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Division Spotlight
Robotics & Remote Systems
The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
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
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.
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.