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DOE OSTI · 23203856

POLCA8 - modelling of cross section variations inside hexagonal assemblies

Lindahl, S. O.·Mylonakis, A.
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Abstract

This paper presents the POLCA8 approach for modelling non-constant cross section distributions inside hexagonal fuel assemblies. The multigroup diffusion equation is modified to account for intranodal cross section variations. The obtained equation is solved in a node-wise manner based on the Fourier expansion method. As a result of varying cross sections, the solution includes a particular part additionally to the homogeneous one. A method for obtaining the particular solution is derived. Numerical tests on a VVER-1000 core are presented showing the impact of cross-section variations to some key parameters for reactor operation. (authors)

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22 GENERAL STUDIES OF NUCLEAR REACTORSFUEL ASSEMBLIESGROUP CONSTANTSHEXAGONAL CONFIGURATIONHOMOGENIZATION METHODSMULTIGROUP THEORYNEUTRON DIFFUSION EQUATION

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Lindahl, S. O., Mylonakis, A.. 2022-07-01. POLCA8 - modelling of cross section variations inside hexagonal assemblies. https://doi.org/10.13182/physor22-37845

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