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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.
Piyush Sabharwall, Vivek Utgikar, Fred Gunnerson
Nuclear Technology | Volume 166 | Number 2 | May 2009 | Pages 197-200
Technical Note | Thermal Hydraulics | doi.org/10.13182/NT09-A7406
Articles are hosted by Taylor and Francis Online.
The effect of the mass flow rate at constant velocity on the convective heat transfer coefficient of an incompressible fluid in a turbulent flow regime is presented with the help of dimensional analysis. The heat transfer coefficient decreases by ~10% with a threefold increase in the mass flow rate under these conditions, based on the commonly used Dittus-Boelter correlation for estimation of the heat transfer coefficient. On the other hand, an increase in the heat transfer coefficient is observed if the area is maintained constant. Doubling the mass flow rate will result in a 92% increase in the heat transfer coefficient. However, there is a concomitant increase in the pressure drop, proportional to the mass flow rate raised to 0.95. The pressure drop is predicted to decrease for the constant velocity case with an inverse dependence on the mass flow rate. The pressure drop considerations may be critical in certain situations (elevation of boiling point in case of a boiling heat transfer medium), and any benefit derived from the higher heat transfer coefficient may be lost because of the higher pressure drop across the heat exchanger in the constant area case.