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Division Spotlight
Education, Training & Workforce Development
The Education, Training & Workforce Development Division provides communication among the academic, industrial, and governmental communities through the exchange of views and information on matters related to education, training and workforce development in nuclear and radiological science, engineering, and technology. Industry leaders, education and training professionals, and interested students work together through Society-sponsored meetings and publications, to enrich their professional development, to educate the general public, and to advance nuclear and radiological science and engineering.
Meeting Spotlight
2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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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Proving DRACO will deliver
The United States is now closer than it has been in over five decades to launching the first nuclear thermal rocket into space, thanks to DRACO—the Demonstration Rocket for Agile Cislunar Orbit.
Heinz Nabielek, Werner Schenk, Werner Heit, Alfred-Wilhelm Mehner, Daniel T. Goodin
Nuclear Technology | Volume 84 | Number 1 | January 1989 | Pages 62-81
Technical Paper | Nuclear Fuel | doi.org/10.13182/NT89-A34196
Articles are hosted by Taylor and Francis Online.
Coated particles embedded in graphitic elements are the fuel for the High-Temperature Reactor (HTR). Experimental investigations of the performance of particles at extremely high temperatures have been conducted to achieve an understanding of coating failure mechanisms and to establish the data base for safety and risk analyses of hypothetical accidents in large-and medium-sized HTRs. The primary mechanism for coating failure and fission product release in the 1900 to 2500°C temperature range is thermal decomposition of silicon carbide (SiC). Heating tests have provided the activation energy of this process and the correlation of SiC decomposition with coating failure and subsequent fission product release. The process of fission product release proceeds in several stages. A certain amount of SiC removal at high temperatures leads to SiC deterioration, which renders a fraction of particles permeable to cesium and strontium. During 50°C/h ramped heating tests, the cesium release approaches 100% at 2500°C. With the onset of SiC failure, the release process of xenon, krypton, and iodine via diffusion through the pyrocarbon (PyC) is initiated. Under all heating conditions examined, krypton release is significantly delayed relative to cesium release due to the higher diffusivity of cesium in PyC. In the intermediate temperature range of 1600 to 1700°C (the maximum temperature in small, modular HTRs), SiC decomposition rates are negligible, and coated particle fuels retain all safety-relevant fission products.