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Division Spotlight
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.
Meeting Spotlight
2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
Standards Program
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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August 2024
Latest News
NRC issues interim guidance on reactor component disposal
The Nuclear Regulatory Commission is providing guidance to nuclear power plant licensees looking to use decommissioning trust fund (DTF) money to dispose of major reactor components like steam generators and reactor vessel heads while the plant is still operational.
On August 5, the NRC issued the interim staff guidance Use of the Decommissioning Trust Fund During Operations for Major Radioactive Component Disposal (REFS-ISG-2024-01), which provides the NRC staff’s regulatory position regarding the use a reactor’s DTF for the disposal of major radioactive components while the plant is still operational. Under NRC regulations, the DTF may be accessed solely for decommissioning expenses as defined in 10 CFR 50.2, unless an exemption is granted by the NRC.
Dillon R. Shaver, Nate Salpeter, Ananias Tomboulides, Prasad Vegendla, Adrian Tentner, W. David Pointer, Elia Merzari
Nuclear Technology | Volume 206 | Number 2 | February 2020 | Pages 375-387
Technical Paper | doi.org/10.1080/00295450.2019.1664199
Articles are hosted by Taylor and Francis Online.
To enable the design of a light water small modular reactor, the boiling flow inside a helical coil steam generator has been simulated with the two-fluid model in Nek-2P. Nek-2P is the multiphase branch of the spectral element code Nek5000. Details of the implementation of the two-fluid model and the included closure models are discussed. The presented closure models include interactions for momentum, heat, and mass transfer between phases. Models for the drag, lift, and turbulent dispersion forces are included. The complete model is fully consistent in the limits of both phasic volume fractions approaching zero and is able to simulate flows of dispersed vapor, continuous liquid, dispersed liquid, continuous vapor, or any combination thereof. The closure models and their implementation in Nek-2P have been validated by comparing to experimental data for a boiling flow, demonstrating excellent agreement. Results from the simulation of the helical coil indicate strong phasic separation driven by the effects of buoyancy and inertia. Significant differences were observed in the results compared to simulations performed using Star-CCM+, although these differences were somewhat expected.