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Division Spotlight
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.
Meeting Spotlight
ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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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.”
Luka Snoj, Ivan Kodeli, Igor Remec
Nuclear Science and Engineering | Volume 178 | Number 4 | December 2014 | Pages 496-508
Technical Paper | doi.org/10.13182/NSE14-30
Articles are hosted by Taylor and Francis Online.
A complete evaluation of the experimental uncertainties of the KRITZ-2 series of critical and relative fission rate experiments was performed within the International Reactor Physics Experiment Evaluation Project. The uncertainties in the benchmark model keff are mainly due to uranium enrichment, plutonium content [mixed oxide (MOX) fuel], pitch, and boron isotopic composition. The largest contribution to the uncertainty in the benchmark model keff is from the uncertainty in the bias due to the homogenization of the particulate MOX fuel. In addition, uncertainties due to nuclear data libraries are presented. The keff's calculated with various nuclear data libraries systematically underpredict the benchmark model keff by one to three times the standard experimental uncertainties. When taking into account uncertainties in nuclear data estimated using SCALE-6.0 and JENDL-4.0m covariances, the benchmark and calculated keff's agree within 1σ of the total—experimental plus calculational—uncertainties. In contrast to the criticality benchmark data, the calculated relative fission rates agree very well with the experimental ones, especially when eliminating systematic errors due to normalization.
