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Ward250 reactor rides cargo to Utah
Valar Atomics’ Ward250 microreactor is loaded onto the aircraft.
A public-private partnership between the Departments of Defense and Energy and Valar Atomics marked a milestone over the weekend when Valar’s Ward250 microreactor was transported (without fuel) from California to Utah using three C-17 aircraft. The reactor will now trek from Hill Air Force Base to the Utah San Rafael Energy Lab (URSEL) for testing and evaluation.
Peter Yarsky
Nuclear Technology | Volume 207 | Number 5 | May 2021 | Pages 653-664
Technical Paper | doi.org/10.1080/00295450.2020.1800308
Articles are hosted by Taylor and Francis Online.
The U.S. Nuclear Regulatory Commission (NRC) staff often performs confirmatory analysis to support regulatory decision making. In the current work the TRAC/RELAP Advanced Computational Engine (TRACE) code was used to study the transient system response for the NuScale power module to a beyond-design-basis event where the control rods fail to insert. The regulatory purpose of the current work was to confirm the results of analyses provided by the applicant as part of their probabilistic risk assessment analysis that demonstrates that the core is not damaged under certain conditions when the control rods fail to insert. The NRC staff performed calculations using a TRACE model of the NuScale power module that includes both the primary and secondary systems that simulates a loss of alternating-current power and complete failure of the module protection system to insert control rods. The NRC staff analyses demonstrate that under these conditions the reactor stabilizes at a new stable condition with minor power and pressure oscillations where core power is balanced by passive heat removal.