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2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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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.
Jan Bartak, Timo Haapalehto
Nuclear Technology | Volume 106 | Number 1 | April 1994 | Pages 46-59
Technical Paper | Nuclear Reactor Safety | doi.org/10.13182/NT94-A34949
Articles are hosted by Taylor and Francis Online.
A top-down reflooding model was developed and implemented into the French best-estimate thermalhydraulic code CATHARE2 V1.3E. A two-dimensional mesh moving along the wall with the quench front is used to resolve the heat conduction equation in the wall near the quench front. The results of the model validation and the first assessment calculations are given. The Winfrith single-tube top-down reflooding experiments were used to validate the model. The influence of wall material, pressure, mass flux, and wall temperature on the quench front velocity are correctly predicted. The REWET-II and PERICLES experiments in rod bundle geometry were used to assess the capabilities of the code to predict simultaneous bottom and topdown rewetting. Comparison of the calculated results with the RE WET II experimental data shows the ability of the new package to calculate the key features of this complex experiment. The existence and progression of two quench fronts in the core are correctly predicted. The maximum cladding temperatures are overpredicted for experiments with combined and upper plenum injection. This difference, which is attributed to a too severe countercurrent flow limit (CCFL) calculated by the code, does not exceed 150°C. With the top-down reflooding option, improved predictions of wall temperatures in the upper part of the core in the PERICLES tests with respect to the previous version of the code were obtained, since this part of the core was rewetted by top-down quenching. To realize further improvements in combined reflooding calculations, the CCFL predicting capabilities of CATHARE should be addressed first. More detailed experimental information and additional data would also be required for in-depth assessment of the models.