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Division Spotlight
Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
Meeting Spotlight
2025 ANS Annual Conference
June 15–18, 2025
Chicago, IL|Chicago Marriott Downtown
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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Latest News
ANS announces 2025 Presidential Citations
One of the privileges of being president of the American Nuclear Society is awarding Presidential Citations to individuals who have demonstrated outstanding effort in some manner for the benefit of ANS or the nuclear community at large. Citations are conferred twice each year, at the Annual and Winter Meetings.
ANS President Lisa Marshall has named this season’s recipients, who will receive recognition at the upcoming Annual Conference in Chicago during the Special Session on Tuesday, June 17.
William D. Fullmer, Martin A. Lopez De Bertodano
Nuclear Technology | Volume 191 | Number 2 | August 2015 | Pages 185-192
Technical Note | Fission Reactors | doi.org/10.13182/NT14-110
Articles are hosted by Taylor and Francis Online.
One-dimensional two-fluid models used for the simulation of large, industrial-scale problems require many simplifying assumptions to make a closed model that is tractable, applicable to a wide variety of flow regimes, and computationally efficient. Of particular interest here is the virtual mass force and the simplified form used in the RELAP5/MOD3.3 model. Comparison of the characteristics of the simplified model with a more complete two-fluid model for bubbly two-phase flow shows a remarkable similarity. Comparison to experimental data is also surprisingly favorable—provided that the flow conditions are determined appropriately. Namely, the characteristic analysis determined that a drift velocity for distorted bubbly flow, rather than for churn-turbulent flow, matches the data more accurately. The study is concluded by implementing a distorted bubbly drift velocity correlation into the RELAP5/MOD3.3 code. A comparison of the void wave speeds with the data confirms the results of the characteristic analysis.