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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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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.
Chaung Lin,Lawrence M. Grossman
Nuclear Science and Engineering | Volume 92 | Number 4 | April 1986 | Pages 531-544
Technical Paper | doi.org/10.13182/NSE86-A18610
Articles are hosted by Taylor and Francis Online.
A multilevel method is applied to the load-following control of a boiling water reactor using a nodal reactor model with practical operational constraints and thermal limits. Due to the very large size of the problem, a decomposition is made using hierarchical control techniques. The optimization of the resulting subproblems is performed using the feasible direction method. An objective functional, of quadratic form, is defined to reflect the control objective, namely, to achieve the desired thermal power (tracking) with minimum effort, returning to the initial xenon and iodine concentration as closely as possible. Nodal source equation and discretized Xe-I dynamic equations are formulated as equality constraints, while the linear heat generation rate and the rate of power increase are formulated as inequality constraints. Core flow and control rod position are the control variables. A simplified model of the core is used, with 4×4 fuel assemblies that have one control rod at the center.