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Isotopes & Radiation
Members are devoted to applying nuclear science and engineering technologies involving isotopes, radiation applications, and associated equipment in scientific research, development, and industrial processes. Their interests lie primarily in education, industrial uses, biology, medicine, and health physics. Division committees include Analytical Applications of Isotopes and Radiation, Biology and Medicine, Radiation Applications, Radiation Sources and Detection, and Thermal Power Sources.
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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.
V. Jagannathan, R. P. Jain, Vinod Kumar, H. C. Gupta, P. D. Krishnani
Nuclear Science and Engineering | Volume 104 | Number 3 | March 1990 | Pages 222-238
Technical Paper | doi.org/10.13182/NSE90-A23722
Articles are hosted by Taylor and Francis Online.
A diffusion iterative scheme has been developed to analyze the basic three-dimensional supercell problem encountered in pressurized heavy water reactors (PHWRs). Multigroup transport calculations are performed essentially in one dimension for the fuel cluster cell and the reactivity device (RD) supercell problems. Iterative diffusion calculations are done in one and two dimensions such that the net transport leakages into the fuel cluster or RD are reproduced. The few-group parameters of the fuel cluster or the boundary conditions on the RD surface are modified for this purpose. With these modifications, the three-dimensional supercell problem is treated by diffusion theory. The accuracy of the new scheme is demonstrated against the corresponding transport solutions in both one and three dimensions. A half-bundle-sized constant mesh is proposed for core diffusion analyses. Since the RDs in a PHWR are rather arbitrarily located, it is difficult to perturb the lattice parameters of controlled meshes properly when a constant mesh size is employed. A flux-related weighting scheme is devised to distribute the δ∑’s in meshes falling within the zone of influence of an RD. This core model is compared with a direct method where the supercell concept is avoided and RDs are simulated by internal boundary conditions directly in the core diffusion simulation. Analysis of certain low-power criticals provides the experimental validation of the calculational schemes.