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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.
Jeffrey A. Favorite
Nuclear Science and Engineering | Volume 155 | Number 2 | February 2007 | Pages 321-329
Technical Paper | Mathematics and Computation, Supercomputing, Reactor Physics and Nuclear and Biological Applications | doi.org/10.13182/NSE07-A2666
Articles are hosted by Taylor and Francis Online.
Standard variational estimates for perturbations in inhomogeneous transport problems were applied to internal-interface perturbations in coupled neutron-photon problems. Absolute gamma-ray line leakages and ratios of line leakages were the quantities of interest. Gamma-ray spectroscopy using the deterministic multigroup discrete-ordinates code PARTISN was accomplished with a 130-group neutron library and a 120-group photon library with narrow bins centered around gamma lines of interest. Perturbed integrals were evaluated using a volume and a surface formulation, and issues involving negative fluxes (required in the adjoint calculation for line ratios) were addressed. Numerical test problems used a 252Cf source surrounded by a material containing nitrogen and hydrogen; the thickness of this material was perturbed ±86%. The ratios of the 1.8848-, 2.2246-, and 5.2692-MeV thermal neutron capture lines were very well estimated using the variational estimates, even for macroscopic-size perturbations of internal interface locations; the volume-integral formulation for the perturbed integrals was generally more accurate than the surface-integral formulation for estimating ratios. For estimating absolute leakages, the Roussopolos functional in the surface-integral formulation was clearly superior when the gamma-producing shell was thickened, but it produced negative estimates when the shell was thinned.