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Conference Spotlight
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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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.
Jun-Yun Yang, Xiao Gang, Yang-Jun Ying
Nuclear Science and Engineering | Volume 182 | Number 4 | April 2016 | Pages 538-554
Technical Paper | doi.org/10.13182/NSE15-44
Articles are hosted by Taylor and Francis Online.
A code called CriSAA used for criticality excursion evaluation and analysis is developed by coupling a two-dimensional thermal-hydraulic code and a zero-dimensional neutron kinetics code. The generalized semi-Markov process simulation method is improved in the neutron kinetics code, which makes it suitable for the transient cases of both stochastic and intense neutron fields. Pulse withdrawal experiments and ramp feed experiments performed on the Transient Experiment Critical Facility (TRACY) are simulated with CriSAA. The transient characteristics of isolated and open criticality excursions on TRACY are studied. The simulation fits well with the experiments. Stochastic phenomena of the criticality excursions under a weak source case are studied. The statistics characteristics, including time and energy to first peak, power of first peak, and total energy, are shown. This work provides an advanced approach for criticality excursion evaluation and analysis.