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Nuclear Nonproliferation Policy
The mission of the Nuclear Nonproliferation Policy Division (NNPD) is to promote the peaceful use of nuclear technology while simultaneously preventing the diversion and misuse of nuclear material and technology through appropriate safeguards and security, and promotion of nuclear nonproliferation policies. To achieve this mission, the objectives of the NNPD are to: Promote policy that discourages the proliferation of nuclear technology and material to inappropriate entities. Provide information to ANS members, the technical community at large, opinion leaders, and decision makers to improve their understanding of nuclear nonproliferation issues. Become a recognized technical resource on nuclear nonproliferation, safeguards, and security issues. Serve as the integration and coordination body for nuclear nonproliferation activities for the ANS. Work cooperatively with other ANS divisions to achieve these objective nonproliferation policies.
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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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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.
Yanheng Li, Wei Ji
Nuclear Science and Engineering | Volume 173 | Number 2 | February 2013 | Pages 150-162
Technical Paper | doi.org/10.13182/NSE12-13
Articles are hosted by Taylor and Francis Online.
In pebble bed reactors (PBRs), pebble flow and coolant flow are highly correlated, and the behavior of each flow is strongly influenced by pebble-coolant interactions. Simulation of both flows in PBRs presents a multiphysics computational challenge because of the strong interplay between the flows. In this paper, a fully coupled multiphysics model is developed and applied to analyze the pebble flow and coolant flow in helium gas-cooled and fluoride salt-cooled PBR designs. A discrete element method is used to simulate the pebble motion to obtain the distribution of pebble density and velocity and the maximum contact stress on each pebble. Computational fluid dynamics is employed to simulate coolant dynamics to obtain the distribution of coolant velocity and pressure. The two methods are fully coupled through the calculation and exchange of pebble-coolant interactions at each time step. Thus, a fully coupled multiphysics computational framework is formulated. A scaled experimental fluoride salt-cooled reactor facility and a full-core helium gas-cooled HTR-10 reactor are simulated. Noticeable changes, such as higher pebble density in the cylindrical core region and more uniform vertical fluid speed profile due to the coupling effect, are observed compared to previous single-phase simulations alone without coupling. These changes suggest that the developed computational framework has higher fidelity compared with previous uncoupled methodology in analyzing pebble flow in PBRs. For the scaled experimental fluorite salt-cooled reactor facility calculation, similar hydraulic loss can be obtained as measured in the University of California, Berkeley, Pebble Recirculation Experiment (PREX), demonstrating the potential of the developed method in thermal-hydraulic analysis for PBRs.