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Thermal Hydraulics
The division provides a forum for focused technical dialogue on thermal hydraulic technology in the nuclear industry. Specifically, this will include heat transfer and fluid mechanics involved in the utilization of nuclear energy. It is intended to attract the highest quality of theoretical and experimental work to ANS, including research on basic phenomena and application to nuclear system design.
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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.”
Felix C. Difilippo, Stephen E. Fisher
Nuclear Technology | Volume 133 | Number 3 | March 2001 | Pages 310-324
Technical Paper | Fuel Cycle and Management | doi.org/10.13182/NT01-A3176
Articles are hosted by Taylor and Francis Online.
Important decisions related to the kind of reactors to be used for the disposition of the surplus weapons-grade plutonium are going to be based on calculations. Benchmarking computational methods in all aspects of the fuel cycle with measured data is then an obvious necessity. Analysis of public domain data reveals that the cycle-2 irradiation in the Quad Cities-1 boiling water reactor is the most recent U.S. destructive examination, involving the irradiation of five mixed-oxide (MOX) assemblies using 80 and 90% fissile Pu, quite close to weapons-grade Pu isotopic. Such measurements are rare, and they might be the only source of information to quantify differences in key neutronics parameters between high-fissile Pu systems and the well-characterized use of reactor-grade Pu. The pin neutronic performances for the UO2 and MOX fuels are compared with assembly-level calculation in which ~20% of the pins are MOX pins surrounded by UO2 pins. For MOX rods, HELIOS models the chains for the isotopes of uranium and plutonium reasonably well when compared with measured data at ~12 000 MWd/tonne. However, indications are that the amounts of heavier actinides are underpredicted. Measurements and calculations of the relative pin power distribution for the last few weeks of the irradiation and the burnup are fairly consistent. The critical effects of the contribution of the 0.296-eV resonance to the production of higher actinides and the destruction of 239Pu are discussed.