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Reactor Physics
The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
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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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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.
Erik L. Vold, Anil K. Prinja, Farrokh Najmabadi, Robert W. Conn
Fusion Science and Technology | Volume 22 | Number 2 | September 1992 | Pages 208-226
Technical Paper | Plasma Engineering | doi.org/10.13182/FST92-A30104
Articles are hosted by Taylor and Francis Online.
A one-group diffusion approximation to neutral transport in a plasma is incorporated in a two-dimensional (θ-r) computational code, EPIC, coupling transport and recycling of the plasma-neutral fluids in a consistent finite discretization scheme. Boundary conditions accommodate particle recycling at the edge-core plasma interface. Neutral particle reflection from the pumping duct characterizes a given pumping system. Marginal validity of the diffusion approximation motivates extensive comparisons of the results with Monte Carlo (DEGAS) transport calculations. In prescribed and in self-consistently computed plasma solutions, the neutral diffusion results are comparable with the Monte Carlo results for radial and poloidal profiles of atomic neutral density over a wide range of limiter and divertor edge plasmas. Steady-state density and temperature contours for the Axially Symmetric Divertor Experiment (ASDEX) diverted tokamak are consistent with previous computations using fixed boundary conditions at the separatrix, but show reduced (20%) recycling attributed to the more realistic neutral atom transport by charge-exchange scattering in the diffusion model. Time-dependent plasma solutions with flux boundary conditions across the separatrix are more consistent with experimental data than results with fixed value boundary conditions at the separatrix. The flux across the separatrix is dominated by recycled particles from the edge plasma. A conclusion is that while the one-group diffusion treatment oversimplifies the physics of neutral transport, it is computationally efficient and adequate in accuracy and therefore well suited for edge plasma and for plasma-neutral recycling studies.