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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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Fusion Science and Technology
Latest News
Taking shape: Fusion energy ecosystems built with public-private partnerships
It’s possible to describe fusion in simple terms: heat and squeeze small atoms to get abundant clean energy. But there’s nothing simple about getting fusion ready for the grid.
Private developers, national lab and university researchers, suppliers, and end users working toward that goal are developing a range of complex technologies to reach fusion temperatures and pressures, confounded by science and technology gaps linked to plasma behavior; materials, diagnostics, and electronics for extreme environments; fuel cycle sustainability; and economics.
Anek Kumar, S. Ganesan
Nuclear Science and Engineering | Volume 172 | Number 1 | September 2012 | Pages 20-32
Technical Paper | doi.org/10.13182/NSE11-16
Articles are hosted by Taylor and Francis Online.
In the WIMSD-IAEA multigroup nuclear data library, the isotopes and weights adopted for WLUP libraries to calculate the average fission spectra for 235U, 238U, and 239Pu are in the ratio of 54%, 8%, and 38%, respectively. The average fission neutron spectrum in the existing multigroup WIMSD-IAEA library applicable for the U-Pu cycle is not rigorously applicable for systems that are based on the thorium fuel cycle because of two aspects. First, the weightage of the fission neutron spectrum of 232Th and 233U nuclides, which are important isotopes in the thorium fuel cycle, are not considered in obtaining the average multigroup fission spectrum in the conventional WIMSD-IAEA library. Second, the 232Th/233U system spectrum is required for condensation of the fission spectrum as done in generating other multigroup cross sections and parameters for the thorium fuel cycle. In this work, we have processed the fission neutron spectrum data from the basic evaluated nuclear data file (ENDF/B-VI.8) for each important isotope in the thorium fuel cycle using the Th/233U spectrum and using a FORTRAN program developed and validated by us for this purpose. The final average fission spectrum to be fed into the WIMSD-IAEA library is prepared by mixing the isotopic multigroup fission spectrum of individual isotopes 233U, 239Pu, and 241Pu with appropriate weights corresponding to their respective power fractions in the advanced heavy water reactor (AHWR) lattice. Using the WIMSD library with modified effective fission spectra, the lattice k-infinity calculations of AHWR are performed as a function of burnup. The difference in the infinite multiplication factor, which is expressed in terms of reactivity in mk, ranges from 0.48 to 0.94 mk as burnup in the AHWR proceeds from 0 to 55 GWd/tonne.