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Operations & Power
Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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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RP3C Community of Practice’s fifth anniversary
In February, the Community of Practice (CoP) webinar series, hosted by the American Nuclear Society Standards Board’s Risk-informed, Performance-based Principles and Policies Committee (RP3C), celebrated its fifth anniversary. Like so many online events, these CoPs brought people together at a time when interacting with others became challenging in early 2020. Since the kickoff CoP, which highlighted the impact that systems engineering has on the design of NuScale’s small modular reactor, the last Friday of most months has featured a new speaker leading a discussion on the use of risk-informed, performance-based (RIPB) thinking in the nuclear industry. Providing a venue to convene for people within ANS and those who found their way online by another route, CoPs are an opportunity for the community to receive answers to their burning questions about the subject at hand. With 50–100 active online participants most months, the conversation is always lively, and knowledge flows freely.
D. Squarer, L. E. Hochreiter, A. T. Pieczynski
Nuclear Technology | Volume 65 | Number 1 | April 1984 | Pages 16-22
Technical Paper | Postaccident Debris Cooling / Heat Transfer and Fluid Flow | doi.org/10.13182/NT84-A33368
Articles are hosted by Taylor and Francis Online.
In the worst hypothetical accident in a light water reactor, when all protection systems fail, the core could be converted into a deep particulate bed either in-vessel or ex-vessel. The containment of such an accident depends on the coolability of a heat-generating debris bed. Some recent experimental and analytical studies that are concerned with heat removal from such a particulate bed are reviewed. Studies have indicated that bed dryout flux and, therefore, the heat removal rate from the particulate bed increases with the particle diameter (i.e., the permeability) for pool boiling conditions and can exceed the critical heat flux of a flat plate. Bed dryout in a large particle bed (i.e., a few millimetres) was found to be closely related to the “flooding” limit of the bed. Dryout under forced flow conditions was found to be affected by both forced and natural convection for mass flow rate smaller than whereas above this mass flow rate, bed dryout is proportional to the mass flow rate. Recent analyses were found to be in agreement with experimental data; however, additional research is needed to assess factors not accounted for in previous studies (e.g., effect of pressure, multidimensionality, stratification, etc.). Based on the expected pressure and particle sizes in a postulated severe accident sequence, a debris bed should be coolable, given a sufficient water supply.