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Reactor Physics
The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
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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.
Keith E. Holbert, Nikhil Venkatesh
Nuclear Science and Engineering | Volume 119 | Number 3 | March 1995 | Pages 203-211
Technical Note | doi.org/10.13182/NSE95-A24086
Articles are hosted by Taylor and Francis Online.
The value of the moderator temperature coefficient (MTC) of reactivity is contained in correlations between fluctuations of the neutron flux and core-exit coolant temperature. The absolute magnitude of the MTC is obtained from noise analysis by using the root-mean-square method and the frequency response function technique. Both approaches are used in conjunction with the phase angle method, which determines the MTC sign, to obtain complete information about the MTC. Analytical expressions that are derived show that a limitation exists on the range of MTC values for which the cross-power spectral density phase angle can be used to establish the MTC sign. This research shows that small positive values of the MTC (an unstable condition) can result in a —180-deg phase angle shift, contrary to earlier studies that indicated a stable reactor. The range of sign determinate MTC values is dependent on the driving noise source. Simulated noise data are generated for different MTC values and analyzed to verify the theoretical work. A comparison of the indeterminate regions to allowable MTC values for an operating pressurized water reactor is also presented.