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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.
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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. N. Nahavandi, R. F. Von Hollen
Nuclear Science and Engineering | Volume 18 | Number 3 | March 1964 | Pages 335-350
Technical Paper | doi.org/10.13182/NSE64-A20054
Articles are hosted by Taylor and Francis Online.
A set of one-group space-dependent neutron kinetics equations for reactor cores with spatially variable moderator density is developed. The solution to this set of differential equations is obtained numerically using an IBM-7094 digital computer. Employing the variational technique of von Neumann, a numerical stability criterion for space-dependent neutron kinetics equations is established. The present analysis is useful in the determination of the core open-loop response as well as the reactor system transient behavior. The open-loop response of a typical boiling-water reactor core for several values of step change in reactivity was determined using the present analysis. These are shown to be in agreement with the results of the classical space-independent neutron kinetics equations. The open-loop characteristic of the reactor core due to a step change in density distribution is also presented. The main distinguishing feature of the present study is the ability to determine the open-loop response due to disturbances (such as a series of successive step changes in density distribution) for which the classical space-independent approach provides no solution. Characteristics of this type are necessary in the dynamic analysis of boiling-water reactors where the system density distribution varies in time and space. A simple approximate method for the solution of the space-dependent neutron kinetics equations is also presented.
