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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.
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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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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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Commercial nuclear innovation "new space" age
In early 2006, a start-up company launched a small rocket from a tiny island in the Pacific. It exploded, showering the island with debris. A year later, a second launch attempt sent a rocket to space but failed to make orbit, burning up in the atmosphere. Another year brought a third attempt—and a third failure. The following month, in September 2008, the company used the last of its funds to launch a fourth rocket. It reached orbit, making history as the first privately funded liquid-fueled rocket to do so.
Jim E. Morel, James S. Warsa
Nuclear Science and Engineering | Volume 156 | Number 3 | July 2007 | Pages 325-342
Technical Paper | doi.org/10.13182/NSE06-13
Articles are hosted by Taylor and Francis Online.
We consider two general finite-element lumping techniques for the Sn equations with discontinuous finite-element spatial discretization and apply them to quadrilateral meshes in x-y geometry. One technique is designed to ensure a conservative approximation and is referred to as conservation preserving (CP). The other technique is designed to preserve the exact solution whenever it is contained within the trial space and is referred to as solution preserving (SP). These techniques are applied in x-y geometry on structured nonorthogonal grids using the bilinear-discontinuous finite-element approximation. The schemes are both theoretically analyzed and computationally tested. Analysis shows that the two lumping schemes are equivalent on parallelogram meshes. Computational results indicate that both techniques perform extremely well on smooth quadrilateral meshes. On nonsmooth meshes, the preserving technique retains its excellent performance while the CP technique degrades. The reasons for this degradation are discussed. Although the SP scheme has proven to be generally effective on quadrilateral meshes in x-y geometry, it is not expected to be effective for quadrilaterals in r-z geometry or for hexahedra in three-dimensional Cartesian geometry. Thus, a full lumping procedure for general nonorthogonal meshes that possesses all of the desired properties has yet to be found. For reasons that are discussed, it appears unlikely that such a procedure exists.