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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.”
Marco Riva, Alice Ying, Mohamed Abdou, Mu-Young Ahn, Seungyon Cho
Fusion Science and Technology | Volume 75 | Number 8 | November 2019 | Pages 1037-1045
Technical Paper | doi.org/10.1080/15361055.2019.1643691
Articles are hosted by Taylor and Francis Online.
In this paper, dynamic tritium flow rates and inventories of the outer fuel cycle (OFC) of a DEMOnstration nuclear fusion reactor (DEMO) are analyzed to determine the initial amount of tritium that has to be prepared to sustain plasma operation at reactor start-up, i.e., until tritium bred in blankets is extracted and available. The main components of the helium coolant ceramic reflector tritium breeding system were modeled in detail with the use of COMSOL Multiphysics and integrated into a system-level model within the MATLAB/Simulink platform to simulate OFC tritium streams. Furthermore, a control volume analysis was derived to incorporate the OFC flow rates calculated with the dynamic integrated numerical tool for initial start-up tritium inventory (ISTI) analysis. We found that the tritium processing time of the tritium extraction system (TES) plays a critical role for ISTI assessment. On one hand, for batchwise technology such as adsorption/regeneration columns, the OFC-attributed ISTI is ~2.6 kg calculated for a 3-GW fusion power reactor. On the other hand, online extraction techniques such as catalytic membrane reactors offer continuous operation and result in ~10 to 250 g of ISTI depending on the TES efficiency and breeder material tritium residence time. The helium coolant system (HCS) line has a minor impact on ISTI since tritium retention in HCS components is orders of magnitude lower than the TES line when a tungsten plasma-facing-component coating is implemented.