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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Hash Hashemian: Visionary leadership
As Dr. Hashem M. “Hash” Hashemian prepares to step into his term as President of the American Nuclear Society, he is clear that he wants to make the most of this unique moment.
A groundswell in public approval of nuclear is finding a home in growing governmental support that is backed by a tailwind of technological innovation. “Now is a good time to be in nuclear,” Hashemian said, as he explained the criticality of this moment and what he hoped to accomplish as president.
Emilian Popov, Boyan Ivanov, Kostadin N. Ivanov, Stilyana Mladenova
Nuclear Technology | Volume 158 | Number 3 | June 2007 | Pages 358-365
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT07-A3847
Articles are hosted by Taylor and Francis Online.
Flow rotation and mixing in a VVER-1000 reactor is investigated using two system codes with three-dimensional fluid-dynamics modeling capabilities (RELAP5-3D and TRACE) and a computational fluid-dynamics (CFD) code (FLUENT). Coarse-mesh models were developed for the system codes, and their applicability is evaluated using the test data as well as the detailed CFD results obtained. Two different temperature zone mapping schemes for comparison with the measured data are proposed and discussed.The test is very informative when used to examine the real loop mixing taking place at a nuclear reactor. The results can be used to improve code input data for correct simulation of the phenomenon. Correctly predicting the flow mixing is very important in regard to the prediction of the local three-dimensional feedback effects depending on the vessel mixing in coupled three-dimensional neutron-kinetic/thermal-hydraulic safety analysis of reactivity insertion accidents such as the main steam line break accident.