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Young Members Group
The Young Members Group works to encourage and enable all young professional members to be actively involved in the efforts and endeavors of the Society at all levels (Professional Divisions, ANS Governance, Local Sections, etc.) as they transition from the role of a student to the role of a professional. It sponsors non-technical workshops and meetings that provide professional development and networking opportunities for young professionals, collaborates with other Divisions and Groups in developing technical and non-technical content for topical and national meetings, encourages its members to participate in the activities of the Groups and Divisions that are closely related to their professional interests as well as in their local sections, introduces young members to the rules and governance structure of the Society, and nominates young professionals for awards and leadership opportunities available to members.
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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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.
Aaron M. Thomas, Jun Fang, Jinyong Feng, Igor A. Bolotnov
Nuclear Technology | Volume 190 | Number 3 | June 2015 | Pages 274-291
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT14-72
Articles are hosted by Taylor and Francis Online.
The goal of the present study is to demonstrate that direct numerical simulations (DNS) coupled with interface tracking methods can be used to estimate interfacial forces in two-phase flows. Current computational multiphase fluid dynamics codes model interfacial forces utilizing closure laws that are heavily dependent on limited experimental data and simplified analytical approximations. In the present work, a method for improving the current interfacial force database has been developed by using DNS to quantify the lift and drag forces on a single bubble in laminar and turbulent shear flows. A proportional-integral-derivative–based controller was implemented into the finite element–based, multiphase flow solver [PHASTA (Parallel, Hierarchic, higher-order accurate, Adaptive, Stabilized, finite element method Transient Analysis)] to control the bubble position. This capability allowed for utilization of a steady-state force balance on the bubble to determine lift and drag coefficients in various shear flows. Specifically, for low shear flows (2.0 s−1), the effect of the wall presence is analyzed, and for high shear flows, the effect of turbulence is studied. A number of uniform shear (10.0 to 470.0 s−1) laminar flows were simulated to assess lift and drag force behavior as the kinetic energy of the flow increased. Two high shear (236.0 and 470.0 s−1) turbulent flows were simulated to understand bubble-turbulence interaction influence on the drag and lift phenomena. Two uniform shear rates (20.0 and 100 s−1) were simulated utilizing pressurized water reactor fluid properties. The lift and drag coefficients estimated in this work are in agreement with models developed for low shear laminar flows, whereas for high shear laminar and turbulent flows, bubble-turbulence interaction became a dominating influence in the lift and drag coefficient estimation. The novel results and method presented in this paper offer a path to simulating full-fledged reactor coolant environments where the lift and drag forces on a single bubble can be studied.
