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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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June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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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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College students help develop waste-measuring device at Hanford
A partnership between Washington River Protection Solutions (WRPS) and Washington State University has resulted in the development of a device to measure radioactive and chemical tank waste at the Hanford Site. WRPS is the contractor at Hanford for the Department of Energy’s Office of Environmental Management.
S. Schwarz, K. Fischer, A. Bentaib, J. Burkhardt, J.-J. Lee, J. Duspiva, D. Visser, J. Kyttälä, P. Royl, J. Kim, P. Kostka, R. Liang
Nuclear Technology | Volume 175 | Number 3 | September 2011 | Pages 594-603
Technical Paper | NURETH-13 Special / Reactor Safety | doi.org/10.13182/NT11-A12508
Articles are hosted by Taylor and Francis Online.
Within the course of a hypothetical severe accident in a nuclear power plant, hydrogen can be generated in the primary circuit and released into the containment. Considering the possibility of a deflagration, the simulation of the hydrogen distribution in the containment by computer codes is of major importance. To create a database for code validation, several distribution experiments using helium and hydrogen have been performed in the German Thermal Hydraulics, Hydrogen, Aerosols, Iodine (THAI) facility. The experiments started with the TH13 test, which was the base of the International Standard Problem exercise (ISP-47). TH13 was followed by the Hydrogen-Helium Material Scaling (HM) test series conducted within the Organisation for Economic Co-operation and Development/Nuclear Energy Agency (OECD/NEA) THAI project. The objectives of the HM tests were (a) to confirm the transferability of existing helium distribution test data to hydrogen distribution problems and (b) to understand the processes that lead to the formation and dissolution of a light gas cloud stratification. The HM-2 test was chosen for a code benchmark.During the first phase of the HM-2 test, a light gas cloud consisting of hydrogen and nitrogen was established in the upper half of the facility. In the second phase, steam was injected at a lower position inducing a rising steam-nitrogen plume. The plume did not break through the cloud because its density was higher than the density of the cloud. Therefore, the cloud was gradually dissolved from its bottom.Eleven organizations performed blind calculations for the HM-2 experiment. The lumped parameter (LP) codes ASTEC, COCOSYS, and MELCOR and the computational fluid dynamics (CFD) codes FLUENT, GASFLOW, and GOTHIC were used. The main phenomena were natural convection, interaction between the rising plume and the light gas cloud, steam condensation on walls, fog behavior, and heat up of the walls. The experimental data of the first phase were published, and the atmospheric stratification was simulated reasonably well. The data from the second phase stayed concealed until the simulated results were submitted. The thermal-hydraulic phenomena were well predicted by several LP and CFD contributions, whereas the time intervals needed to dissolve the light gas cloud were either underpredicted or overpredicted. However, the other LP and CFD contributions showed larger deviations in the measured data. Reasons for deviations were identified, and model improvements were demonstrated in open posttest calculations. In this article, the experiment, the benchmark results, and the simulation features are described, and recommendations for code users are given.