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
Robotics & Remote Systems
The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
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!
Latest Magazine Issues
Aug 2024
Jan 2024
Latest Journal Issues
Nuclear Science and Engineering
October 2024
Nuclear Technology
Fusion Science and Technology
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.
Frej Wasastjerna
Nuclear Science and Engineering | Volume 115 | Number 3 | November 1993 | Pages 273-278
Technical Note | doi.org/10.13182/NSE93-A24056
Articles are hosted by Taylor and Francis Online.
The neutron source to be used in calculations of the irradiation of nuclear reactor pressure vessels depends not only on the power distribution in the core but also on the burnup distribution. The burnup affects both the strength and the spectrum of the source, with each effect increasing the displacement rate in the pressure vessel as the burnup in the outer parts of the core increases. For a VVER-440 reactor, each effect causes an ≈8 % increase going from fresh fuel to a burnup representative of a low-leakage loading scheme. For Western light water reactors, the increase due to the spectral effect may be somewhat larger. This work investigates the spectral effect and discusses practical ways of taking it into account in calculations.