans of action.” DOE-NE is looking for interested companies to join the consortium ahead of its first meeting, scheduled for October 14.
J. D. Rader, M. S. Greenwood, A. M. Melin, A. J. Wysocki (ORNL), G. M. Borza C. D. Lietwiler (SMR Inventec, LLC)
Proceedings | Nuclear Plant Instrumentation, Control, and Human-Machine Interface Technolgies (NPIC&HMIT 2019) | Orlando, FL, February 9-14, 2019 | Pages 765-775
A cooperative research and development agreement between Oak Ridge National Laboratory (ORNL) and Holtec International subsidiary SMR Inventec, LLC, was crafted to explore the primary flow stability of the SMR-160, a natural circulation-based pressurized-water small modular reactor. It is necessary to investigate the stability of the system at operational power levels when natural circulation is the driver of the primary flow to show that operation of the plant is stable, predictable, and controllable. The first phase of the analysis was a code-to-code benchmarking activity between RELAP5-3D and the Modelica-based, ORNL-developed TRANSFORM library. The benchmarking included both generic comparisons of heated channels and step-change transients of certain plant boundary conditions of interest. Following the benchmarking, a parametric series of linear stability tests was performed using discrete signals applied to one of several boundary conditions. These signals excite the natural harmonics of the system and produce small perturbations in the power of the reactor. Though some resonant behavior was observed, the results indicate stable operation of the SMR-160 at the conditions investigated. The frequency range covered included several octaves on either side of the loop transit frequency. Thus, a reasonable determination of the stability and controllability of the plant can be made over a large range of timescales.