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Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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.
A. Z. Akcasu
Nuclear Science and Engineering | Volume 10 | Number 4 | August 1961 | Pages 337-345
doi.org/10.13182/NSE61-A15375
Articles are hosted by Taylor and Francis Online.
The dynamic behavior of boiling water reactors at high powers is investigated with a model in which the reactor system is represented by a second-order differential equation with a random damping factor and a random driving function. It is found that the mean square value of power becomes divergent (instability in the mean square sense) at a power level which is lower than the instability threshold usually predicted by the conventional transfer function analysis (instability in the mean). A method for predicting the mean square instability threshold during the initial power rise is also described, which consists of plotting the inverse of the root mean square of the power fluctuations as a function of the average power level, and determining the power at which the extrapolated curve intersects the x axis. The observed occurrence of oscillatory wave trains in the power fluctuations is also accounted for. Some of the results of the model are verified by analogue computer studies.
