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Accelerator Applications
The division was organized to promote the advancement of knowledge of the use of particle accelerator technologies for nuclear and other applications. It focuses on production of neutrons and other particles, utilization of these particles for scientific or industrial purposes, such as the production or destruction of radionuclides significant to energy, medicine, defense or other endeavors, as well as imaging and diagnostics.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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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General Kenneth Nichols and the Manhattan Project
Nichols
The Oak Ridger has published the latest in a series of articles about General Kenneth D. Nichols, the Manhattan Project, and the 1954 Atomic Energy Act. The series has been produced by Nichols’ grandniece Barbara Rogers Scollin and Oak Ridge (Tenn.) city historian David Ray Smith. Gen. Nichols (1907–2000) was the district engineer for the Manhattan Engineer District during the Manhattan Project.
As Smith and Scollin explain, Nichols “had supervision of the research and development connected with, and the design, construction, and operation of, all plants required to produce plutonium-239 and uranium-235, including the construction of the towns of Oak Ridge, Tennessee, and Richland, Washington. The responsibility of his position was massive as he oversaw a workforce of both military and civilian personnel of approximately 125,000; his Oak Ridge office became the center of the wartime atomic energy’s activities.”
K. N. Schwinkendorf
Nuclear Science and Engineering | Volume 132 | Number 1 | May 1999 | Pages 118-126
Technical Paper | doi.org/10.13182/NSE99-A2053
Articles are hosted by Taylor and Francis Online.
Severe accident simulation has been performed in the past to predict the energy release arising from hypothetical core disruptive accidents (CDA) postulated to occur in liquid-metal reactors (LMRs). This field has developed to a mature state with the creation of computer codes such as SIMMER, but these codes are highly specific to LMR designs. More recent attention has focused on thermal-spectrum criticality accidents. This has resulted in the creation of a new simulator code, A Transient History for Energetic Nuclear Accidents_2D (ATHENA_2D), which solves the transient multigroup space-time kinetics equations, coupled to multichannel thermal hydraulics and computational fluid dynamics. This paper presents results from two-dimensional kinetics simulations performed for a water reflood recriticality accident in a damaged light water reactor, typical of a Three Mile Island end-state core geometry. The accident is initiated by assuming reflood water that is insufficiently borated and a reactivity-optimized debris bed. Reactivity insertion rates analyzed in this study generally are smaller than in LMR CDAs (tens of dollars per second versus up to hundreds of dollars per second), and the energetics are slightly lower. Parametric variation of input was performed, including reactivity insertion rate and initial temperature.
