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Division Spotlight
Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
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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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Latest News
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.
Keisho Shirakata, Toshio Sanda, Fumiaki Nakashima
Nuclear Science and Engineering | Volume 131 | Number 2 | February 1999 | Pages 187-198
Technical Paper | doi.org/10.13182/NSE99-A2027
Articles are hosted by Taylor and Francis Online.
Space-dependent nuclear characteristics, measured by critical experiments on large-size fast breeder reactor (FBR) cores, were reviewed and interpreted. It was observed that radial neutron flux distributions were significantly distorted by perturbations, control rod reactivity interaction effects were large, and the point kinetics was not valid. These physical behaviors are enhanced as the spatial neutronic decoupling increases. To obtain stable and benign nuclear characteristics and to make the kinetics as close to the point kinetics as possible, it is necessary to reduce the spatial decoupling. This is an important issue that must be taken into account in the nuclear design for large FBR cores.A new nuclear core design method for large FBR cores is proposed in which neutronic stability is considered at the same time as performance and safety for the optimization of core design. The neutronic stability is improved by reducing the spatial decoupling and by taking into account the spatial higher harmonics.