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DOE OSTI · 22212911

Efficient solutions to the NDA-NCA low-order eigenvalue problem

Willert, J. A.·Kelley, C. T.
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Abstract

Recent algorithmic advances combine moment-based acceleration and Jacobian-Free Newton-Krylov (JFNK) methods to accelerate the computation of the dominant eigenvalue in a k-eigenvalue calculation. In particular, NDA-NCA [1], builds a sequence of low-order (LO) diffusion-based eigenvalue problems in which the solution converges to the true eigenvalue solution. Within NDA-NCA, the solution to the LO k-eigenvalue problem is computed by solving a system of nonlinear equation using some variant of Newton's method. We show that we can speed up the solution to the LO problem dramatically by abandoning the JFNK method and exploiting the structure of the Jacobian matrix. (authors)

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97 MATHEMATICS AND COMPUTINGACCELERATIONEIGENFUNCTIONSEIGENVALUESEQUATIONSMATHEMATICAL SOLUTIONSMATRICESNEWTON METHODNONLINEAR PROBLEMSVELOCITY

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BibTeXRIS

Willert, J. A., Kelley, C. T.. 2013-07-01. Efficient solutions to the NDA-NCA low-order eigenvalue problem. https://www.osti.gov/biblio/22212911

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