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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.
Yassin A. Hassan, Hagop R. Barsamian
Nuclear Technology | Volume 128 | Number 1 | October 1999 | Pages 58-74
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT99-A3014
Articles are hosted by Taylor and Francis Online.
The dynamic subgrid-scale (DSGS) closure model is used in a large eddy simulation computer program for incompressible isothermal flows. One of the advantages of the DSGS model is the exclusion of a model coefficient. This model coefficient is evaluated dynamically at each nodal location for a given time step by filtering operations on the grid level and a test filter level. A nonstaggered array tube bundle geometry arrangement is considered in doubly periodic boundary conditions for two-dimensional simulations at high Reynolds number. Results of the DSGS simulation are obtained in the form of power spectral densities and visualization of flow characteristics. The DSGS model simulation results are compared to the Smagorinsky eddy viscosity model simulation and available experimental data. The DSGS model simulation is found to be in good agreement with spectral data available from experiments in similar bundle arrangements. Coherent eddy structures were observed. Body forces acting on the tubes showed satisfactory characteristics. Integral length and timescales are evaluated using correlation functions that describe the turbulence structure. The applicability of large eddy simulation to complex engineering flow situations has been shown using the DSGS model with applications to steam generator bundles for understanding of flow-induced vibration problems revealing the physical phenomena of the flow.