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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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.
P. Pohl , M. Wimmers, T. Kindt, W. Feltes, U. Schmid, H. Jung
Nuclear Science and Engineering | Volume 97 | Number 1 | September 1987 | Pages 64-71
Technical Paper | doi.org/10.13182/NSE87-A23497
Articles are hosted by Taylor and Francis Online.
The measurements that were made in recent years to determine the hot and the cold coefficient of reactivity and the corresponding model calculations carried out by both Interatom and Hochtemperaturreaktorbau are described. The effects of the partial load of low-enriched uranium (LEU) fuel were of major interest. The cold coefficient is determined in shutdown periods by measuring the subcriticality at different core temperatures. The hot coefficient is determined under operation in connection with a change in coolant outlet temperature at constant power using a calibrated rod curve. In the case of the cold coefficient, experiment and model calculations are in perfect agreement. Calculated values for the hot coefficient are ∼20% lower than the experimental ones. However, neither experiment nor model calculation show any significant change of the hot coefficient when about one-fourth of the core content was being replaced by LEU fuel.