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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 62 | Number 3 | March 1977 | Pages 502-510
Technical Paper | doi.org/10.13182/NSE77-A26987
Articles are hosted by Taylor and Francis Online.
We report here our calculated results of steady-state space- and angle-dependent thermal-neutron spectra inside an infinite slab as well as inside finite prisms of graphite with transverse dimensions varying from 100 × 100 cm2 to 30 × 30 cm2 and different longitudinal dimensions (ranging from 100 to 180 cm). We find that in the forward direction, due to streaming, cold neutrons pile up with distance. Neutron spectra in backward directions are depleted in sub-Bragg neutrons. At all distances from the source plane, the proportion of cold neutrons in the energy spectrum in the forward direction increases with decrease in transverse dimensions. The question of the existence of asymptotic conditions in these assemblies has been discussed in detail. We show that in the forward direction a true discrete mode does not exist even in an infinite slab 150 cm thick. However, pseudo-asymptotic conditions should exist beyond 30 cm in a prism of transverse dimensions nearly 100 × 100 cm2. The critical transverse dimensions for the existence of a pseudo-asymptotic mode lie somewhere between 100 × 100 cm2 and 70 × 70 cm2, in conformity with the observed results of DeJuren and Swanson and theoretical predictions of Ahmed et al.