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The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
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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.
John G. Kollas and Allan F. Henry
Nuclear Science and Engineering | Volume 60 | Number 4 | August 1976 | Pages 464-471
Technical Note | doi.org/10.13182/NSE76-A26907
Articles are hosted by Taylor and Francis Online.
A method for obtaining homogenized group-diffusion-theory parameters for heterogeneous nodes (fuel regions plus control elements plus structure) in slab geometry is described. The parameters obtained reproduce exactly the neutron leakage and the integrated reaction rates of the node when it becomes part of a reactor. However, for asymmetric nodes they depend on the fluxes and currents at the surfaces of the node. The sensitivity of this dependence is examined for a one-group model, and numerical examples are given to illustrate that for symmetric nodes, the equivalent parameters are indeed exact and independent of conditions outside the node. For unsymmetric nodes, it is shown that using a set of parameters that is an average of two sets of “exact parameters,” one appropriate to large values of current-to-flux ratio at one of the nodal surfaces and the other appropriate to small values, still yields quite accurate results. For both cases comparisons with results obtained using standard flux-weighted parameters are made.