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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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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.”
T. C. Chawla
Nuclear Science and Engineering | Volume 48 | Number 4 | August 1972 | Pages 397-402
Technical Paper | doi.org/10.13182/NSE72-A22507
Articles are hosted by Taylor and Francis Online.
Through the use of potential flow theory, an expression for two-dimensional axisymmetric pressure distribution in an “infinite” plenum for a coolant-expulsion process in a single-subassembly accident is obtained. An expression for the temporal distribution of the corresponding spatially averaged pressure at the exit of a fuel subassembly is also obtained. The illustrative example considered indicates that the use of a fixed-pressure boundary condition instead of a time-dependent-pressure boundary condition at the exit (or at the inlet) of a subassembly is not valid for very rapid transients, such as due to molten fuel-coolant interaction or to rapid release of fission gas from simultaneous or near-simultaneous breach of several pins near the top of the core region. Furthermore, the results of sample calculations presented for an FFTF subassembly indicate the possibility that, for a sufficiently rapid transient, the transient pressure in the exit region of the subassembly can fall to the saturation pressure of the sodium and result in local boiling during the expulsion in the exit region of the subassembly. The expression developed here for the transient, spatially averaged pressure distribution in the plenum at the exit of a subassembly could be coupled with the one-dimensional type of analysis of the expulsion process in the fuel subassembly.