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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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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.
G. C. Pomraning, C. A. Stevens
Nuclear Science and Engineering | Volume 55 | Number 4 | December 1974 | Pages 359-367
Technical Paper | doi.org/10.13182/NSE74-A23469
Articles are hosted by Taylor and Francis Online.
The transport and diffusion equations appropriate for performing neutronic and photonic calculations in toroidal geometry are derived. This geometry is an important one in current conceptual designs of controlled thermonuclear reactors. It is shown that for an azimuthally independent problem, the toroidal diffusion equation can be cast into the standard r-θ cylindrical equation by appropriately redefining the diffusion coefficient, absorption cross section, and external source. A Fourier expansion of the diffusion equation to obtain the theta dependence of the flux is shown to have the same truncation properties as those associated with the spherical harmonics method. A more useful expansion is one in inverse powers of the aspect ratio of the toroidal system. An idealized problem is solved analytically to obtain the first-order correction term arising from the overall curvature of the toroidal system. For an aspect ratio of three, typical of Tokamak fusion reactors now under consideration, this result indicates that local errors in the flux in excess of 15% can arise if the toroidal character of the geometry is neglected.