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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.
Thomas M. Evans, Kevin T. Clarno, Jim E. Morel
Nuclear Science and Engineering | Volume 165 | Number 3 | July 2010 | Pages 292-304
Technical Paper | doi.org/10.13182/NSE09-28
Articles are hosted by Taylor and Francis Online.
We have developed a modification of the two-grid upscatter acceleration scheme of Adams and Morel. The modified scheme uses a low-angular-order discrete ordinates equation to accelerate Gauss-Seidel multigroup iteration. This modification ensures that the scheme does not suffer from consistency problems that can affect diffusion-accelerated methods in multidimensional, multimaterial problems. The new transport two-grid scheme is very simple to implement for different spatial discretizations because it uses the same transport operator. The scheme has also been demonstrated to be very effective on three-dimensional, multimaterial problems. On simple one-dimensional graphite and heavy-water slabs modeled in three dimensions with reflecting boundary conditions, we see reductions in the number of Gauss-Seidel iterations by factors of 75 to 1000. We have also demonstrated the effectiveness of the new method on neutron well-logging problems. For forward problems, the new acceleration scheme reduces the number of Gauss-Seidel iterations by more than an order of magnitude with a corresponding reduction in the run time. For adjoint problems, the speedup is not as dramatic, but the new method still reduces the run time by greater than a factor of 6.