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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
ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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
Norway’s Halden reactor takes first step toward decommissioning
The government of Norway has granted the transfer of the Halden research reactor from the Institute for Energy Technology (IFE) to the state agency Norwegian Nuclear Decommissioning (NND). The 25-MWt Halden boiling water reactor operated from 1958 to 2018 and was used in the research of nuclear fuel, reactor internals, plant procedures and monitoring, and human factors.
Kazys K. Almenas, Yih-Yun Hsu, Marino Dimarzo, Zen-You Wang, Gary A. Pertmer, Richard Lee
Nuclear Technology | Volume 82 | Number 3 | September 1988 | Pages 341-354
Technical Paper | Heat Transfer and Fluid Flow | doi.org/10.13182/NT88-A34135
Articles are hosted by Taylor and Francis Online.
A sufficiently large data base of repeated integral thermal-hydraulic loop tests has been accumulated recently from which generalized conclusions can be drawn. Evidence obtained from experiments performed in the University of Maryland College Park (UMCP) loop show that qualitative as well as quantitative differences exist between integral and separate effect tests. For separate effect tests, flow conditions are controlled continuously and usually steady (or quasi-steady) states are of interest. Integral facilities are “closed” systems and reactor safety oriented investigations center on transient behavior for which only initial conditions can be specified. It is shown that integral flow systems have a generic capability of amplifying (or damping) small perturbations and usually can operate in one of several possible alternate flow states. These characteristics can lead to two distributions of interexperiment variations; the differences can follow a Gaussian distribution or a bifurcation. In the UMCP test program, several examples of repeat experiments whose trajectories fall outside a Gaussian distribution were observed. Such experimental results have implications for the planning of experimental test programs and for the verification process of computational models.