ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
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Division Spotlight
Thermal Hydraulics
The division provides a forum for focused technical dialogue on thermal hydraulic technology in the nuclear industry. Specifically, this will include heat transfer and fluid mechanics involved in the utilization of nuclear energy. It is intended to attract the highest quality of theoretical and experimental work to ANS, including research on basic phenomena and application to nuclear system design.
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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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.
Suresh Garg, Feroz Ahmed, L. S. Kothari
Nuclear Science and Engineering | Volume 63 | Number 4 | August 1977 | Pages 500-504
Technical Note | doi.org/10.13182/NSE77-A27064
Articles are hosted by Taylor and Francis Online.
We have extended our earlier calculations of steady-state space- and angle-dependent thermalneutron spectra in small beryllium assemblies to assemblies of much greater transverse dimensions and have studied neutron diffusion up to much greater distances from the source plane, with a view toward looking for a discrete mode of decay. We find that in the forward direction, neutron distribution fails to attain equilibrium inside 140-cm-thick assemblies with transverse dimensions of 150 × 150 cm2, whereas in the backward direction, equilibrium is reached even inside an assembly of transverse dimensions of 80 × 80 cm2. We show that in the forward direction, equilibrium is delayed by the presence of a penetrating beam of uncollided sub-Bragg neutrons of the source. Thus, an experimentalist can hardly hope to observe equilibrium in the forward direction. The calculated value of diffusion length is in excellent agreement with the observed as well as the theoretical values obtained by earlier workers.