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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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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.
S. Dulla, P. Ravetto, M. M. Rostagno, G. Bianchini, M. Carta, A. D'Angelo
Nuclear Science and Engineering | Volume 149 | Number 1 | January 2005 | Pages 88-100
Technical Paper | doi.org/10.13182/NSE149-88
Articles are hosted by Taylor and Francis Online.
The paper considers some physical aspects of the neutron space kinetics of critical and source-driven subcritical systems. The possibility of introducing some indicators to qualify the spatial nature of neutronic transients is investigated. It is shown theoretically and then proved by numerical examples that the separation of the eigenvalues of the mathematical operator defining the problem can be taken as a good indicator of the importance of space effects in time-dependent conditions. To obtain good physical insight into the phenomena, paradigmatically simple configurations are considered, and whenever possible, a fully analytical approach is used. The presented results evidence the limits of applicability of classic simplified models for transient analyses, such as point kinetics. In a second part, the paper considers the open problem of the choice of the weighting function to be used either for the generation of the kinetic parameters of pointlike models or for the exploitation of quasi-static procedures, analyzing comparatively the effect of different options on the results of transient calculations.