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Fusion Energy
This division promotes the development and timely introduction of fusion energy as a sustainable energy source with favorable economic, environmental, and safety attributes. The division cooperates with other organizations on common issues of multidisciplinary fusion science and technology, conducts professional meetings, and disseminates technical information in support of these goals. Members focus on the assessment and resolution of critical developmental issues for practical fusion energy applications.
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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.”
Yonghee Kim, Won Seok Park, Tae Yung Song, Chang Kue Park
Nuclear Science and Engineering | Volume 143 | Number 2 | February 2003 | Pages 141-157
Technical Paper | doi.org/10.13182/NSE03-A2325
Articles are hosted by Taylor and Francis Online.
The height-to-diameter (H/D) ratio of a lead-bismuth eutectic (LBE)-cooled accelerator-driven system (ADS) has been evaluated in terms of the neutron multiplication, the coolant void worth, and the coolant velocity. For a model ADS, an optimization of the H/D ratio is performed with a Monte Carlo code both for the effective multiplication factor keff and for the multiplication of the external neutrons. In the optimization, ten cases of H/D values have been analyzed for a homogeneous fuel blanket. Also, the dependency of the optimal H/D ratio on the target/buffer is addressed. The Monte Carlo simulations show that the optimal H/D configuration of the ADS core is quite different for the two important measures, and a high H/D ratio can provide a significantly higher source multiplication than the traditional pancake core. Furthermore, various core analyses including depletion calculations are conducted for three selected heterogeneous cores with different H/D ratios, which are a small H/D value (pancake type), a medium H/D value, and a high H/D value, respectively. Void reactivity coefficients of the LBE coolant are evaluated and compared for the three designs to quantify the effects of the H/D ratio. Additionally, a thermal-hydraulic analysis has been performed to derive a maximum allowable core height subject to the LBE velocity limit due to its corrosion and erosion characteristics. It is shown that the practically optimal H/D ratio for source multiplication is tightly constrained by the maximum allowable LBE velocity, depending on the core design parameters.