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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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Latest News
NNSA awards BWXT $1.5B defense fuels contract
The Department of Energy’s National Nuclear Security Administration has awarded BWX Technologies a contract valued at $1.5 billion to build a Domestic Uranium Enrichment Centrifuge Experiment (DUECE) pilot plant in Tennessee in support of the administration’s efforts to build out a domestic supply of unobligated enriched uranium for defense-related nuclear fuel.
David L. Chapin, William G. Price, Jr.
Nuclear Technology | Volume 31 | Number 1 | October 1976 | Pages 32-47
Technical Paper | Reactor | doi.org/10.13182/NT76-A31696
Articles are hosted by Taylor and Francis Online.
Since the tokamak scheme of plasma confinement provides a toroidal source of fusion neutrons,wide variations in the source distribution at the wall surface are possible. A numerical solution of the neutron streaming equation has been applied to the calculation of the flux and current as functions of wall position for a circular crosssection tokamak and two noncircular tokamaks, the Princeton Reference Design (PRD) and the University of Wisconsin UWMAK-I. The results show significant variations in the pattern of the angular flux and substantial peaking in the scalar flux and current. For example, the current peaks at 22% above nominal for the circular case, 43% for the PRD, and 12% for UWMAK-I. The nominal value, total source ÷ total area, is the commonly stated “wall load.” Effects of this magnitude cannot be ignored in future reactor designs when power densities, damage rates, etc., are evaluated.