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Human Factors, Instrumentation & Controls
Improving task performance, system reliability, system and personnel safety, efficiency, and effectiveness are the division's main objectives. Its major areas of interest include task design, procedures, training, instrument and control layout and placement, stress control, anthropometrics, psychological input, and motivation.
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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.
P. Köhler, J. Ligou
Nuclear Science and Engineering | Volume 54 | Number 3 | July 1974 | Pages 357-360
Technical Note | doi.org/10.13182/NSE74-A23426
Articles are hosted by Taylor and Francis Online.
Calculations of neutron streaming in gas-cooled fast reactors (GCFR) designed with fuel pins have not been made properly up to now. The usual approach for computing the diffusion coefficients fails for two reasons: (a) the voided region is located at the cell boundary, and (b) the pitch is such that two-dimensional infinite gaps extend through the reactor. For an infinite lattice, the diffusion coefficient will diverge, which means that, in principle, the diffusion theory is no longer valid. This fact has been more or less forgotten because most theories assume cylindrical cells and therefore remove this difficulty artificially. Introducing the real size of the reactor at the beginning, a new theory of the streaming, which generalizes the usual approach is developed; it appears as a buckling dependent term in the diffusion coefficient which diverges slowly for an infinite lattice. Fortunately, this term is small for usual reactor sizes, and one may, therefore, continue to use diffusion theory for practical calculations. The numerical applications to GCFR lattices show that the streaming was underestimated in the past.