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Aerospace Nuclear Science & Technology
Organized to promote the advancement of knowledge in the use of nuclear science and technologies in the aerospace application. Specialized nuclear-based technologies and applications are needed to advance the state-of-the-art in aerospace design, engineering and operations to explore planetary bodies in our solar system and beyond, plus enhance the safety of air travel, especially high speed air travel. Areas of interest will include but are not limited to the creation of nuclear-based power and propulsion systems, multifunctional materials to protect humans and electronic components from atmospheric, space, and nuclear power system radiation, human factor strategies for the safety and reliable operation of nuclear power and propulsion plants by non-specialized personnel and more.
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Utility Working Conference and Vendor Technology Expo (UWC 2024)
August 4–7, 2024
Marco Island, FL|JW Marriott Marco Island
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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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BWXT will scout potential TRISO fuel production sites in Wyoming
BWX Technologies Inc. announced today that its Advanced Technologies subsidiary has signed a cooperation agreement with the state of Wyoming to evaluate locations and requirements for siting a potential new TRISO nuclear fuel fabrication facility in the state.
W. R. Waltz, J. F. Walter
Nuclear Technology | Volume 10 | Number 2 | February 1971 | Pages 160-167
Technical Paper and Note | Reactor | doi.org/10.13182/NT71-A30923
Articles are hosted by Taylor and Francis Online.
Comparisons of calculation and experiment have been performed to test the adequacy of fewgroup subcritical diffusion theory in predicting neutron detector response induced from material changes in a subcritical water-moderated reactor. In many operations involving material changes in a subcritical reactor, it is desired to monitor changes in the multiplication factor (Keff) of the system to ensure the safety of an operation by avoiding an accidental close approach to criticality. This monitoring procedure is accomplished by the introduction of artificial neutron sources to the system and by the proper interpretation of changes in neutron detector readings in terms of Keff. Because of the rather complicated involvement of the source-core-detector system, proper interpretation of detector response observed during these operations can only be achieved by the availability to predict detector response obtained from an accurate calculational model. Comparisons of calculation to experiment show that diffusion theory may be used successfully for these purposes; however, certain limitations of the model must be recognized and avoided. The breakdown of the calculational model in certain cases can be related ultimately to the inability of few-group diffusion theory to predict the absolute magnitude of detector flux for large distances through a water (or metal-water) shield. This inability can result in inaccuracies in predicted count rate response when applied to a specific source-core-detector arrangement with the characteristic that a given material change results in gross changes in the axial flux distribution. These effects can be overcome by the suitable positioning of the neutron source and detector relative to the subcritical assembly.
