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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.
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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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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. England, J. P. Hennart, J. G. Martin, L. Melendez L., S. M. Waller
Nuclear Science and Engineering | Volume 64 | Number 1 | September 1977 | Pages 132-140
Technical Paper | doi.org/10.13182/NSE77-A27084
Articles are hosted by Taylor and Francis Online.
Fluid equations for a low-beta plasma, where the ratio of the kinetic to the magnetic pressure is small, constitute a system of parabolic partial-differential equations. Depending on the particular assumptions made, this may be a system of three equations for density, electron temperature, and ion temperature, or a single density equation, or a system of four equations where the current density or magnetic field also has to be determined. Such equations were previously solved by one-dimensional models, imposing some additional form of symmetry. In two dimensions, strongly anisotropic diffusion coefficients cause a spurious numerical loss of plasma. This problem was tackled in various geometries for the single density equation, and adequate mass conservation methods were developed. The two principal components of the diffusion were separated and, by a method of fractional steps, were treated by distinct methods. The diffusion parallel to the magnetic field was treated as a one-dimensional problem by two different techniques, (a) using a nonstandard Galerkin finite element, and (b) resulting from an averaging process across a flux tube. Meanwhile, the perpendicular diffusion, when treated by a Galerkin finite element method, gives rise to very wide band matrices, a problem that can be resolved advantageously by using the alternating direction implicit method.