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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Fermi America looks to go public as NRC accepts COLA for AP1000s
Texas Tech University and Fermi America are now one step closer to realizing their massive vision for the Advanced Energy and Intelligence Campus in Amarillo, Texas, as the Nuclear Regulatory Commission has accepted the first two parts of its combined license application (COLA) for four Westinghouse AP1000s.
R. G. Gonzalez, F. D'Auria, O. Mazzantini
Nuclear Technology | Volume 194 | Number 1 | April 2016 | Pages 61-72
Technical Paper | doi.org/10.13182/NT14-155
Articles are hosted by Taylor and Francis Online.
Atucha-2 is a Siemens-designed pressurized heavy water reactor located in Argentina. Its geometrical complexity and peculiarity [e.g., oblique control rods (CRs) and positive void coefficient] required a developed and validated complex three-dimensional (3-D) neutron kinetics (NK) model. In the framework of the agreement between NA-SA (Nucleo-electrica Argentina Sociedad Anonima) and the University of Pisa, a detailed NESTLE (3-D NK code) model of the Atucha-2 nuclear power plant (NPP) was developed. This document summarizes the procedures for implementing oblique CRs into the RELAP5/NESTLE model: A particular arrangement of the RELAP5/NESTLE CR insertion mode for oblique CRs and an implementation into the homogenized two-group cross sections of ad hoc calculated correction factors (these parameters were obtained by previously executed Monte Carlo calculations) were developed. Some applications, among the scenarios selected to perform safety analysis (Final Safety Analysis Report) of the Atucha-2 NPP (CNA-II), are also reported: preliminary scram rod worth, analysis of a CR ejection accident, and a CR faulty withdrawal.