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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.
Kevin T. Clarno, Yassin A. Hassan
Nuclear Technology | Volume 141 | Number 2 | February 2003 | Pages 142-156
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT03-A3356
Articles are hosted by Taylor and Francis Online.
In order to analyze the benefits of the multidimensional hydrodynamic modeling capability of the RELAP5-3D system code for the VVER-1000 nuclear power plant (NPP), a three-dimensional (3-D) model of the core, downcomer, and lower plenum has been created to replace the NPP one-dimensional (1-D) counterparts in a complete plant model. This multidimensional model has been validated with plant operational data and other computer simulations of a thermal-hydraulic transient. The simulated transient considered was a large-break loss-of-coolant accident (LB LOCA).A validated, 1-D control model of the NPP, for the study of the effects of mixed oxide fuel, was modified to include a standard fuel loading of UO2. The development of the 3-D sections of the reactor vessel consisted of ensuring geometrical fidelity with the design of the modeled plant, the Balakovo Unit 4 NPP in Saratov, Russia. A stable operational steady state was obtained and the calculated plant conditions compared well with the design values of the Balakovo plant. Transient results verified that the simulated thermal-hydraulic conditions of the multidimensional model agreed well with both the control and analyses that have been performed separately from this study.It was found that the multidimensional model has shown a reduction in the calculated hot-spot peak-clad temperature (PCT) during the blowdown stage of a LB LOCA and an increase in PCT during the reflood stage. A preliminary uncertainty analysis of the PCT during blowdown stage was performed using a response surface method of the Code Scaling, Applicability, and Uncertainty Method and a significant number of relevant input variables. From the preliminary analysis, the PCT reduction during blowdown appears to be significant, but a further, more detailed analysis should be performed, along with an uncertainty analysis of the PCT during the reflood stage.The enhanced depiction of the flow patterns and temperature distributions in the transient situation allowed the user further understanding of the thermal-hydraulic conditions throughout the transient. The developed model proved to be suitable for analysis of the VVER-1000 plant, but to further the applicability of the model, a 3-D kinetics model of the neutronics and 3-D hydrodynamic models of the horizontal steam generators should be included.
