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arXiv · 1301.0191

Adaptive-Multilevel BDDC and its parallel implementation

Bedřich Sousedík·Jakub Šístek·Jan Mandel
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Abstract

We combine the adaptive and multilevel approaches to the BDDC and formulate a method which allows an adaptive selection of constraints on each decomposition level. We also present a strategy for the solution of local eigenvalue problems in the adaptive algorithm using the LOBPCG method with a preconditioner based on standard components of the BDDC. The effectiveness of the method is illustrated on several engineering problems. It appears that the Adaptive-Multilevel BDDC algorithm is able to effectively detect troublesome parts on each decomposition level and improve convergence of the method. The developed open-source parallel implementation shows a good scalability as well as applicability to very large problems and core counts.

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Bedřich Sousedík, Jakub Šístek, Jan Mandel. 2013-01-02. Adaptive-Multilevel BDDC and its parallel implementation. https://doi.org/10.1007/s00607-013-0293-5

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