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Division Spotlight
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.
Meeting Spotlight
Conference on Nuclear Training and Education: A Biennial International Forum (CONTE 2025)
February 3–6, 2025
Amelia Island, FL|Omni Amelia Island Resort
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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Latest News
Senate committee hears from energy secretary nominee Chris Wright
Wright
Chris Wright, president-elect Trump’s pick to lead the U.S. Department of Energy, spent hours today fielding questions from members of the U.S. Senate’s committee on Energy and Natural Resources.
During the hearing, Wright—who’s spent most of his career in fossil fuels—made comments in support of nuclear energy and efforts to expand domestic generation in the near future. Asked what actions he would take as energy secretary to improve the development and deployment of SMRs, Wright said: “It’s a big challenge, and I’m new to government, so I can’t list off the five levers I can pull. But (I’ve been in discussions) about how to make it easier to research, to invest, to build things. The DOE has land at some of its facilities that can be helpful in this regard.”
Temitope A. Taiwo, A. F. Henry
Nuclear Science and Engineering | Volume 92 | Number 1 | January 1986 | Pages 34-41
Technical Paper | doi.org/10.13182/NSE86-A17862
Articles are hosted by Taylor and Francis Online.
The standard point kinetics equations and formally exact expressions for reactivity, prompt neutron lifetime, and effective delayed neutron fractions are derived from the matrix form of the nodal code QUANDRY. Perturbation theory expressions for reactivity based both on the standard quadratic-transverse-leakage form of QUANDRY and on the coarse-mesh finite difference (CMFD) form, made accurate by the use of discontinuity factors, are derived. With three-dimensional CMFD QUANDRY transient calculations taken as numerical standards, the accuracy of several standard point kinetics methods as well as the improved quasi-static method is tested. Results suggest that point kinetics methods are poor for rod ejection calculations, even if a precalculated table of rod worth versus position is used to infer the reactivity contribution of the moving rods. For transients not involving rod motion, the point kinetics equations are more accurate. Use of core-averaged (rather than node-dependent) temperature coefficients, however, can produce significant errors. The quasistatic scheme appears to yield acceptably accurate results but, for the tests run, consistently required more computing time than needed for the full three-dimensional solutions.