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Aerospace Nuclear Science & Technology
Organized to promote the advancement of knowledge in the use of nuclear science and technologies in the aerospace application. Specialized nuclear-based technologies and applications are needed to advance the state-of-the-art in aerospace design, engineering and operations to explore planetary bodies in our solar system and beyond, plus enhance the safety of air travel, especially high speed air travel. Areas of interest will include but are not limited to the creation of nuclear-based power and propulsion systems, multifunctional materials to protect humans and electronic components from atmospheric, space, and nuclear power system radiation, human factor strategies for the safety and reliable operation of nuclear power and propulsion plants by non-specialized personnel and more.
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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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.
Robert P. Rulko
Nuclear Science and Engineering | Volume 121 | Number 3 | December 1995 | Pages 371-392
Technical Paper | doi.org/10.13182/NSE95-A24141
Articles are hosted by Taylor and Francis Online.
Historically, the even-order PN equations have been considered a less accurate approximation to the transport equation than the odd-order PN-1 equations. This perception has stemmed from two apparent conceptual difficulties imposed by the even-order PN methods— the difficulty in prescribing rigorous boundary conditions for even-order PN equations that contain the odd number of angular flux moments and the discontinuous character of the even-order PN solutions at material interfaces. With the first one of the mentioned even-order PN conceptual problems, a presentation is made of a straightforward and physically-motivated variational procedure based on a new functional that leads from a multigroup planar geometry transport problem to a multigroup P2 problem with clearly and rigorously defined multigroup boundary conditions. These boundary conditions are new and allow neutron transfer between energy groups at the boundary. These boundary conditions are tested by comparing P2, P1, and SN calculations. Our results show that in the test problems considered, the multigroup P2 equations with variational boundary conditions are always more accurate than the P1 multigroup equations with Federighi-Pomraning or Marshak boundary conditions applied to each energy group.