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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
Standards Program
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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Powering the future: How the DOE is fueling nuclear fuel cycle research and development
As global interest in nuclear energy surges, the United States must remain at the forefront of research and development to ensure national energy security, advance nuclear technologies, and promote international cooperation on safety and nonproliferation. A crucial step in achieving this is analyzing how funding and resources are allocated to better understand how to direct future research and development. The Department of Energy has spearheaded this effort by funding hundreds of research projects across the country through the Nuclear Energy University Program (NEUP). This initiative has empowered dozens of universities to collaborate toward a nuclear-friendly future.
A. L. Wight, P. Girouard
Nuclear Science and Engineering | Volume 68 | Number 1 | October 1978 | Pages 61-72
Technical Paper | doi.org/10.13182/NSE78-A27271
Articles are hosted by Taylor and Francis Online.
The Canadian Deuterium-Uranium (CANDU) pressurized heavy water reactor is fueled continuously at power, with alternate channels being fueled in opposite directions (continuous bidirectional fueling). The rate at which channels are refueled in various regions of the core determines the burnup distribution in the core. The burnup distribution in the core determines the power distribution. In present practice, the core is divided radially into two burnup regions having constant average discharge burnup. The limit on maximum neutron flux and the requirement for a critical system determine the size of the inner burnup region and the values of the burnups in the two regions. We can increase the core average exit burnup if we allow the burnup distribution to vary continuously rather than being regionwise constant. The purpose of this analysis is to derive an optimum burnup distribution that will maximize core average discharge burnup subject to a limit on maximum flux. This is equivalent to minimizing the total fuel feed rate. A set of equations describing the optimum distribution of burnup has been derived using calculus of variations techniques. These equations have been solved numerically in one-dimensional cylindrical geometry for homogeneous cores of approximately the size of current generation CANDU reactors.