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Radiation Protection & Shielding
The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
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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.
Bertram Wolfe, David Fischer
Nuclear Science and Engineering | Volume 5 | Number 1 | January 1959 | Pages 5-10
Technical Paper | doi.org/10.13182/NSE59-A27321
Articles are hosted by Taylor and Francis Online.
The perturbation approach to control element evaluation is extended from the work presented in a previous paper. A two-group second-order perturbation expression for control element worth is obtained. This has, as its starting point, the unperturbed fast flux but considers the depression in the thermal flux caused by the control element and then, in turn, considers the perturbation on the fast flux caused by the perturbed thermal flux. Finally, the effect of the perturbed fast flux on the thermal flux is evaluated. It is shown that this process, if continued, converges to the correct answer. The perturbation results are compared to experiments for the case of a weak rod in the reflector region of the Bulk Shielding Reactor. The perturbation results are also compared to exact two-group calculations for a cylindrical rod on the axis of a bare cylindrical reactor. In both cases, excellent agreement is obtained.