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NRC approves TerraPower construction permit
Today, the Nuclear Regulatory Commission announced that it has approved TerraPower’s construction permit application for Kemmerer Unit 1, the company’s first deployment of Natrium, its flagship sodium fast reactor.
This approval is a significant milestone on three fronts. For TerraPower, it represents another step forward in demonstrating its technology. For the Department of Energy, it reflects progress (despite delays) for the Advanced Reactor Demonstration Program (ARDP). For the NRC, it is the first approval granted to a commercial reactor in nearly a decade—and the first approval of a commercial non–light water reactor in more than 40 years.
Yong Jin Cho, Gyoo Dong Jeun
Nuclear Technology | Volume 158 | Number 3 | June 2007 | Pages 366-377
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT07-A3848
Articles are hosted by Taylor and Francis Online.
The header of a Canada deuterium uranium reactor (CANDU) is an important component in simulating the fuel channel behavior because the header's hydraulic behavior controls the feeder void fraction, which affects the fuel bundle coolability. In CANDU accident analyses, the liquid entrainment and vapor pull-through (off-take) phenomena should be considered when horizontal stratification is achieved inside the header. The current RELAP5 off-take model can treat only three directions: vertical upward, vertical downward, and side oriented junctions. In this study, the RELAP5 off-take model was modified and generalized by considering the geometric effect of branch angles. Based on Craya's approach, the critical height correlation was reconstructed by use of the branch line connection angle. The new model in RELAP5/CANDU could be applied to vertical upward, vertical downward, and angled branch. The verification and validation analyses for this new model were performed using separate effect test and integral effect test results. The verification and validation analyses show improved accuracy with the new model.