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Nuclear Nonproliferation Policy
The mission of the Nuclear Nonproliferation Policy Division (NNPD) is to promote the peaceful use of nuclear technology while simultaneously preventing the diversion and misuse of nuclear material and technology through appropriate safeguards and security, and promotion of nuclear nonproliferation policies. To achieve this mission, the objectives of the NNPD are to: Promote policy that discourages the proliferation of nuclear technology and material to inappropriate entities. Provide information to ANS members, the technical community at large, opinion leaders, and decision makers to improve their understanding of nuclear nonproliferation issues. Become a recognized technical resource on nuclear nonproliferation, safeguards, and security issues. Serve as the integration and coordination body for nuclear nonproliferation activities for the ANS. Work cooperatively with other ANS divisions to achieve these objective nonproliferation policies.
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ANS Student Conference 2025
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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.”
Timothy J. Drzewiecki, Brian L. Mount, Martin Lopez de Bertodano
Nuclear Technology | Volume 165 | Number 1 | January 2009 | Pages 18-31
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT09-A4059
Articles are hosted by Taylor and Francis Online.
The fast boron shutdown injection system in the CNA II pressurized heavy water reactor consists of a set of jets flowing through a very large moderator tank that contains an array of cylindrical coolant channels. The prediction of the turbulent jet mixing is required to determine an accurate distribution of boron inside the moderator tank. The boron distribution is used to calculate the multidimensional insertion of negative reactivity into the reactor during fast shutdown in a PARCS/RELAP5 model of CNA II.A computational fluid dynamics (CFD) code is used to determine the distribution of boron in the moderator tank. The flow is analyzed with a porous-medium model based on volume-averaged momentum, turbulent kinetic energy, and turbulence dissipation equations. The additional source terms that arise due to the averaging must be constituted. The constitutive relations for the additional source terms that are implemented in the present model are (a) the drag force on an array of cylinders for the momentum equations and (b) the additional mixing effect of the cylinders, which results in the sources of turbulent kinetic energy and turbulence dissipation transport equations.The CFD analysis is performed on a porous, axisymmetric domain. The CFD results are compared with data for the boron concentration distribution obtained in a scaled geometrically similar experiment, demonstrating the validity of the approach. Finally, based on the similarity of turbulent jets, the validated model is scaled up to prototypic conditions and inserted into the PARCS/RELAP5 model.
