ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
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Division Spotlight
Thermal Hydraulics
The division provides a forum for focused technical dialogue on thermal hydraulic technology in the nuclear industry. Specifically, this will include heat transfer and fluid mechanics involved in the utilization of nuclear energy. It is intended to attract the highest quality of theoretical and experimental work to ANS, including research on basic phenomena and application to nuclear system design.
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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August 2024
Latest News
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.
E. Greenspan, Y. Karni
Nuclear Science and Engineering | Volume 69 | Number 2 | February 1979 | Pages 169-190
Technical Paper | doi.org/10.13182/NSE79-A20609
Articles are hosted by Taylor and Francis Online.
Energy-dependent fine-structure effects (FSEs) on the reactivity associated with perturbations in the density and temperature of resonance materials are investigated using a simple single-resonance model Upper and lower bounds to these spectral effects are derived, and parametric studies are performed as a function of the background cross section and resonance structure of the unperturbed assembly and of the type and relative magnitude of the perturbation. It is found that spectral FSEs can be significant even for infinitesimal density or temperature perturbations. The capability of different perturbation theory formulations to account for these FSEs is investigated. The connection between the spectral FSEs and the disagreement of the calculated to the experimentally determined material and Doppler reactivity worth of fuel isotopes in fast critical experiments is also discussed.