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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.
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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.
Emerson Paul Chivington, William E. Kastenberg
Nuclear Science and Engineering | Volume 83 | Number 3 | March 1983 | Pages 350-365
Technical Paper | doi.org/10.13182/NSE83-A17568
Articles are hosted by Taylor and Francis Online.
A technique is developed for the treatment of space-time neutron kinetics, which can include the effects of material motion. The new method is applied to sample problems where azimuthal fuel motion is postulated to occur. The technique developed employs the finite element method, Gear's variable predictor corrector scheme, and a Lagrangian mesh that moves with the reactor materials. We treat a cylindrical reactor in (r,θ) geometry. Because finite elements are used to describe both the fluxes and the boundaries of the mesh elements, the resulting deformed elements could be arbitrarily shaped. Second-order polynomials (elements) were found to be better than linear polynomials in treating the geometry because of the curved boundaries used in the problem. Azimuthal motion was found to increase reactivity, and large motion resulted in large increases in reactor power for the cases studied. However, the cases studied showed that azimuthal motion was less important than both inward and outward radial motion. Point kinetics (based on first-order perturbation theory) did not accurately predict the power excursion in cases where substantial azimuthal displacement occurred.