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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.
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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.
R. D. Lawrence, J. J. Dorning
Nuclear Science and Engineering | Volume 76 | Number 2 | November 1980 | Pages 218-231
Technical Paper | doi.org/10.13182/NSE80-A19452
Articles are hosted by Taylor and Francis Online.
A nodal method for the solution of the multidimensional neutron diffusion equation is developed and evaluated. The method is based on the linear form of the nodal balance equation written in terms of the average partial currents across the surfaces of the node. Green's functions for one-dimensional in-group diffusion-removal operators are used to generate a coupled set of one-dimensional integral equations defined over a subdomain or node. These integral equations represent an exact (local) solution to the coupled set of one-dimensional differential equations obtained by spatially integrating the multidimensional diffusion equation over directions transverse to each coordinate direction. The integral equations are approximated using a weighted residual procedure applied within each node. The resulting matrix equations, when solved in conjunction with the linear form of the nodal balance equation, provide the necessary additional relationships between the interface partial currents and the flux within the node. The nodal method is applied to several two- and three-dimensional light water reactor benchmark problems and to a four-group liquid-metal fast breeder reactor problem. These results demonstrate the capability of the method to yield very accurate steady-state and transient results in significantly smaller computing times than those required by standard finite difference methods.