Parallel subdomain-based preconditioner for the schur complement

Abstract

We present a new parallelizable preconditioner that is used as the local component of a two-level preconditioner similar to BPS. On 2D model problems that exhibit either high anisotropy or discontinuity, we demonstrate its attractive numerical behaviour and compare it with the regular BPS. To alleviate the construction cost of this new preconditioner, that requires the computation of the local Schur complements, we propose a cheap alternative based on Incomplete Cholesky factorization, that reduces the computational cost but retains the good numerical features of the preconditioner. © Springer-Verlag Berlin Heidelberg 1999.