A nonoverlapping domain decomposition method for Legendre spectral collocation problems
Date
2007Source
Journal of Scientific ComputingVolume
32Issue
2Pages
373-409Google Scholar check
Keyword(s):
Metadata
Show full item recordAbstract
We consider the Dirichlet boundary value problem for Poisson's equation in an L-shaped region or a rectangle with a cross-point. In both cases, we approximate the Dirichlet problem using Legendre spectral collocation, that is, polynomial collocation at the Legendre-Gauss nodes. The L-shaped region is partitioned into three nonoverlapping rectangular subregions with two interfaces and the rectangle with the cross-point is partitioned into four rectangular subregions with four interfaces. In each rectangular subregion, the approximate solution is a polynomial tensor product that satisfies Poisson's equation at the collocation points. The approximate solution is continuous on the entire domain and its normal derivatives are continuous at the collocation points on the interfaces, but continuity of the normal derivatives across the interfaces is not guaranteed. At the cross point, we require continuity of the normal derivative in the vertical direction. The solution of the collocation problem is first reduced to finding the approximate solution on the interfaces. The discrete Steklov-Poincaré operator corresponding to the interfaces is self-adjoint and positive definite with respect to the discrete inner product associated with the collocation points on the interfaces. The approximate solution on the interfaces is computed using the preconditioned conjugate gradient method. A preconditioner is obtained from the discrete Steklov-Poincaré operators corresponding to pairs of the adjacent rectangular subregions. Once the solution of the discrete Steklov- Poincaré equation is obtained, the collocation solution in each rectangular subregion is computed using a matrix decomposition method. The total cost of the algorithm is O(N 3), where the number of unknowns is proportional to N 2. © 2007 Springer Science+Business Media, LLC.
Collections
Cite as
Related items
Showing items related by title, author, creator and subject.
-
Article
The MFS for the Cauchy problem in two-dimensional steady-state linear thermoelasticity
Marin, L.; Karageorghis, Andreas (2013)We study the reconstruction of the missing thermal and mechanical fields on an inaccessible part of the boundary for two-dimensional linear isotropic thermoelastic materials from over-prescribed noisy (Cauchy) data on the ...
-
Article
A numerical study of the SVDMFS solution of inverse boundary value problems in two-dimensional steady-state linear thermoelasticity
Marin, L.; Karageorghis, Andreas; Lesnic, D. (2015)We study the reconstruction of the missing thermal and mechanical data on an inaccessible part of the boundary in the case of two-dimensional linear isotropic thermoelastic materials from overprescribed noisy measurements ...
-
Article
The singular function boundary integral method for 3-D Laplacian problems with a boundary straight edge singularity
Christodoulou, Evgenia; Elliotis, Miltiades C.; Xenophontos, Christos A.; Georgiou, Georgios C. (2012)Three-dimensional Laplace problems with a boundary straight-edge singularity caused by two intersecting flat planes are considered. The solution in the neighbourhood of the straight edge can be expressed as an asymptotic ...