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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.
Young Jin Kim,* Thomas J. Downar, Alexander Sesonske
Nuclear Science and Engineering | Volume 96 | Number 2 | June 1987 | Pages 85-101
Technical Paper | doi.org/10.13182/NSE87-A16369
Articles are hosted by Taylor and Francis Online.
A method was developed to optimize pressurized water reactor low-leakage core reload designs that features the decoupling and sequential optimization of the fuel arrangement and control problems. The two-stage optimization process provides the maximum cycle length for a given fresh fuel loading subject to power peaking constraints. In the first stage, a best fuel arrangement is determined at the end of cycle (EOC) in the absence of all control poisons by employing a direct search method. The constant power, Haling depletion is used to provide the cycle length and EOC power peaking for each candidate core fuel arrangement. In the second stage, the core control poison requirements to meet the core peaking constraints throughout the cycle are determined using an approximate nonlinear programming technique. For the core description, the design method utilizes a currently recognized licensing-type code, SIMULATE-E, that was adapted to the CYBER-205 computer. The methodology was applied to the core reload design for cycles 9 and 10 of the Commonwealth Edison Company (CECo) Zion-1 reactor. The results showed that, compared with the reference design used by CECo, the optimum loading pattern for cycle 9 yielded almost a 9% increase in the cycle length while reducing core vessel fluence by 30%. Cycle length increase is a direct measure of economic savings for a given fuel loading. The results of cycle 10 optimization produced similar improvements. Should cycle length constraints apply, the procedure could be used to yield a decrease in fuel enrichment, with comparable savings resulting.