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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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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.
J. E. Cahalan, K. O. Ott
Nuclear Science and Engineering | Volume 50 | Number 3 | March 1973 | Pages 208-215
Technical Paper | doi.org/10.13182/NSE73-A28973
Articles are hosted by Taylor and Francis Online.
The delayed neutron precursor decay curves which result from a pulse of fissions of the isotopes 233 U, 235U, 238U, 232Th, 239Pu, 240Pu, 241Pu, and242Pu are consistently fit to a single set of six isotope-independent decay constants. When delayed neutron yields based on a single set of group decay constants are employed in reactor transient analysis, it becomes possible to introduce macroscopic precursor production cross sections for each of the delayed neutron groups. The newly fitted data are tested by the analysis of a typical fast reactor transient; the analysis shows that the utilization of the new data in comparison to the use of original data results in an insignificantly small deviation, while permitting a considerable reduction of calculational effort. The new technique developed for the fitting is shown to preserve important integral kinetics parameters. The fitting technique also allows the recasting of original five group data into the more conventional six group structure.Recent measurements on the energy dependence of delayed neutron yields and emission spectra are briefly discussed. The lack of energy dependence of the total delayed neutron yield in the range of interest for fast reactor analysis leads to a modification of the definition of the effective delayed neutron fraction.