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DOE OSTI · 22212730

Simulate-HEX - The multi-group diffusion equation in hexagonal-z geometry

Lindahl, S. O.
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Abstract

The multigroup diffusion equation is solved for the hexagonal-z geometry by dividing each hexagon into 6 triangles. In each triangle, the Fourier solution of the wave equation is approximated by 8 plane waves to describe the intra-nodal flux accurately. In the end an efficient Finite Difference like equation is obtained. The coefficients of this equation depend on the flux solution itself and they are updated once per power/void iteration. A numerical example demonstrates the high accuracy of the method. (authors)

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97 MATHEMATICS AND COMPUTINGACCURACYAPPROXIMATIONSDIFFUSION EQUATIONSGEOMETRYITERATIVE METHODSMATHEMATICAL SOLUTIONSMULTIGROUP THEORYWAVE EQUATIONS

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BibTeXRIS

Lindahl, S. O.. 2013-07-01. Simulate-HEX - The multi-group diffusion equation in hexagonal-z geometry. https://www.osti.gov/biblio/22212730

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