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Division members promote the advancement of mathematical and computational methods for solving problems arising in all disciplines encompassed by the Society. They place particular emphasis on numerical techniques for efficient computer applications to aid in the dissemination, integration, and proper use of computer codes, including preparation of computational benchmark and development of standards for computing practices, and to encourage the development on new computer codes and broaden their use.
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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.
Walter N. Podney, Harold P. Smith, Jr.
Nuclear Science and Engineering | Volume 29 | Number 3 | September 1967 | Pages 373-380
Technical Paper | doi.org/10.13182/NSE67-A17284
Articles are hosted by Taylor and Francis Online.
A simple kinetics model is proposed that describes time dependence of the prompt-neutron population in a cavity reactor in terms of a linear, first-order differential equation for the net thermal-neutron current at the cavity wall. The model is applicable if the cavity albedo changes slowly during a neutron lifetime and does not exceed a specified maximum value. This range of applicability is defined by deriving the kinetics equation on the basis of an age-diffusion theory approximation that describes the time dependence of the thermal-neutron flux at the cavity wall in terms of a Volterra integral equation of the second kind. The method of deriving the kinetics equation suggests a means of experimentally determining the effective multiplication factor and average neutron lifetime-to-fission for more complex cavity geometries by measuring thermal-neutron absorption rate in a nonmultiplying gas in the cavity.