ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
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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Nuclear Science and Engineering
October 2024
Nuclear Technology
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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.
Zoltan R. Rosztoczy and Lynn E. Weaver
Nuclear Science and Engineering | Volume 20 | Number 3 | November 1964 | Pages 318-323
Technical Paper | doi.org/10.13182/NSE64-A19576
Articles are hosted by Taylor and Francis Online.
The buildup of xenon poisoning is a prime factor in restarting a high-flux thermal reactor after shutdown. To restart the reactor at any time, sufficient excess reactivity must be present to override the xenon poisoning. The amount of excess reactivity required can be minimized by determining an optimum reactor shutdown program. Based on Pontryagins Maximum Principle, optimum shutdown programs are determined for various flux levels ranging from 1014n/cm2 sec. to 1016n/cm2sec. Results show that a considerable reduction in the peak value of xenon concentration can be realized by relatively simple shutdown programs.