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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.
H. Mösinger
Nuclear Science and Engineering | Volume 76 | Number 2 | November 1980 | Pages 89-102
Technical Paper | doi.org/10.13182/NSE80-A19443
Articles are hosted by Taylor and Francis Online.
A model for two-phase (water-vapor) flow in two-dimensional Cartesian or cylindrical coordinates is described that is implemented in the code DRIX-2D. The model includes slip between the phases and accounts for thermodynamic nonequilibrium. The code was designed as a “best-estimate” model for simulation of loss-of-coolant accidents (LOCAs) in light water reactor safety analysis. In this paper results of DRIX-2D applications are reported that can be used to assess the validity of simplified LOCA models. The main results are that both Cartesian and axisymmetric coordinates in two dimensions show considerable disadvantages as far as the pressure history in the downcomer is concerned. Yet, both models yield acceptable results concerning the gross blowdown behavior. Due to a 90-deg change in flow direction, considerable radial profiles in mass flow rate, velocity, and void fraction establish in the blowdown pipe. Nevertheless, a minor difference in the averaged mass flow rate exists only between a one- and two-dimensionally modeled blowdown pipe. A nonequilibrium state establishes at the pipe inlet in the case of subcooled vessel conditions and is maintained up to the orifice at least for pipe lengths <5m. However, the increase in mass flow rate caused by this nonequilibrium state is generally small enough for typical reactor conditions, so that an equilibrium assumption in the blowdown pipe should be appropriate for LOCA calculations.