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Isotopes & Radiation
Members are devoted to applying nuclear science and engineering technologies involving isotopes, radiation applications, and associated equipment in scientific research, development, and industrial processes. Their interests lie primarily in education, industrial uses, biology, medicine, and health physics. Division committees include Analytical Applications of Isotopes and Radiation, Biology and Medicine, Radiation Applications, Radiation Sources and Detection, and Thermal Power Sources.
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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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Latest News
Aalo and Idaho Falls Power reach agreement on potential microreactor siting
Microreactor developer Aalo Atomics municipal electric utility Idaho Falls Power have developed a memorandum of understanding that could lead to the siting of seven sodium-cooled microreactors and a power purchase agreement for Idaho Falls.
Yousef M. Farawila
Nuclear Science and Engineering | Volume 129 | Number 3 | July 1998 | Pages 261-272
Technical Paper | doi.org/10.13182/NSE98-A1980
Articles are hosted by Taylor and Francis Online.
A modal neutron kinetics method was developed and applied to new problems with boiling water reactor oscillations. The modal method is uniquely suited for such problems because the oscillation components, in-phase and out-of-phase, correspond directly to separate expansion functions. One problem is understanding the origin and predicting the magnitude of the in-phase component that is always present during out-of-phase power oscillations. Another exercise of the method was the calculation of the relative critical power ratio (CPR) response to in-phase and out-of-phase oscillations, known as the DIVOM curve, using a fast single hydraulic channel model. The new calculations confirm the BWR owners group results and similar calculations using the full three-dimensional neutronics and multichannel models of the RAMONA-3 code. In addition, the origin of the large difference between the in-phase and out-of-phase CPR responses could be explained. Modal analysis of the reactivity biases associated with oscillating reactivity insertions for the two known modes could explain the out-of-phase mode higher propensity to growth compared with the in-phase mode of oscillation.