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Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
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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.”
Klaus-Peter Kröhn (GRS)
Proceedings | 16th International High-Level Radioactive Waste Management Conference (IHLRWM 2017) | Charlotte, NC, April 9-13, 2017 | Pages 299-306
Inflow scenarios for a deep geological repository imply that two distinct phases, a gaseous and a liquid phase, can be found in the pore space. The wetting dynamics depend strongly on two constitutive relations (CR): the capillary pressure-saturation relation (CPS) and the relative permeability-saturation relation. Knowledge of these CRs is thus a prerequisite for modelling flow into borehole or drift backfill during the post-operational phase.
In a repository in rock salt the lithostatic load leads to drift and borehole convergence. Backfill consisting of crushed salt is subject to compaction and concurrent decrease of the pore space which has in turn a strong impact on the CRs for two-phase flow. Presented here are first results of still ongoing tests on CRs for potential backfill material, envisaged for a German repository, at different compaction levels.
The CPS-curves derived so far show similar characteristics as the curves for common soils along with the expected increase at decreasing porosity. The relative gas permeability, however, cannot be fitted to classic approaches like the well-known equations of Brooks and Corey. The hydraulic behaviour of the material is thus not yet understood deeply enough to allow reliable model predictions and requires further investigations.