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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.
Chien-Hsiung Lee, I-Ming Huang, Chin-Jang Chang, Tay-Jian Liu, Yuh-Ming Ferng
Nuclear Technology | Volume 126 | Number 1 | April 1999 | Pages 48-61
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT99-A2957
Articles are hosted by Taylor and Francis Online.
The RELAP5/MOD3.2 code is used at the Institute of Nuclear Energy Research Integral System Test Facility to analyze a 2% cold-leg-break experiment that includes failure of the high-pressure injection system. The assessment code predictions include primary pressure, inventory distribution in the reactor coolant system (RCS), loop flow rate, break flow rate, and core thermal hydraulics. A comparison between the calculated results and the experimental data shows (a) a good match with the predictions of the RCS pressure and hot- and cold-leg fluid temperatures, (b) underprediction of the core and downcomer levels, (c) overprediction of the loop flow rates in single- and two-phase natural circulation, and (d) inadequate prediction of asymmetric coolant holdup in the three steam generators. Also presented are sensitivity studies of choked flow associated with the defaulted values of discharge coefficients in the simulation of the break flow, and of the core bypass area to evaluate the effect of core level depression.