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Robotics & Remote Systems
The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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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New laws offer nuclear industry incentives for existing power plant uprates
This year, the U.S. nuclear industry received a much-needed economic boost that could help preserve operating nuclear power plants and incentivize upgrades that extend their lifespan and power output.
Signed into law in 2022, the Inflation Reduction Act offers production tax credits (PTCs) for existing nuclear power plants and either PTCs or investment tax credits (ITCs) for new carbon-free generation. These credits could make power uprates—increasing the maximum power level at which a commercial plant may operate—a much more appealing option for utilities.
Gabriele Grassi
Nuclear Science and Engineering | Volume 155 | Number 2 | February 2007 | Pages 208-222
Technical Paper | Mathematics and Computation, Supercomputing, Reactor Physics and Nuclear and Biological Applications | doi.org/10.13182/NSE07-A2657
Articles are hosted by Taylor and Francis Online.
A new space-angle multigrid technique has been developed to accelerate the free inner transport iterations based upon the method of characteristics (MOC). We present a two-level scheme that consists of a fine level on which the MOC transport calculation is performed and a more coarsely discretized phase-space in which a low-order problem is solved as an acceleration step. A flux-volume homogenization technique is employed to define the coarse-level cross sections. This entails the nonlinearity of the scheme. Restriction and prolongation operators are defined between the two levels. After each fine transport iteration, a low-order transport problem is iteratively solved on the homogenized grid. A coarser angular representation is used within an MOC-like framework. Discontinuity factors are employed to reconstruct the scalar incoming and outgoing currents on each region of the coarse discretization. The solution of the aforementioned low-order problem is used to correct the angular moments of the flux resulting from the previous free transport sweep. A complete description of the low-order operator and of the grid-to-grid transfer operators is given. A further application of the method to the acceleration of outer transport iterations is also presented. In order to test the effectiveness of this method, numerical tests for given benchmark geometries have been performed. Results are discussed.