Substructuring preconditioners with novel interface solvers for general elliptic-type equations in three dimensions
For computational scientists solving large-scale 3D elliptic PDEs with discontinuous coefficients, this work offers cheap and easy-to-implement preconditioners that combine advantages of overlapping and non-overlapping domain decomposition methods.
This paper proposes two substructuring preconditioners for 3D elliptic-type equations with strongly discontinuous coefficients, achieving nearly optimal convergence rates and robustness to coefficient jumps in numerical tests on linear elasticity and Maxwell's equations.
In this paper we propose two variants of the substructuring preconditioner for solving three-dimensional elliptic-type equations with strongly discontinuous coefficients. In the new preconditioners, we use the simplest coarse solver associated with the finite element space induced by the coarse partition, and construct novel interface solvers based on some new observations. The resulting preconditioners share the merits of the non-overlapping domain decomposition method (DDM) and the overlapping DDM in the sense that they not only are cheap but also are easy to implement. We apply the proposed preconditioners to solve the linear elasticity problems and Maxwell's equations in three dimensions. Numerical results show that the convergence rate of PCG method with the preconditioners are nearly optimal, and also robust with respect to the (possibly large) jumps of the coefficients in the considered equations.