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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.
Ola Thomson, Ninos S. Garis,†, Imre Pázsit
Nuclear Technology | Volume 120 | Number 1 | October 1997 | Pages 71-80
Technical Paper | Reactor Operation | doi.org/10.13182/NT97-A35432
Articles are hosted by Taylor and Francis Online.
Detecting the vibration and impacting of neutron detectors in boiling water reactor cores is usually attempted from the detector signals. Two such indicators used or suggested earlier are the widening of the vibration peak in the detector noise auto-power spectral density and the deviation from Gaussian ( = “distortion”) of the signal amplitude probability distribution (APD). Quantification of both methods is hindered by the presence of a strong, Gaussian background; thus, it was thought that band-pass filtering around the vibration peak would improve the performance of the methods. This suggestion has been investigated. It turns out that filtering reduces the background, but it also distorts the vibration component of the signal. For good performance, this latter effect must be compensated for. Such methods are elaborated and applied to both peak widening and APD distortion techniques. It was found that application of such techniques makes the kurtosis and the decay ratio associated with the signal suitable to be used as quantitative indicators of impacting. The methods elaborated were also checked by numerical simulations and real measurements with positive results.