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Fusion Energy
This division promotes the development and timely introduction of fusion energy as a sustainable energy source with favorable economic, environmental, and safety attributes. The division cooperates with other organizations on common issues of multidisciplinary fusion science and technology, conducts professional meetings, and disseminates technical information in support of these goals. Members focus on the assessment and resolution of critical developmental issues for practical fusion energy applications.
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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.
M. L. Williams
Nuclear Science and Engineering | Volume 70 | Number 1 | April 1979 | Pages 20-36
Technical Paper | doi.org/10.13182/NSE79-3
Articles are hosted by Taylor and Francis Online.
A perturbation formulation is developed for the space-energy-dependent burnup equations describing depletion and transmutation of nuclide densities in a coupled neutron-nuclide field, such as a reactor core. The formulation is developed in a form consistent with the computational methods used for depletion analysis. The analysis technique currently employed in most burnup calculations is first reviewed as a method for describing the nonlinear coupling between the flux and nuclide fields. It is shown that, based on the present formulation, three adjoint equations (for flux shape, flux normalization, and nuclide density) are required to account for the coupled variations arising from variations in initial conditions and nuclear data. The adjoint equations are derived in detail using a variational principle, and an algorithm is suggested for solving the coupled equations backward through time. Perturbation expressions are used to define sensitivity coefficients for responses that depend on the coupled interaction between the neutron and nuclide fields. The relation between coupled and noncoupled sensitivity theory is illustrated. Finally, two analytic example problems are solved that determine the sensitivity of some final nuclide concentration to changes in initial conditions. Results obtained from direct calculation and from the coupled perturbation theory are compared.