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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 L. Popov, Graydon L. Yoder, Valeri Velichkov
Nuclear Technology | Volume 149 | Number 3 | March 2005 | Pages 304-308
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT05-A3597
Articles are hosted by Taylor and Francis Online.
Detailed thermal-hydraulic analysis of commercial power reactors requires modeling of complex multidimensional thermal, fluids, and neutronic behavior. One code that has three-dimensional (3-D) thermal-hydraulic and neutronic capabilities is RELAP-3D. A comparison of RELAP-3D predictions to experimental data obtained during start-up of the Kozloduy VVER-1000 nuclear power plant in Bulgaria is presented here. The experiment has distinguishable 3-D hydraulics effects that allow for code model verification and reasonable agreement with the experimental results obtained.The transient investigated was conducted at 29% reactor power, and it was initiated from a steady state where three out of four reactor coolant pumps were operating. The transient consisted of the start-up of the nonoperating pump. Simulation results were compared to both temperature and pump data from the experiment. Temperature predictions compared reasonably well to the experimental data; however, discrepancies existed between predicted and experimental pump head values.