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The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
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ANS Student Conference 2025
April 3–5, 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.”
Jin Ho Song
Nuclear Technology | Volume 170 | Number 1 | April 2010 | Pages 114-122
Technical Paper | Special Issue on the 2008 International Congress on Advances in Nuclear Power Plants / Thermal Hydraulics | doi.org/10.13182/NT10-A9450
Articles are hosted by Taylor and Francis Online.
An optimal geometrical configuration that results in a maximum loop flow rate at given volume constraints is investigated for a two-phase natural circulation loop and a single-phase natural circulation loop. A rectangular loop connected with pipes is considered, which consists of a heater, a cooler, a riser, and a downcomer. By varying the aspect ratio of the loop, the number of pipes in the heating and cooling sections, and the distribution of the volumes between the cold side and the hot side, an optimal loop configuration that results in a maximum loop flow rate is determined from an analytical solution using simplifying assumptions. It is shown that the optimal configuration is beneficial in terms of minimizing the temperature rise and the pressure rise at given heat input. To support the argument, a complementary numerical analysis for a two-phase natural circulation flow in a rectangular loop is performed. The results are in good agreement with those predicted by the analytical models.