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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 Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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Securing the advanced reactor fleet
Physical protection accounts for a significant portion of a nuclear power plant’s operational costs. As the U.S. moves toward smaller and safer advanced reactors, similar protection strategies could prove cost prohibitive. For tomorrow’s small modular reactors and microreactors, security costs must remain appropriate to the size of the reactor for economical operation.
Tsutomu Ikeno, Takeo Kajishima
Nuclear Technology | Volume 158 | Number 2 | May 2007 | Pages 249-260
Technical Paper | Nuclear Reactor Thermal Hydraulics | doi.org/10.13182/NT07-A3840
Articles are hosted by Taylor and Francis Online.
A computational model based on a large-eddy simulation (LES) technique was proposed to estimate turbulent mixing and pressure drop in subchannels with grid spacers. For an efficient treatment of this complex geometry, improvements were made to the LES technique coupled with an immersed boundary method: A one-equation dynamic subgrid scale model was introduced to account for the complex geometry without any artificial modification; the higher order accuracy was maintained by a consistent treatment of boundary conditions for velocity and pressure on solid walls. Computations were carried out for each of the convolute and periodic arrangements with two-step inclinations of the mixing vanes. The results reasonably reproduced the geometric effect in the turbulent mixing and drag coefficients for the flow, including unsteady separation and multiple vortices. The present computational model is useful for designing grid spacers: By coarser mesh, one can screen several candidates for spacer design; by finer mesh, more quantitative analysis is possible.