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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.
George J. Bohm, Amir N. Nahavandi
Nuclear Science and Engineering | Volume 47 | Number 4 | April 1972 | Pages 391-408
Technical Paper | doi.org/10.13182/NSE72-A22431
Articles are hosted by Taylor and Francis Online.
The dynamic analysis of the reactor internal structure in a typical pressurized-water reactor system, subjected to step, periodic, and seismic excitations, is presented. Employing the finite element approach of structural analysis, the governing differential equations describing the motion of the system are set up and integrated numerically in time. It is shown that the introduction of three types of structural elements, elastic, rigid and pin-joint members with nodes having three degrees of freedom, provides an adequate mathematical model for the solution of reactor structural dynamics problems. A main distinctive feature of this analysis is the application of “elements” global stiffness matrices in place of the standard structural global stiffness matrix. It is shown that this feature reduces the computer storage requirement and running time considerably. An examination of the system dynamic response characteristics indicates that when the clearance between the reactor internal components is relatively small, impact between various components could occur. The magnitude of the impact forces for periodic and seismic excitations is computed. Furthermore, a procedure for the calculation of the upper bound of integration time step is presented which ensures the numerical stability of the solution.