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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.
Allen Barnett, J. E. Morel, D. R. Harris
Nuclear Science and Engineering | Volume 102 | Number 1 | May 1989 | Pages 1-21
Technical Paper | doi.org/10.13182/NSE89-A23628
Articles are hosted by Taylor and Francis Online.
A multigrid acceleration scheme for the one-dimensional slab geometry SN equations with anisotropic scattering and linear discontinuous spatial differencing is developed. The high-frequency relaxation iteration consists of three steps: a standard source iteration, independent two-cell block inversions centered about each spatial cell edge, and an averaging of the iterates from the previous two steps. Because the linear discontinuous differencing scheme is a finite element method, fine-to-coarse projection and coarse-to-fine interpolation are straightforward. Although standard linear discontinuous differencing is derived under the assumption of spatially constant cross sections within each cell, the scheme is generalized to allow for a linear spatial variation of the cross section in each cell. This linear variation is required to obtain accurate coarse-grid equations when homogenizing two fine-grid cells with different cross sections into a single coarse-grid cell. This multigrid method is very effective in terms of the spectral radius of the total iteration process, but the computational cost of the block inversions in the second step of the high-frequency relaxation is quite high. However, in optically thick problems with highly anisotropic scattering, this multigrid method is more economical than diffusion synthetic acceleration. Because the block inversions are independent for each cell edge, parallel processing might significantly reduce the cost of the scheme.