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The busyness of the nuclear fuel supply chain
Ken Petersenpresident@ans.org
With all that is happening in the industry these days, the nuclear fuel supply chain is still a hot topic. The Russian assault in Ukraine continues to upend the “where” and “how” of attaining nuclear fuel—and it has also motivated U.S. legislators to act.
Two years into the Russian war with Ukraine, things are different. The Inflation Reduction Act was passed in 2022, authorizing $700 million in funding to support production of high-assay low-enriched uranium in the United States. Meanwhile, the Department of Energy this January issued a $500 million request for proposals to stimulate new HALEU production. The Emergency National Security Supplemental Appropriations Act of 2024 includes $2.7 billion in funding for new uranium enrichment production. This funding was diverted from the Civil Nuclear Credits program and will only be released if there is a ban on importing Russian uranium into the United States—which could happen by the time this column is published, as legislation that bans Russian uranium has passed the House as of this writing and is headed for the Senate. Also being considered is legislation that would sanction Russian uranium. Alternatively, the Biden-Harris administration may choose to ban Russian uranium without legislation in order to obtain access to the $2.7 billion in funding.
Yousef M. Farawila, Douglas W. Pruitt
Nuclear Science and Engineering | Volume 154 | Number 3 | November 2006 | Pages 302-315
Technical Paper | doi.org/10.13182/NSE06-A2635
Articles are hosted by Taylor and Francis Online.
A study of the nonlinear behavior of growing density-wave oscillations is presented in the framework of a reduced-order model. Nonlinear effects are included in both the hydraulic and neutron kinetics equations, where both were found to contribute to the observed limit cycles. In this paper, Part I, the basic concepts were developed and applied to the global oscillation mode, where only the fundamental neutron flux mode excitation is considered. Approximate analytical solutions for the limit cycle amplitude and the time evolution of the transient were derived. In Part II, the model order is increased to allow the representation of the azimuthal neutron flux harmonic and the simulation of growing regional mode oscillations. Analysis demonstrates that the regional mode, unlike the global mode, may not always reach a stable limit cycle, and if it does, the regional limit cycle amplitudes are large compared with the global mode. An extended reduced-order model has been developed for use as an accurate quantitative tool for simulating actual reactor situations, whereas the current paradigm restricts the applicability of reduced-order models to gaining qualitative insights.