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2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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OECD NEA meeting focuses on irradiation experiments
Members of the OECD Nuclear Energy Agency’s Second Framework for Irradiation Experiments (FIDES-II) joint undertaking gathered from September 29 to October 3 in Ketchum, Idaho, for the technical advisory group and governing board meetings hosted by Idaho National Laboratory. The FIDES-II Framework aims to ensure and foster competences in experimental nuclear fuel and structural materials in-reactor experiments through a diverse set of Joint Experimental Programs (JEEPs).
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.