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Division Spotlight
Education, Training & Workforce Development
The Education, Training & Workforce Development Division provides communication among the academic, industrial, and governmental communities through the exchange of views and information on matters related to education, training and workforce development in nuclear and radiological science, engineering, and technology. Industry leaders, education and training professionals, and interested students work together through Society-sponsored meetings and publications, to enrich their professional development, to educate the general public, and to advance nuclear and radiological science and engineering.
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.
Bart J. Daly
Nuclear Science and Engineering | Volume 72 | Number 1 | October 1979 | Pages 97-107
Technical Paper | doi.org/10.13182/NSE79-A19312
Articles are hosted by Taylor and Francis Online.
A series of numerical calculations was performed to study the effect of apparatus scale size on the magnitude and duration of emergency core coolant (ECC) bypass and the time delay for refill of the lower plenum of a pressurized water reactor during a hypothetical loss-of-coolant accident. These results indicate that for certain idealized flow and thermal conditions, flow similarity can be obtained at all scale sizes, but that for more realistic conditions, the effects of apparatus scale size and lower plenum pressure on ECC bypass and lower plenum refill can be large. In particular, the duration of ECC bypass and the time delay for refill appear to be more sensitive to momentum exchange at full scale and high lower plenum pressure than they are at 2/15 scale and low pressure. The sensitivity to mass exchange, ECC subcooling, and wall heat transfer decreases with increasing scale and lower plenum pressure. The effect of introducing steam, rather than air, into the downcomer through the broken ECC injection port when the pressure in the downcomer falls below that in the containment vessel is to decrease the rate of lower plenum refill.