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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.
G. Breitbach, H. Barthels
Nuclear Technology | Volume 49 | Number 3 | August 1980 | Pages 392-399
Technical Paper | Reactor | doi.org/10.13182/NT80-A17687
Articles are hosted by Taylor and Francis Online.
In the case of hypothetical accidents, temperatures of ∼2000 to 3000°C are expected in the core of a pebble-bed high temperature reactor (HTR). At such high temperatures the transport of heat by radiation is the most important mechanism. For the calculations of temperature pattern in the reactor core, the effective thermal conductivity λeff of the pebble bed must be known. Two models predicting λeff are represented. They are the cell model of Zehner and Schluender and the modified radiation model of Vortmeyer, which has been extended to high temperatures. A transient measurement method was used to determine the effective thermal conductivity of pebble beds of graphite and of zirconium oxide at temperatures up to 1000 and 1500°C, respectively. The theoretical λeff values are compared with experimental results. The theoretical values of λeff predicted by the Zehner-Schluender formula are too low, while the λeff values of the modified radiation model are somewhat too high. Corrections to both formulas were made. Finally, it is demonstrated which values of λeff are predicted by high temperatures in the pebble bed of the HTR.