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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.
Mark J. Holowach, Lawrence E. Hochreiter, Fan-Bill Cheung, David L. Aumiller
Nuclear Technology | Volume 140 | Number 1 | October 2002 | Pages 18-27
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT02-A3320
Articles are hosted by Taylor and Francis Online.
Critical heat flux (CHF) at a low-flow condition in a small-hydraulic-diameter duct is an important phenomenon for a Materials Test Reactor/Advanced Test Reactor (MTR/ATR) design under a number of accident conditions, including reflood transients. Current CHF models in the literature, such as the Mishima/Nishihara and Oh/Englert CHF models, are based on macroscopic system parameters and not local thermal-hydraulic conditions. These macroscopic parameter-based models cannot be readily used for analysis in transient best-estimate thermal-hydraulic codes. The present work focuses on developing a low-flow-rate CHF correlation, based on local conditions, that is amenable to implementation into a best-estimate transient thermal-hydraulic code for a small-hydraulic-diameter duct. The model development proceeds with a means of correlating CHF data to local conditions parameters and then applying a correction factor to the resulting correlation, subsequently permitting accurate predictions over a range of pressures. An evaluation of the proposed local conditions-based CHF model is conducted by predicting independent sets of CHF experimental results over a range of flow rate, pressure, and subcooling conditions. Conclusions on the viability of the proposed CHF model and suggestions for future efforts in improving the reflood heat transfer CHF models for small-hydraulic-diameter ducts are provided with an evaluation of the model results.