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Division Spotlight
Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
Meeting Spotlight
2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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
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.
Hussein Khalil
Nuclear Science and Engineering | Volume 90 | Number 3 | July 1985 | Pages 263-280
Technical Paper | doi.org/10.13182/NSE85-A17768
Articles are hosted by Taylor and Francis Online.
A diffusion theory method is developed for synthetic acceleration of nodal Sn calculations in multidimensional Cartesian geometries. The diffusion model is derived from the spatially continuous diffusion equation by applying spatial approximations that are P1 expansions of the corresponding approximations made in solving the transport equation. The equations of the diffusion model are formulated in a way that permits application of existing and highly efficient nodal diffusion theory techniques to their numerical solution. Test calculations for several benchmark problems in X-Y geometry are presented to illustrate the efficiency and stability of the acceleration method when applied to a “constant-linear” nodal transport approximation. The method is shown to yield point-wise flux convergence of 10-4 in fewer than ten synthetic iterations for all problems considered and to require substantially less computational effort than unaccelerated solutions.