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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.
T. Trombetti, D. L. Hetrick
Nuclear Science and Engineering | Volume 86 | Number 2 | February 1984 | Pages 129-135
Technical Paper | doi.org/10.13182/NSE84-A18195
Articles are hosted by Taylor and Francis Online.
A multinode treatment of the problem of nonlinear reactor stability is given. The nodal kinetics equations account for nodal powers, precursor concentrations, and temperatures. Nonlinear power-plus-temperature feedbacks are admitted in each node. Quadratic and logarithmic Lyapunov functions are considered. By formulating and solving a suitable nonlinear programming problem, the optimal estimate of the domain of attraction of the reactor-operating equilibrium state that can be afforded by the aforesaid V functions is explicitly constructed. An example of a reactor with two nodal power feedbacks (one destabilizing) and two destabilizing nodal temperature feedbacks is given. These feedbacks are seen to give rise to an unstable equilibrium reactor state, in the region of all-positive perturbations, which is extremely well approached by the boundary of the estimate of the domain of attraction.
