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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.
Alessandro Annunziato
Nuclear Technology | Volume 96 | Number 2 | November 1991 | Pages 215-228
Technical Paper | Heat Transfer and Fluid Flow | doi.org/10.13182/NT91-A34607
Articles are hosted by Taylor and Francis Online.
Referring to single-phase natural circulation in steam generators with inverted U-tubes, various working conditions can be postulated in response to perturbations in the operating parameters. Clearly, such behavior is related to potential flow instabilities in parallel channels connected to a common manifold. A physical and analytical interpretation is given of the mechanism governing the onset and eventual divergence of flow surges observed in the LOBI-MOD2 steam generators during the evolution of thermal-hydraulic transients relevant to decay heat removal in pressurized water reactors. Secondary-side heat sink degradation is identified as the primary mechanism leading to the observed oscillations. A generalized analytical steady-state model is used to identify potential unstable operating conditions in the steam generators; a numerical method is then used to describe the transient condition.