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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.
Gyoo Won Suh and Hee Cheon No
Nuclear Science and Engineering | Volume 90 | Number 3 | July 1985 | Pages 236-247
Technical Paper | doi.org/10.13182/NSE85-A17765
Articles are hosted by Taylor and Francis Online.
The USODA (U-tube Steam Generator Controller Design Analysis) code was developed to simulate the transient behavior of a vertical natural circulation U-tube steam generator in pressurized water reactors and to design the optimal level controller. The steam generator was represented by sixth order linear differential equations through matrix reduction. The momentum equation for the recirculation flow models the effects of the separators, U-bend regions, and spatial acceleration. To assure stability, the Lyapunov theorem was adopted. The optimal gains were obtained by minimizing the quadratic performance index and by using both Newton-Raphson and successive overrelaxation methods, which guarantee fast convergence. Sample calculations for Korea Nuclear Unit 2 showed that a control system consisting of standard proportional integral differential controls can be successfully employed for the control of water level. The optimization procedure led to a stable system with good controlled response.