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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
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
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
Argonne’s METL gears up to test more sodium fast reactor components
Argonne National Laboratory has successfully swapped out an aging cold trap in the sodium test loop called METL (Mechanisms Engineering Test Loop), the Department of Energy announced April 23. The upgrade is the first of its kind in the United States in more than 30 years, according to the DOE, and will help test components and operations for the sodium-cooled fast reactors being developed now.
A. F. Henry
Nuclear Science and Engineering | Volume 20 | Number 3 | November 1964 | Pages 338-351
Technical Paper | doi.org/10.13182/NSE64-A19579
Articles are hosted by Taylor and Francis Online.
For a large power reactor it appears possible to describe nonseparable space-time kinetics transients in terms of a particular set of spatial harmonics to be called inhour modes. These modes are defined as a subset of the period modes obtained by assuming a separable time variation ewt for all variables in the source-free, time-dependent neutron and neutron-precursor equations. Their use is appropriate whenever details of the neutron energy and angular behavior are not required. Inhour modes are shown to occur in clusters of seven, the seven eigenvalues of a given cluster being obtained as the roots of an inhour equation appropriate to the cluster. The neutron flux shapes associated with a particular cluster of seven modes are all approximately the same. It is shown that if these shapes are assumed to be identical, certain useful orthogonality relations and certain identities involving the roots of the inhour formula for a given cluster are obtained. Use of these results simplifies the extension of the conventional equations of reactor kinetics to the nonseparable case. Inhour modes are also useful in analyzing certain experiments involving subcritical assemblies. As an illustration, application to the source-jerk and pulsed-source experiments is made.