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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.
Paul J. Turinsky, James J. Duderstadt
Nuclear Science and Engineering | Volume 45 | Number 2 | August 1971 | Pages 156-166
Technical Paper | doi.org/10.13182/NSE71-A20882
Articles are hosted by Taylor and Francis Online.
The substitution of a K-term degenerate kernel expansion (DKE) for the true scattering kernel in the inscattering term for neutron thermalization calculations has been shown to recast the solution of the original speed dependent Fredholm integral operator equation into that of a speed-independent K × K matrix operator equation, which is well suited for numerical calculations: A DKE has been constructed that rapidly converges pointwise to the true scattering kernel, preserves the total scattering cross section, and contains the correct speed structure to yield accurate solutions in neutron thermalization calculations. This DKE was employed in the numerical solution of the steady-state, time-moment, time-eigenvalue, and time-dependent neutron thermalization problems within the framework of asymptotic reactor theory. A detailed numerical investigation of the DKE approximation to the free proton gas and polyethylene scattering kernels indicated that accuracy consistent with a 32 discrete speed mesh point treatment was obtained by employing a 10-term DKE. This implies that the degenerate kernel technique reduces the size of the matrix operator equations to be solved to ∼ ⅓ the size required by a discrete ordinate approach, hence implying considerable computer cost reductions in neutron thermalization calculations.