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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.
Lance L. Snead, Roger A. Vesey†
Fusion Science and Technology | Volume 24 | Number 1 | August 1993 | Pages 83-96
Technical Paper | Divertor System | doi.org/10.13182/FST93-A30176
Articles are hosted by Taylor and Francis Online.
The primary concerns in the design of a divertor component are the high heat fluxes (15 to 30 MW/m2) and the surface erosion due to plasma/wall interactions, along with the associated issue of plasma contamination. A continuous belt, which would pass between two rollers inside the vacuum vessel, is proposed as the divertor surface to provide higher heat flux handling capability as well as reduced total erosion. Thermal analyses indicate that a belt passing from one roller through the divertor region to a cooling roller can achieve a cycle-to-cycle steady state while maintaining acceptable temperatures. The belt speed determines the amount of plasma energy absorbed per cycle and thus determines the maximum belt temperature and the requirements of the cooling roller. The belt material initially considered is a metal matrix/carbon fiber composite in which the carbon fibers are oriented out-of-plane in a 1-mm-thick metal belt. The carbon fibers protrude from the plasma-facing side of the belt, presenting the plasma ions a low-Z surface to impact. Because the belt surf ace passes through the entire divertor region, the erosion due to sputtering is uniform along the belt. Estimated gross erosion rates for a 7-m belt at expected International Thermonuclear Experimental Reactor (ITER) conditions are 5 to 10 cm/burn-yr. Electromagnetic forces and secondary magnetic fields induced by the belt motion appear manageable for a sufficiently resistive or toroidally segmented belt. In situ deposition of a sacrificial carbon layer will be required to replace eroded material. Such a belt also offers the possibility of continuous removal of the plasma-codeposited carbon and tritium layer prior to deposition of the sacrificial carbon.