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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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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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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New laws offer nuclear industry incentives for existing power plant uprates
This year, the U.S. nuclear industry received a much-needed economic boost that could help preserve operating nuclear power plants and incentivize upgrades that extend their lifespan and power output.
Signed into law in 2022, the Inflation Reduction Act offers production tax credits (PTCs) for existing nuclear power plants and either PTCs or investment tax credits (ITCs) for new carbon-free generation. These credits could make power uprates—increasing the maximum power level at which a commercial plant may operate—a much more appealing option for utilities.
M. W. Golay, K. B. Cady
Nuclear Science and Engineering | Volume 43 | Number 3 | March 1971 | Pages 303-314
Technical Paper | doi.org/10.13182/NSE71-A19976
Articles are hosted by Taylor and Francis Online.
Axial neutron-pulse propagation experiments were conducted in cylindrical cores of the Cornell University Zero Power Reactor (ZPR). Energy-dependent neutron diffusion theory is found to provide a good prediction of the kinetic behavior of the assemblies. At short times the reactor response is that of an infinitely long reactor, and at long times exponential decay of Helmholtz spatial modes is observed. A space-independent pulse propagation velocity is not observed in most of the assemblies. Such a result is obtained only in infinitely long assemblies, and in most finite-length cores end-effect contamination cannot be neglected. In the Laplace transform domain the neutron density wave dispersion relations are obtained when the transform variable ξ is imaginary in the cores which would be prompt-subcritical if they were infinitely long. When ξ is real, the inverse attenuation length which would be measured in a static exponential experiment in an assembly uniformly poisoned by an absorber of strength ξ/υ is obtained. The agreement between the measured parameters and the predictions of diffusion theory improves as the neutron multiplication of the assembly decreases due to decreased end-effect contamination of the infinitely long assembly response. The effective multiplication of an assembly is seen to decrease due to spectral hardening as