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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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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New coolants, new fuels: A new generation of university reactors
Here’s an easy way to make aging U.S. power reactors look relatively youthful: Compare them (average age: 43) with the nation’s university research reactors. The 25 operating today have been licensed for an average of about 58 years.
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.