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Young Members Group
The Young Members Group works to encourage and enable all young professional members to be actively involved in the efforts and endeavors of the Society at all levels (Professional Divisions, ANS Governance, Local Sections, etc.) as they transition from the role of a student to the role of a professional. It sponsors non-technical workshops and meetings that provide professional development and networking opportunities for young professionals, collaborates with other Divisions and Groups in developing technical and non-technical content for topical and national meetings, encourages its members to participate in the activities of the Groups and Divisions that are closely related to their professional interests as well as in their local sections, introduces young members to the rules and governance structure of the Society, and nominates young professionals for awards and leadership opportunities available to members.
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.”
Xiaotian Li, Xiaowei Li, Li Shi, Zhengming Zhang, Shuyan He
Nuclear Technology | Volume 174 | Number 1 | April 2011 | Pages 29-40
Technical Paper | One-Phase Fluid Flow | doi.org/10.13182/NT11-A11677
Articles are hosted by Taylor and Francis Online.
The hot gas duct vessel (HGDV) is an important part of the high-temperature reactor-pebble-bed module (HTR-PM) primary loop pressure boundary system. It connects the reactor pressure vessel (RPV) and steam generator pressure vessel. Because the dimensions of the HGDV are smaller than those of the other two vessels, it is often considered the weakest of the three vessels. Therefore, the safety of the HGDV has become one of the most important issues in the design of the HTR-PM. In the present paper, a comprehensive safety analysis of the HGDV in the HTR-PM was performed with an emphasis on the structural features. The designs of the HGDV and the support system of the primary loop pressure boundary are first described. A preliminary safety analysis of the HGDV, including the stress calculations and leak-before-break (LBB) analysis, is then presented. The results show that the stress levels of the HGDV under various accidents have a safety margin of at least 55.3% compared with the stress limits specified in American Society of Mechanical Engineers code, and the stress intensity factor at the postulated flaw is less than the critical stress intensity factor. The LBB analysis indicated that the leak detection system is capable of detecting leaks caused by a postulated through-thickness crack in the HGDV before it reaches the critical size. Although the preliminary analysis has proved the safety of the HGDV, the consequences of a hypothetical HGDV double-ended break accident were also studied to further investigate the safety features of the HTR-PM. Several mitigation measures were employed based on the original design. The structural integrity of the support system, the reactor internals, and the containment under double-ended break accident were evaluated. The results show that these main structures could maintain integrity under the HGDV double-ended break accident.