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Division Spotlight
Fusion Energy
This division promotes the development and timely introduction of fusion energy as a sustainable energy source with favorable economic, environmental, and safety attributes. The division cooperates with other organizations on common issues of multidisciplinary fusion science and technology, conducts professional meetings, and disseminates technical information in support of these goals. Members focus on the assessment and resolution of critical developmental issues for practical fusion energy applications.
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.
John R. White, Glenn A. Swanbon
Nuclear Science and Engineering | Volume 105 | Number 2 | June 1990 | Pages 160-173
Technical Paper | doi.org/10.13182/NSE90-A23745
Articles are hosted by Taylor and Francis Online.
The development of a practical approach to higher order generalized perturbation theory (GPT) methods is documented. The method combines a direct correlation technique for obtaining a first-order estimate of the perturbed flux distribution with an explicit representation of second-order GPT for obtaining improved predictions of perturbed integral responses. The technique is easy to use and it does not require extensive methods development efforts; it simply relies on the manipulation of data from several direct perturbation runs and several adjoint computations (and this step can be fully automated). Demonstration cases using a pressurized water reactor benchmark model have verified the adequacy of the method for improving the practicality of using GPT in design applications. The best success to date has been for cases where only a few large localized variations are made. When changes are made at several locations throughout the model, the cancellation of large positive and negative effects tends to introduce increased error in the flux estimates. Current efforts are focused on methods to mitigate some of this numerical cancellation. Overall, the method shows good promise for improving on the use of first-order GPT for application to the core reload design problem.