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Division Spotlight
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.
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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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.
A. Z. Akcasu
Nuclear Science and Engineering | Volume 10 | Number 4 | August 1961 | Pages 337-345
doi.org/10.13182/NSE61-A15375
Articles are hosted by Taylor and Francis Online.
The dynamic behavior of boiling water reactors at high powers is investigated with a model in which the reactor system is represented by a second-order differential equation with a random damping factor and a random driving function. It is found that the mean square value of power becomes divergent (instability in the mean square sense) at a power level which is lower than the instability threshold usually predicted by the conventional transfer function analysis (instability in the mean). A method for predicting the mean square instability threshold during the initial power rise is also described, which consists of plotting the inverse of the root mean square of the power fluctuations as a function of the average power level, and determining the power at which the extrapolated curve intersects the x axis. The observed occurrence of oscillatory wave trains in the power fluctuations is also accounted for. Some of the results of the model are verified by analogue computer studies.