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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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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.”
Nathan E. White, Sudarshan K. Loyalka
Nuclear Science and Engineering | Volume 181 | Number 3 | November 2015 | Pages 318-330
Technical Paper | doi.org/10.13182/NSE15-10
Articles are hosted by Taylor and Francis Online.
In high-temperature gas-cooled reactors (HTGRs), carbonaceous dust can be generated both during normal operations and during accidents. The dust particles can be highly irregular and highly porous and have very large surface areas that may make dust-facilitated (or dust-hindered) fission product (FP) transport a major factor. Since the FP interactions with dust can occur while the dust is on a surface as well as in suspension, there is a need to obtain computational and experimental results for both situations. In 2014, Smith and Loyalka used the Green's Function Method to study condensation (results for absorption/deposition and evaporation are generally directly related to the condensation problem) on chainlike particles and particle agglomerates in the diffusion regime. In 2010, Smith and Loyalka made progress in computation of evaporation/condensation particles on a surface, but again in the diffusion regime. Since the particle sizes of interest span a wide range—from nanometers to microns (10−9 m to 10−6 m)—and are also porous with small pores and pathways for FPs, these computations need to be extended to the transport regime where the particle sizes (and/or pores) are comparable to the vapor (FP) molecular mean free path (∼0.05 μm) in the gaseous phase (air or helium, or some mix thereof with other contaminants). The focus of the present paper is on Monte Carlo computation of condensation rate on chainlike particles and particle agglomerates in the transport regime using the one-speed approximation, and we report a number of new results that provide new insights and path for future explorations.