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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
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.
Toshimasa Miura
Nuclear Science and Engineering | Volume 102 | Number 2 | June 1989 | Pages 191-209
Technical Paper | doi.org/10.13182/NSE89-A23643
Articles are hosted by Taylor and Francis Online.
Empirical formulas are derived that describe neutron flux distributions in straight and bent cylindrical steel-walled ducts in symmetrical and asymmetrical geometries. Asymmetry is defined by the slant angle between the duct axis and a line passing through the center of the duct mouth and source. Streaming neutrons are divided into direct, albedo, and penetration components. The first two components are described by a function of the axial distance in units of the square root of the line-of-sight area. The last component is described by a function of the neutron flux distribution in the shield in the absence of the duct. Formulas are applicable to thermal, epithermal, intermediate, and fast neutrons, respectively, in the following range: (a) duct diameter is 5 to 20 cm, (b) duct length is up to 240 cm, (c) slant angle is 0 to 90 deg, (d) steel wall thickness is 0 to 1.0 cm, (e) bent angle is 45 to 90 deg, and (f) surrounding medium of the duct is water or ordinary concrete. Calculations by formulas agree with experimental data, in general, within an accuracy of ±30%.
