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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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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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Empowering the next generation: ANS’s newest book focuses on careers in nuclear energy
A new career guide for the nuclear energy industry is now available: The Nuclear Empowered Workforce by Earnestine Johnson. Drawing on more than 30 years of experience across 16 nuclear facilities, Johnson offers a practical, insightful look into some of the many career paths available in commercial nuclear power. To mark the release, Johnson sat down with Nuclear News for a wide-ranging conversation about her career, her motivation for writing the book, and her advice for the next generation of nuclear professionals.
When Johnson began her career at engineering services company Stone & Webster, she entered a field still reeling from the effects of the Three Mile Island incident in 1979, nearly 15 years earlier. Her hiring cohort was the first group of new engineering graduates the company had brought on since TMI, a reflection of the industry-wide pause in nuclear construction. Her first long-term assignment—at the Millstone site in Waterford, Conn., helping resolve design issues stemming from TMI—marked the beginning of a long and varied career that spanned positions across the country.
Y. S. Na, W. Lee, S. Song
Nuclear Technology | Volume 206 | Number 4 | April 2020 | Pages 544-553
Technical Paper | doi.org/10.1080/00295450.2019.1657328
Articles are hosted by Taylor and Francis Online.
This study observed the breakup of helium stratification, which was 30 vol % helium in air and formed in the upper part of a cylindrical test vessel with a height of 9.5 m and a diameter of 3.4 m. An air jet collided with the density interface on which the restoring buoyancy of the helium and the disturbing inertial force of the impinging jet were balanced. The Reynolds number of the jet was about 20 000 at the exit of a vertical pipe located 3.0 m below the initial stratification. The helium concentration was measured by sampling the gas mixture with thermal conductivity analyzers. Particle image velocimetry (PIV) visualized the flow field of the jet impinging on the density interface. The density interface was clearly shown by the binary images generated from the number of tracer particles for the PIV. From the continuous impinging jet, the density interface gradually moved upward. The interaction Froude number, which was defined by the ratio of the inertial force of the impinging jet to the buoyancy of a light gas on the density interface, was about unity calculated by the helium concentration and the flow visualization. The density interface went up to 0.0002 m/s.
