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Division Spotlight
Young Members Group
The Young Members Group works to encourage and enable all young professional members to be actively involved in the efforts and endeavors of the Society at all levels (Professional Divisions, ANS Governance, Local Sections, etc.) as they transition from the role of a student to the role of a professional. It sponsors non-technical workshops and meetings that provide professional development and networking opportunities for young professionals, collaborates with other Divisions and Groups in developing technical and non-technical content for topical and national meetings, encourages its members to participate in the activities of the Groups and Divisions that are closely related to their professional interests as well as in their local sections, introduces young members to the rules and governance structure of the Society, and nominates young professionals for awards and leadership opportunities available to members.
Meeting Spotlight
2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
Standards Program
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.
A. Galati
Nuclear Science and Engineering | Volume 37 | Number 1 | July 1969 | Pages 30-40
Technical Paper | doi.org/10.13182/NSE69-A20896
Articles are hosted by Taylor and Francis Online.
A quasi-static method is proposed for evaluating spatial effects on nuclear reactor kinetics. The neutron flux shape is calculated approximately as an asymptotic solution of the two-group space-time diffusion equations, where delayed neutron behavior is included. Two iterative procedures are alternatively used according to the amount of reactivity involved. The first one operates until prompt criticality is reached. The second procedure replaces the first one as soon as the reactor goes superpromptcritical. The main feature of the approach adopted is the possibility of selecting an initial guess such that convergence is reached at the first iteration. The matter is then reduced to solving two eigenvalue problems. Theoretical and numerical comparisons with Henry's adiabatic model outline the main role of perturbed adjoint fluxes and correct neutron-flux shape (the second agent only for superpromptcritical excursions) in defining the generation time and reactivity. When compared with the exact solution, results of sample problems show substantial accuracy in the flux shape and amplitude. In subpromptcritical excursions, only the synthesis method is as accurate as the metastatic one and yields errors of few percent at the flux peak. In the reactivity range above prompt critical, differences between the exact results and the metastatic ones are unessential.