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2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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Latest News
NNSA awards BWXT $1.5B defense fuels contract
The Department of Energy’s National Nuclear Security Administration has awarded BWX Technologies a contract valued at $1.5 billion to build a Domestic Uranium Enrichment Centrifuge Experiment (DUECE) pilot plant in Tennessee in support of the administration’s efforts to build out a domestic supply of unobligated enriched uranium for defense-related nuclear fuel.
Tyler Sumner, Tingzhou Fei
Nuclear Science and Engineering | Volume 196 | Number 1 | October 2022 | Pages S309-S322
Technical Paper | doi.org/10.1080/00295639.2021.2009982
Articles are hosted by Taylor and Francis Online.
The Versatile Test Reactor (VTR) is a fast spectrum test reactor currently being developed in the United States under the direction of the U.S. Department of Energy, Office of Nuclear Energy. Safety analysis of the conceptual VTR design is being performed using the SAS4A/SASSYS-1 fast reactor safety analysis code with a model representing the reactor core, primary and intermediate heat transport systems, reactor vessel auxiliary cooling system, and reactor protection system. The system’s response and safety performance has been evaluated for a wide spectrum of event initiators and accident sequences. This paper focuses on the results for several unprotected transient scenarios where the reactor protection system is assumed to fail to take any action. Even without the reactor protection system, the strong reactivity feedback response of the core reduces power to safe levels matching the available heat rejection. In the station blackout transient, the primary heat transport system is able to transition quickly and effectively to natural circulation. At the current stage of design, transient simulation results for the VTR indicate that large safety margins exist for many event initiators, including the unprotected transients presented in this paper.