ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
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Division Spotlight
Thermal Hydraulics
The division provides a forum for focused technical dialogue on thermal hydraulic technology in the nuclear industry. Specifically, this will include heat transfer and fluid mechanics involved in the utilization of nuclear energy. It is intended to attract the highest quality of theoretical and experimental work to ANS, including research on basic phenomena and application to nuclear system design.
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.
J. Devooght, H. B. Smets
Nuclear Science and Engineering | Volume 28 | Number 2 | May 1967 | Pages 226-236
Technical Paper | doi.org/10.13182/NSE67-A17472
Articles are hosted by Taylor and Francis Online.
Nonlinear stability criteria for reactors (Welton, Popov, etc.) can only be used when the reactor is linearly stable at all equilibrium power levels. This paper contains four methods of analysis of nonlinear stability that can be used when the reactors are unstable above a certain equilibrium power. The topological method and the second Liapunov method are often of no practical interest, while the Aizermann and Rosen methods are applicable irrespective of the complexity of the system. The different methods are compared in the case of a reactor with a prompt-positive temperature coefficient and a slow-negative temperature coefficient.