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The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
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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.”
Jacob A. Farber, Daniel G. Cole (Univ of Pittsburgh)
Proceedings | Nuclear Plant Instrumentation, Control, and Human-Machine Interface Technolgies (NPIC&HMIT 2019) | Orlando, FL, February 9-14, 2019 | Pages 868-878
In the nuclear power industry, one important class of accidents is the loss of coolant accident (LOCA). This paper presents methods to detect a LOCA that is initiated: (i) while the plant is going through a small transient, and (ii) with a time-varying leak magnitude. The accident is simulated using a generic pressurized water reactor (GPWR) simulator. The fault is detected using a model-based approach with models identi ed using GPWR data. The model-based approach is multiple-model adaptive estimation (MMAE), which uses multiple system models representing both normal and faulted operating conditions. During operation, these models simulate the potential operating conditions, incorporating measurement feedback in a Kalman lter state-estimation structure. Faults are detected by selecting the model that most closely matches the system according to statistical characteristics. For a LOCA, data-driven models of the pressurizer liquid level are derived using rst-principles and system identi cation. In system identi cation, a physics-based model form is derived that contains unknown parameters. System identi cation is then used to estimate the parameter values based on measurement data, providing plant-speci c pressurizer models. For the accident scenario described above, the proposed methods di erentiate between the transient and the accident, and provide real-time estimates of the leak magnitude after it has been initiated.