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Division Spotlight
Operations & Power
Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
Meeting Spotlight
2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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Candidates announced for 2025 ANS leadership positions
As the U.S. election season finally comes to an end, the annual American Nuclear Society election season is right around the corner. Seventeen candidates have been nominated for the positions of ANS vice president/president-elect, treasurer, and six positions on the board of directors (four U.S. directors, one non-U.S. director, and one student director). Ballots will be sent via email on Tuesday, March 4, 2025, and must be submitted by 1:00 p.m. (EDT) on Tuesday, April 15, 2025.
Maria Pusa, Jaakko Leppänen
Nuclear Science and Engineering | Volume 164 | Number 2 | February 2010 | Pages 140-150
Technical Paper | doi.org/10.13182/NSE09-14
Articles are hosted by Taylor and Francis Online.
The topic of this paper is the computation of the matrix exponential in the context of burnup equations. The established matrix exponential methods are introduced briefly. The eigenvalues of the burnup matrix are important in choosing the matrix exponential method, and their characterization is considered. Based on the characteristics of the burnup matrix, the Chebyshev rational approximation method (CRAM) and its interpretation as a numeric contour integral are discussed in detail. The introduced matrix exponential methods are applied to two test cases representing an infinite pressurized water reactor pin-cell lattice, and the numerical results are presented. The results suggest that CRAM is capable of providing a robust and accurate solution to the burnup equations with a very short computation time.