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DOE OSTI · 23203940

Uncertainty analysis for VERA problem 2 using the cell-code Condor v2.8.05

Ferraro, D.·Villarino, E.
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Abstract

Condor is a cell-level neutronic calculation code that applies multi-group collision probabilities with heterogeneous response coupling method within generic geometry configurations. Under the Condor's code continuous development, the incorporation of up-to-date methodologies and state-of-the-art practices in reactor analysis represents a driving force. In this work, the capabilities of Condor v2.8.05 to develop an uncertainty analysis for realistic PWR-kind fuel assemblies are studied. The Total Monte Carlo approach is applied to quantify the impact of fabrication tolerances in the code's results for reactivity and power distributions, by means of randomly sampled input values using the VERA problem 2 as basis. The VERA problem 2 proposes a series of Westinghouse 2D 17 x 17-type fuel lattices, to be calculated reflected at beginning-of-life without Xe. The configurations correspond to a modern PWR. Selected neutronic parameters from Condor runs are thus analyzed in terms of the observed spread as well as the obtained distributions for the randomly perturbed cases, showing the capability of the code to handle the required input data, as well as its ability to provide valuable insights regarding uncertainty quantification.

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21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTSBENCHMARKSC CODESCOMPUTERIZED SIMULATIONNEUTRON TRANSPORTPOWER DENSITYPWR TYPE REACTORSREACTIVITYVALIDATION

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Ferraro, D., Villarino, E.. 2022-07-01. Uncertainty analysis for VERA problem 2 using the cell-code Condor v2.8.05. https://doi.org/10.13182/physor22-37762

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