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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.
M. S. Trasi
Nuclear Science and Engineering | Volume 10 | Number 3 | July 1961 | Pages 240-246
Technical Paper | doi.org/10.13182/NSE61-A25967
Articles are hosted by Taylor and Francis Online.
The critical condition is obtained for a system consisting of a ring of N equally spaced identical cylindrical rods in a reflected cylindrical reactor. The fluxes in each region are expressed in terms of a Fourier Series expansion of the angular dependence of the flux about each rod. The imposition of the boundary conditions gives a set of linear homogeneous equations, from which the critical determinant is deduced. Matrix theory is used throughout, which facilitates the treatment of the problem, and which in the case of a bare reactor provides a method of elimination of constants alternative to that given by Avery. The derivation is also valid for a system containing a ring of N multiplying or nonmultiplying zones. A little modification of this theory leads, without difficulty, to the solution of the problem of a ring of N control rods, which are “black” to thermal neutrons.