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2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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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.
Mohamed S. El-Genk, Huimin Xue, Dmitry Paramonov
Nuclear Technology | Volume 105 | Number 1 | January 1994 | Pages 70-86
Technical Paper | Special on Nuclear Criticality Safety / Nuclear Reactor Safety | doi.org/10.13182/NT94-A34912
Articles are hosted by Taylor and Francis Online.
The thermionic transient analysis model is used to simulate the startup of the TOPAZ-II space nuclear power system in orbit. The simulated startup procedures are assumed for the purpose of demonstrating the capabilities of the model and may not represent an accurate account of the actual startup procedures of the TOPAZ-II system. The temperature reactivity feedback effects of the moderator, UO2 fuel, electrodes, coolant, and other components in the core are calculated, and their effects on the thermal and criticality conditions of the reactor are investigated. Also, estimates of the time constants of the temperature reactivity feedback for the UO2fuel and the ZrH moderator during startup, as well as of the total temperature reactivity feedback as a function of the reactor steady-state thermal power, are obtained.
