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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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Energy is everything
Lisa Marshallpresident@ans.org
Energy is the foundation of modern society. It enhances quality of life and drives industrialization. As we work toward fuller energy transition, policies are essential to organizing our march forward. Bipartisan legislation is doing just that, propelling our current and future actions.
The Accelerating Deployment of Versatile, Advanced Nuclear for Clean Energy (ADVANCE) Act will help propel the work of industry, academia, and several branches of government in exciting—and necessary—directions.
The Senate introduced the act in March 2023, and the House of Representatives passed the Fire Grants and Safety Act, which incorporated the ADVANCE Act, on May 9, 2024 (393–13). Then on June 18, the Senate passed the ADVANCE Act (88–2), and on July 9, President Biden signed the bill into law. New and revised approaches to process and deployment of nuclear energy capacity is well on its way. Below, I have highlighted a few title sections to show scope and significance.
Shigeaki Tsunoyama, Tohru Mitsutake, Shigeo Ebata, Shirley A. Sandoz
Nuclear Technology | Volume 65 | Number 3 | June 1984 | Pages 374-382
Technical Paper | Fission Reactor | doi.org/10.13182/NT84-A33392
Articles are hosted by Taylor and Francis Online.
Applying an autoregressive (AR) technique to a boiling water reactor stability test yields two kinds of reactor stability performance indexes. One is characterized by the neutron flux to reactor pressure open-loop transfer function. The other is characterized by the closed-loop transfer function. Studies were performed on these reactor core stability indexes, using a one-dimensional transient model. To simulate these two kinds of stability characteristics in the time domain, the input/output relation for the system considered is important. In both cases, the output variable is the neutron flux. For the input state variable, in the case of the open-loop stability index, reactor pressure was chosen and adopted as a boundary variable to enable neglecting the feedback due to change in the reactor dome pressure. In the case of the closed-loop stability index, the vessel steam flow to the main steamline was adopted to separate the reactor response from the main steamline. Employing this procedure, both stability indexes were estimated by the one-dimensional reactor transient model. Comparing these indexes to those evaluated by the AR fitting and Fourier transform of small perturbation test data, it was concluded that the one-dimensional transient model predicts well the open- and closed-loop stability performance. Further, it was shown that the open-loop index conventionally used is a somewhat conservative one.