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The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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.”
Wen-Shan Lin, Bau-Shei Pei, Chien-Hsiung Lee, I. A. Mudawwar
Nuclear Technology | Volume 85 | Number 2 | May 1989 | Pages 213-226
Technical Paper | Heat Transfer and Fluid Flow | doi.org/10.13182/NT89-A34242
Articles are hosted by Taylor and Francis Online.
A theoretical critical heat flux (CHF) model based on microlayer dryout and Helmholtz instability for subcooled tube flow under pressurized water reactor operation conditions is first extended to the conditions of saturated low-quality flow. Then the applicability of this extended theoretical CHF model to rod bundles is evaluated. The effects of grid spacers, cold wall, and axial heat flux nonuniformity on bundle CHFs are investigated. The extended CHF model is very accurate when compared with three other well-known CHF correlations on a data base of round tube CHF. In the simple case with uniform axial heat flux distribution, simple grid spacers, and no guide tubes in bundles, the theoretical CHF model gives good results. In other more complex cases, the cold-wall effects due to the existence of guide tubes, the effects of mixing vane grids, and the effects of nonuniform axial heat flux distributions on CHF are significant. The present model generally gives satisfactory results when compared with ∼1400 bundle CHF experimental data points although corrections for grid spacers, cold wall, and axial heat flux have not yet been considered.