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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.
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.
H. Hurwitz, Jr.
Nuclear Science and Engineering | Volume 23 | Number 2 | October 1965 | Pages 183-187
Technical Paper | doi.org/10.13182/NSE65-A28143
Articles are hosted by Taylor and Francis Online.
Because of the large physical size of typical boiling-water power-reactor cores, there is a possibility of transients in the spatial power distribution. The vertical coolant flow produces a strong undirectional coupling between the power in the lower and upper parts of the core. This situation is qualitatively analyzed by means of a highly simplified two-node reactor model. The additional assumption that the effective delayed-neutron period and fuel-element thermal time constant are equal makes possible a nonlinear graphical solution of the problem by the parametric trajectory method. In the illustrative numerical examples, the spatial power-distribution transients are mild.
