A Coarse Space Construction Based on Local DtN Maps

Frédéric Nataf (1) , Hua Xiang (1, 2) , Victorita Dolean (3, 4)

1 LJLL - Laboratoire Jacques-Louis Lions
2 School of Mathematics and Statistics [Wuhan]
3 NACHOS - Numerical modeling and high performance computing for evolution problems in complex domains and heterogeneous media
4 JAD - Laboratoire Jean Alexandre Dieudonné

Coarse grid correction is a key ingredient in order to have scalable domain decomposition methods. In this work we construct the coarse grid space using the low frequency modes of the subdomain DtN maps, and apply the obtained two-level preconditioner (the additive Schwarz method together with the new coarse grid) to the extended or the original linear system arising from an overlapping domain decomposition. The patch method is also added to further improve the convergence. Our method is suitable for the parallel implementation and its efficiency is demonstrated by numerical examples on problems with high heterogeneities for both manual and automatic partitionings.

Domaines: Analyse numérique [math.NA]

Frédéric Nataf, Hua Xiang, Victorita Dolean. A Coarse Space Construction Based on Local DtN Maps. 2010. ⟨hal-00491919v1⟩